REPRODUCTIVE CHARACTERISTICS OF THE MISSISSIPPI WHITE-TAILED. DEER WITH NOTES ON HISTORY, WEIGHTS AND. AGE-CLASS COMPOSITION Thesis for the Degree of Phi D. MICHIGAN STATE UNIVERSITY ROBERT E. NOBLE 1969 III 311293301090 5663 III IIIIIIIIII III I If ; ‘ i This is to certify that the thesis entitled REPRODUCTIVE CHARACTERISTICS OF THE MISSISSIPPI WHITE—TAILED DEER WITH NOTES ON HISTORY, WEIGHTS AND AGE-CLASS COMPOSITION presented by Robert E. Noble has been accepted towards fulfillment of the requirements for JILL degree in Major professor 0-169. moms Iv “DAB I SUNS' BUDV BINDERY INC. ‘ L “W BINDERS - "mum“ ABSTRACT REPRODUCTIVE CHARACTERISTICS OF THE MISSISSIPPI WHITE-TAILED DEER WITH NOTES ON HISTORY, WEIGHTS AND AGE-CLASS COMPOSITION BY Robert E. Nbble Over the three year period, February, 1960 through March, 1963, 354 female white-tailed deer were autopsied to determine their reproductive characteristics. Of these, 89 carried visible embryos. As determined from back-dated embryos, the mean breeding date for 50 does from north Mississippi was December 23 (standard deviation 13 days). The average breeding date for 26 does in south Mississippi was January 15 (standard deviation 19 days). Correspondingly the average fawning date in north Mississippi was July 13 (standard deviation 13 days) while the mean fawning date in south Mississippi was August 5 (standard deviation 19 days). The sample size of young does (1.5 years old) and old does (6.5 years and older) was small but there was no evidence that those collected had bred either earlier or later than other age-classes. Ovaries from 36 fawns col- lected from Nbvember through April were quiescent, showing Robert E. Noble neither corpora lutea nor well-developed graafian follicles. No breeding was observed in fawns (six-month-age-class). Based on examinations of 222 pairs of ovaries from deer collected Nevember 11 through January 9 in the Missis- sippi River bottomlands of Bolivar and Washington Counties, adult does there experience their first seasonal estrus about December 1. There was no significant difference between the average number of fetuses per gravid doe for deer from the highly-fertile batture forest (1.39) and for deer from the infertile longleaf pine belt (1.35). Collections from both areas were made on overstocked deer ranges indicating that excessive population density is more important than soil type in influencing reproductive rates in deer. The average number of fetuses per pregnant doe was 1.42, indicating that some areas had a higher reproductive rate than either of the overstocked ranges. 83 adult does were collected in late spring when breeding does are normally carrying visible fetuses. 76 were carrying young, a frequency of pregnancy of 91.6%. 78 pregnant does collected statewide were carrying 110 fetuses, and the ovaries of these deer contained 123 corpora lutea thus displaying an ovulation incidence of 1.58 and a repro- duction efficiency of 89.4%. Robert E. Noble Of 86 fetuses old enough to sex, 47 were males and 39 females (55:45). There was no significant difference be- tween the F-R or C—R measurement between twins in 37 sets of twins, except in a case where one was dead. Neither of opposite-sex twins tended to dominate in length. Only the one case of prenatal mortality was observed in 89 visibly pregnant does. The average age of 85 does 1.5 years and older was 4.58 years in a bottomland area that had been rigidly pro- tected from hunting for 33 years prior to scientific col- lecting. The average age of 22 does 1.5 years and older was 4.59 years in the infertile longleaf pine belt where does had been protected for 18 years. The 15 extra years of pro- tection at the delta location had added nothing to the aver- age age of deer on that range. Evidently, the maximum aver— age age of adult does in Mississippi herds is reached after the herd has been protected 10 years. Over 77% of 308 does collected in the state were less than 5.5 years old. Despite about identical reproductive rates and aver— age longevities for does from the two areas the does from the very fertile batture forest outweighed those from the infertile longleaf pine belt by an average of over 25 pounds per animal. REPRODUCTIVE CHARACTERISTICS OF THE MISSISSIPPI WHITE-TAILED DEER WITH NOTES ON HISTORY, WEIGHTS AND AGE-CLASS COMPOSITION BY Robert E. Nbble A THESIS Submitted to . Michigan State University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Department of Fisheries and Wildlife 1969 V‘s ACKNOWLEDGMENTS This study was financed by the Mississippi Game and Fish Commission as an approved Pittman-Robertson, Federal Aid in Wildlife Restoration Project. I wish to express my appreciation to my major pro- fessor, Dr. George A. Petrides, Department of Fisheries and Wildlife for reading and criticizing the manuscript and for his technical assistance and many helpful suggestions. Dr. Peter I. Tack of the Fisheries and Wildlife De- partment, Dr. Rollin H. Baker, Director of the University Museum and Dr. William D. Collins of the Physiology Depart- ment edited the final manuscript. I am grateful to Mississippi Game and Fish Commission employees, Mr. John H. Phares and Mr. William H. Turcotte, Federal Aid Coordinator and Chief of Game respectively, for making this study possible and coordinating the field work and for their patience, encouragement, suggestions and as- sistance in conducting the research. My sincere thanks to the following employees of the Mississippi Game and Fish Commission without whose help this work would have been impossible: Biologists Sterling G. Clawson* and Louis W. Bays, Warden J. Lester Jones, and Area Manager John Shirley for assistance in collecting deer; ii Biologists Ernest Parks and Pete Heard for invaluable as- sistance with lab work; Area Managers Quinton Breland,* Wilbur C. Carr, Edward H. Givens, Gerald Mize, Austin C. Shattles, John Starkey and Tate White for their genuine interest and complete cooperation while I worked on their respective game management areas. The Wardens of the Mississippi Game and Fish Com- mission have been particularly helpful with field work. My thanks to Wardens Bill Strong, J. Vaughn, L.Q. Daniels, NOrman Ammons, Matt E. Dakin, Wilton Brown, I.C. Farmer and Salvo A. Piazzo. Other personnel of the Commission to whom I am indebted are Fred Breland, Leaf River Game Management Area; Rabb Rodgers, Sardis Refuge; B.E. Gandy, Museum Di- rector; and John J. Jackson,* Choctaw County Game Area. I am most appreciative to the Board of Directors, Presidents, other officials and members of the Catfish Point, Delta Pine, Huntington Point, Merigold and Dixon Dossett Hunting Clubs of Bolivar County; the Ashbrook Island Hunting Club, Washington County; the Yucatan Island Hunting Club, Claiborne County; and the Coles Creek and Cypress Grove Hunt- ing Clubs, Jefferson County, who not only granted me per- mission to collect deer from their lands but assisted ma- terially in field work. Messrs. R.J. Landers, Henry Hiter, John Greer, Jr. and L.L. Vance permitted me the use of their respective camps while I worked in Bolivar County. On Ashbrook Island iii I stayed in the camp of Mr. P.B. Griffin. ”Mr. Richard Parker was kind enough to allow me the use of his hunting lodge near Yucatan Island. Throughout the course of this study I have spent many enjoyable evenings in the home of Mr. and Mrs. G.O. McDaniel, Boyle, Mississippi. Lastly, my sincere appreciation to my mother, Mrs. R.L. Noble and to my wife, Allene. They spent many hours assisting me with the analysis of data. *Deceased. iv TABLE OF CONTENTS INTRODUCTION . . OtTnI d. e Purpose of the Study . . . . . . Importance of the Study . . . History of Deer in Mississippi . . . . Present Range Regulations and Hunting Methods Pregnancy and Fetal Development RESEARCH METHODS AND MATERIALS a. b. C. Field Procedure . . . . . . . . . . . . . . Laboratory Procedure . . . . . . . . . . . . . Estimating Fetal Age . . . . . . The Study Areas . . . . Location of Specimen Collections in the Batture Forest . . ... . . . . . . . . Longleaf Pine Belt . . . . . . . . Miscellaneous Collecting Sites Range Conditions on the Collecting Areas BREEDING SEASON FOR MISSISSIPPI DOES a. b. 040 Definition of Breeding Season . . . . . . . Regions for Which Breeding Dates were Determined . . . . . . . . . . . . Northcentral Area . . . . . . . NOrthwestern Area Eastcentral Area . . . . . . . . . . . Southwestern Area . . . . . . . . Southern Area . . . . . . . . . . Breeding Dates in Nbrth Mississippi Breeding Dates in South Mississippi . . . . . Comparison of North and South Mississippi Breeding Dates . . . . . . . . . . . . Regional Differences in Breeding Dates Within Other States . . . . . . . . . . . Page I-‘mmNNH l-‘ 18 18 19 20 21 26 27 27 28 28 29 29 32 32 33 33 33 36 37 37 THE DATE OF SEASONAL ESTRUS IN BOLIVAR COUNTY DEER BREEDING BY FAWNS . . . . . . . . . . . a. Mississippi Fawns . . . . . . . . . . b. Incidence of Fawn Breeding in Other States . MISSISSIPPI FAWNING DATES . . . . . . . . . . . . . a. Fawning Dates in North Mississippi . . . . . b. Fawning Dates in South Mississippi . . c. Comparison of Mississippi Fawning Dates with Those in Other States . . MINIMUM AND MAXIMUM BREEDING AGES OF MISSISSIPPI DOES .. . . . .. . . . . .. . . . . .. . . . a. Age of Doe as Related to Date of Breeding BIRTH RATES IN MISSISSIPPI DOES . . . . . . . . . a Factors Influencing Birth Rates in Deer b. Average Number of Fetuses per Doe . . . . Statewide Sample . . . Fawn Production on Mississippi River Bottomlands as Compared with the Long- leaf Pine Belt . . . . . . Birth Rates as Related to Range Conditions . . . . . . . . . . . . . c. Frequency of Pregnancy . . . . . . . . . . Statewide . . . . . . . . . Mississippi River Bottomlands . . . . Longleaf Pine Belt . . . . . . . . . . Upland Hardwood Forest . . . . . . . d. Ovulation Incidence . . . Factors Influencing the Ovulation Incidence . . . . . Ovulation Incidence in Mississippi Deer e. Reproductive Efficiency . . . . Statewide Reproductive Efficiency f. Number of Fawns Following Gravid Does and the Number of Fetuses in utero . . . . . . 9. Age of Doe as Related to Number of Fetuses h. Functioning of the Right and Left Ovary vi. Page 46 52 52 52 56 56 57 58 62 64 65 65 66 67 67 70 71 71 72 72 72 74 74 75 76 78 78 80 82 FETAL SEX RATIO . . Uterine Sex Ratio in North Mississippi com- pared with South Mississippi . . . . b. Sex Ratio in Twins and Singles . . . . . c. Fetal Sex Ratio as Influenced by Range Condition . . . . . . . . d. Uterine Sex Ratios Reported in Other States PRENATAL MORTALITY . . . . . . . . . . . . . . . . . . 3. Length Comparison Between Twin Fetuses AGES OF DOES FROM PROTECTED HERDS . . . . . . . . . . a. Collections on Club Lands . . . . . . . . . . Marigold Hunting Club . . . . . . . . Catfish Point Hunting Club . . . . Huntington Point Hunting Club . Ashbrook Island Hunting Club . . . . . . . b. Collections in the Longleaf Pine Belt . . . . c. Comparison of Individual Herds . . d. Average Age in Statewide Sample . . . . . . WEIGHTS OF MISSISSIPPI DOES . . . . . . . . . . . a. Factors Influencing Weight . b. Doe Weights from the Batture Forest c. Doe Weights from the Longleaf Pine Belt d. Weights by Age Class . . . . . . . . . DEER MANAGEMENT IMPLICATIONS QIICYm (D Understanding the Mississippi Deer Herd The Time of Year to Hunt Antlerless Deer How to Facilitate the Harvest of Bucks Recommended Hunting Seasons for Adequately Stocked and Understocked Deer Ranges . Need for the Enforcement of Laws Against Free- Ranging Dogs . . . No Shortage of Breeding Bucks on Well- Stocked Ranges . . . . . . . . . . . . . . . APPENDIX HUNTING METHODS LITERATURE CITED vii Page 86 86 86 89 9O 92 94 98 98 99 101 102 102 103 103 104 108 109 109 112 112 117 117 119 121 122 122 123 124 126 Table 10. 11. LIST OF TABLES Estimated breeding periods for 76 gravid deer collected in Mississippi-—1960, 1961, 1962 . . . . . . . . . . . . . . . . . . . Climatological data for Mississippi deer collecting sites . . . . . . . . . . . Reported breeding dates for the genus _Qdocoileus in 28 states . . . . . . . The number of adult does, collected on antlerless hunts, by date and the number showing corpora lutea; Bolivar and Washing- ton Counties, 1960-1962 . . . . . . . Estimated fawning period (from back-dated embryos) for 76 gravid does collected in Mississippi, 1960, 1961, 1962 . . . . . Average number of fetuses per gravid doe as reported from various states and provinces Frequency of pregnancy in deer as reported from various states . . . . . . . . . Ovulation incidence in the genus Odocoileus as reported by various authorities . . Age of doe as related to number and sex of fetuses. Data from 89 gravid deer col- lected in Mississippi, 1960-1962 Uterine sex ratios in deer as reported for various states and provinces Length comparison between fetuses in 36 sets of twin deer collected in Mississippi, 1960-1962 . . . . viii Page 35 38 43 48 60 68 73 77 81 91 95 Table 12. 13. 14. 15. 16. 17. 18. Average ages of adult female deer (1.5 years old and older) collected from five Mississippi herds, 1960-1962 . . . Age—class distribution of 308 adult female deer collected in Mississippi, 1960-1962 Age classes of adult female deer from vari- ous herds in Mississippi Statistics by region on the live weights of Mississippi does 1.5 years of age and older . . . . . . . . . . . . . . . Live weights by age-class of female deer collected in Bolivar County, Mississippi, in January, February, March and April, 1960-1962 . . . . . . . . . . . Live weights by age-class of female deer collected in Bolivar and Washington Counties, Mississippi, in November and December, 1960-1962 Live weights, by age-class, of female deer collected in the longleaf pine belt of Mississippi in February and March, 1960- 1962 . . . . . . . ix Page 100 106 107 111 113 114 115 Figure LIST OF FIGURES Distribution of deer in Mississippi in 1929 (Leopold, 1929) . . . . . . . . Distribution of deer in Mississippi in 1967 Reproductive tract of a 6.5 year non-gravid doe. The ovaries of this deer did not contain corpora lutea but old rupture sites are plainly visible on the right ovary. COpiah Wildlife Management Area Laboratory, Barlow, Mississippi, May 3, 1963. Photo- graph by W. H. Turcotte and the author Ovaries from a 2.5-year-old pregnant doe showing (sectioned) a well-formed corpus luteum. The right ovary is intact. The ruler is graduated in inches. Copiah Wild- life Management Area Laboratory, Barlow, Mississippi, May 3, 1963. Photograph by W. H. Turcotte and the author . . . . . . A series of seven white-tailed deer fetuses showing progressive stages of development. The estimated age of each fetus from small to large is: 19, 28, 34, 38, 60 and 68 days. Copiah Wildlife Management Area Laboratory, Barlow, Mississippi, May 3, 1963. Photograph by W. H. Turcotte and the author . . . . . . . . . . . . . . . The author assisted by Biologist L. P. Heard (standing) measuring a deer embryo at the Copiah Wildlife Management Area Laboratory, Barlow, Mississippi, May 3, 1963. Photo- graph by W. H. Turcotte . . . . . . . Page 10 12 14 15 22 Figure Page 7. A white-tailed deer embryo about 38 days after conception. The ruler is gradu- ated in millimeters. Copiah Wildlife Management Area Laboratory, Barlow, Mississippi, May 3,1963 Photograph by W. H Turcotte and the author . . . - 23 8. Deer collecting sites and approximate geo— graphical boundaries of North and South Mississippi . . . . . . . . . . . . . . . - 25 9. Mean deer breeding dates for five areas in Mississippi . . . . . . . . . . . . . . . . 31 10. Deer breeding dates by regions, Mississippi, 1960-1962 0 o o o o o o o o . e o o o o . 0 42 ll. Immature reproductive tract from a six—month- old female fawn collected March 14, 1962, in Bolivar County, Mississippi. This animal was typical of all female fawns collected in this study. The smooth, white, relatively flat, quiescent ovaries are visible. Copiah Wildlife Management Area Laboratory, Barlow, Mississippi, May 3, 1963. Photograph by W. H. Turcotte and the author . . . . . . . . . . . . . . . 55 12. Reproductive tract of a 1.5-year-old doe con- taining a single fetus. COpiah Wildlife Management Area Laboratory, Barlow, Missis- sippi, May 3,1963. Photograph by W. H Turcotte and the author . . . . . . . . 61 13. A single white-tailed deer embryo. The right ovary contained a well—developed corpus luteum. The left ovary did not produce an ovum. COpiah Wildlife Management Area Laboratory, Barlow, Mississippi, May 3, 1963 Photograph by W. H. Turcotte and the author . . . . . . . . . . . . . . . 84 14. A white—tailed deer embryo about 28 days old. COpiah Wildlife Management Area Laboratory, Barlow, Mississippi, May 3, 1963. Photograph by W. H Turcotte and the author . . . . . . . . . . . . . . 85 xi Figure 15. 16. 17. 18. Twin fetuses lg utero about 88 days after cenception. The external genital organs are plainly visible. The fetus on the left is a female. The one on the right is a male. Copiah Wildlife Management Area Laboratory, Barlow, Mississippi, May 3,1963. Photograph by W. H. Turcotte and the author . . . . . . . A white-tailed deer fetus about 140 days old. The black spot on the head is the potential site of the right antler, but these spots are found on both male and female fetuses. Copiah Wildlife Management Area Laboratory, Barlow, Mississippi, May 3, 1963. Photo- graph by W. H. Turcotte and the author These two fetuses were taken from a 7.5- year—old doe killed March 5, 1962. The top fetus was apparently alive and healthy up until the time of the doe's death. The second fetus probably died when about 39 days old and had been dead in utero about 26 days. Copiah Wildlife Management Area Laboratory, Barlow, Mississippi, May 3, 1963 Photograph by. W. H. Turcotte and the author . . . . . . . . . Pregnant reproductive tract of a 2.5-year- old doe (containing twins) about 78 days after conception. The ruler is 150 mm long. Copiah Wildlife Management Area , Laboratory, Barlow, Mississippi, May 3,‘L 1963 Photograph .by W. H. Turcotte and the author . . . . . . . . . . . . xii Page 87 88 96 97 INTRODUCTION The white-tailed deer (Odocoileus virginianus) is the only big game animal in Mississippi present in sufficient numbers to justify hunting. In early times the black bear (Ursus americanus) was found over a large portion of the II state, but today it is totally protected and there are probably less than 50 remaining in the state. Unlike the bear, the deer in recent years has benefited from man's ef- fects upon its environment. As a consequence, there are per- haps more deer in Mississippi today than there were at the time of white man's first arrival. a. Purpose of the Study This study was conducted for the Mississippi Game and Fish Commission as Pittman-Robertson Federal Aid in Wild- life Restoration, Project Number W‘48-R-8, Job No. 1, en- titled, "A Study of Reproduction and Productivity in Mississippi Deer Herdsl' The purpose of the study were to: 1. Determine dates of mating and fawning. 2. Establish the date of first estrus. 3. Gather information on prenatal sex ratios, pre- natal mortality, and fecundity. 4. Determine the extent of breeding by first year does. 5. Investigate the age distribution of female deer in herds where does have been rigidly protected for many years. 6. Compare the productivity of does on the highly fertile soils of the batture forest with those of the relatively infertile longleaf pine belt. 7. Investigate the popular opinion that "old" does do not breed. b. Importance of the Study Until this study, no organized research had been con- ducted on deer in Mississippi. All management was based on research findings in other states, largely states hundreds of miles from Mississippi (e.g., New York and Michigan) and representing different ecological conditions. In contrast to conditions in northern states, Mississippi deer do not congregate in winter and hunting is largely with the aid of dogs. Comparatively speaking, Mississippi winter weather is mild and especially so in the more southern regions of the state. Only a few other states have conditions similar to the batture forest, and very little research has been con- ducted on the deer herds inhabiting this heavily forested, highly fertile region adjacent to the Mississippi River. c. History of Deer in Mississippi The white-tailed deer and its ancestors have lived through drastic changes. Deer have been in North America about 20 million years. In primitive times the whitetail undoubtedly ranged over all of Mississippi. The state was colonized by the French in 1699 (McLemore and McLemore, 1959) and probably these early settlers found no deer population such as we know today. As indicated by several septuagen- arians who remembered hunting in the virgin longleaf pine (Pinus palustris)* belt of southern Mississippi, the virgin forests could not have supported high deer concentrations. They recalled the invariably open and clean conditions of the forest floor and their ability to see for long distances through the timber stand. Similar conditions existed in the virgin hardwood forest. In 1905, Mississippi's first deer hunting season was set by the Legislature to extend from September 15 through March 1. In 1910, an act was passed imposing the state's first bag limit: five deer per year with fawns illegal. By 1915, the Legislature had retained the five deer limit but declared only males to be legal game. In 1928, the Legis- lature reduced the hunting season to November 15 through February 15 and the bag limit to three males. DeSpite these early attempts at protection, deer had been exterminated over most of the state by 1925. A few small herds remained in inaccessible portions of the Mississippi River flood plain (loosely called the "Delta") and in the Pearl and Pascagoula River swamps (Figure l). Fortunately for the deer, intensive logging and indiscriminate *Botanical nomenclature after Brown (1945) except where otherwise noted. Figure 1. Distribution of deer in Mississippi in 1929. (Leopold, 1929). L “- I ‘Q m White-tail deer range x 0 Isolated seed stock Recent planting (outcome uncertain) Possible occurrence - unable to verify timber cutting occurred between 1900 and 1925, removing most of the virgin forest in Mississippi. During this time, due to unregulated hunting pressure, the deer population of the state reached an all-time low. Leopold (1929) estimated the entire deer population of the state in 1929 at no more than a few hundred animals and advised that . with the possible exception of very limited parts of the Delta, deer can nowhere be said to persist in numbers justifying hunting. The "cut-out-and-get-out” policy of early logging operations was followed in many instances by wild fires that burned thousands of acres, removed the residual timber stand, and exposed the forest floor to sunlight. These conditions resulted in ideal second-growth timber favorable to deer. The Mississippi Game and Fish Commission was organ- ized June 16, 1932. Thereafter, deer were given at least partial protection. The Commission's first game survey in 1933 revealed that there might be a few hundred deer scattered over 34 of the 82 counties of the state (Handley, 1952). To supplement these, between 1933 and 1940 approximately 400 deer were purchased by the Mississippi Game and Fish Com- mission (Fleming, 1953), largely from North Carolina, Texas and Mexico (Handley, 1952). By 1940, Mississippi was oper- ating 40 refuges totaling 241,138 acres, and the state claimed a deer population of 4,600 (Handley, undated). From 1943 through 1958, the Mississippi Game and Fish Commission trapped 963 deer from these refuges and released them at favorable locations over the state (Anonymous, 1958). From a low of a few hundred deer in 1933, the popu- lation increased to 4,600 by 1940. By 1943, the population had grown to an estimated 10,000, and during that year hunters bagged 450 bucks in the 26 open counties (Anonymous, 1958). In 1947, the deer herd was estimated at 20,000; 12,000 hunters killed 1,500 bucks during a short open season then. By 1948 the deer herd had increased to 25,000, and 20,000 hunters killed 1,750 bucks during a 15 day open season. Deer continued to expand so that by 1961 there was an estimated 120,000 deer in the state. During the 1961-1962 hunting seasons about 80,000 hunters harvested 11,015 deer. The 1964 estimate placed the deer population at approximately 180,000, and during the 1963—1964 seasons about 90,000 hunters bagged 18,143 deer. In 1966, the Mississippi deer herd was estimated at 240,000. During the 1966—1967 seasons 23,431 deer were legally taken in the state. 31,578 deer were legally killed and reported in 1967-1968. The Mississippi Game and Fish Commission deserves considerable credit for its deer management program over the last 30 years, but the value of widespread indiscriminate logging should not be overlooked as a factor creating a favorable vegetative habitat. The Game and Fish Commission was established shortly after the removal of the virgin forest. The young second growth timber offered ideal deer habitat. The protection and restocking program of the Mississippi Game and Fish Commission arrived on the scene at a favorable time. Present Range 1 Deer are now present in every county of Mississippi (Figure 2). During the 1966-1967 gun seasons, 79 of the 82 counties of the state were either completely, or partly Open to deer hunting. Mississippi's deer population has increased markedly over the last 25 years, but many counties, due to inadequate management, still do not have the deer they are capable of supporting. Of the 1967-1968 kill, 17,517 (55vq%) were killed in 10 counties which represent less than 15 per- cent of the total land area of the state. The highest concentrations of deer occurred in the batture forest adjacent to the Mississippi River. d. Regulations and Hunting Methods Traditionally, the annual deer season in Mississippi Opens on November 20 and extends through December 1. The season is then closed for 25 days and opens again on December 26, in most counties extending through January 9. Sportsmen in some counties, however, insist that their second season extend no longer than a week. Therefore, in Bolivar, washington, and a few other north-delta counties the second season closes on January 3. Figure 2. Distribution of deer in Mississippi in 1967. 10 3%} 2250‘ LEGEND mm High Density [:I Medium Density I Low De ns 1 t y ”73:77.. 2'. vii}? L_.__.___1 Low to none 11 The method of hunting varies over the state. In the north—central hill section, dogs and high—powered rifles are prohibited. In the north-delta (northwestern) section hunters use both dogs and high-powered rifles. In the south- delta (southwestern), rifles are largely prohibited because many hunters follow their hounds on horseback. In the long- leaf pine belt (southeastern and extreme south), shotguns are used more commonly than rifles. In some parts of this last area, deer are hunted with dogs. In other parts, dogs are prohibited. The bag limit from about 1935 until 1957 was one buck per hunter per year. In 1957, the bag was increased to two bucks, one per season segment. In most counties of Mississippi, however, the deer bag limit is traditionally ignored and, due to lack of cooperation from local people, wardens are helpless to enforce the law. In most counties antlerless deer, nevertheless, are well protected. To kill a doe even by mistake forfeits one's membership in most hunting clubs. Although bucks are heavily harvested in some areas, deer herds remain mostly on the in- crease because of the many females present in the herds. Several areas have become seriously overpopulated. e. Pregnancy and Fetal DevelOpment In white-tailed deer the external appearance of the uterus does not change appreciably until after about 20 days Figure 3. Reproductive tract of a 6.5 year non-gravid doe. The ovaries of this deer did not contain corpora lutea but old rupture sites are plainly visible on the right ovary. Copiah Wildlife Management Area Laboratory, Barlow, Mississippi, May 3, 1963. Photograph by W. H. Turcotte and the author. 12 L .1 J‘..Uh{1 OU>IHIUIR the...» ... _ =z.>. . 13 of gestation, hence early evidence of pregnancy must be sought by examination of the ovaries (Cheatum and Morton, 1946). If the female has passed through "heat" (and, there- fore, has possibly bred successfully), gross examination would reveal corpora lutea. It is not known how long is required for an embryo to become visible to the naked eye. One of the smaller known-age embryos reported by Severinghaus and Cheatum (1956) measured 8 mm (crown-rump) at 28 days and another measured 16 mm at 37 days. Hudson and Bowman (1959) reported that a known—age mule deer embryo measured 6.6 mm at 28 days and another was 32.4 mm at 48 days. Cheatum and Morton (1946) constructed a growth curve for white-tailed deer embryos and fetuses based on 15 known- age specimens. Hudson and Bowman (1959) constructed a growth curve for Rocky Mountain mule deer embryos using five known- age specimens. The two curves are almost identical. The gestation period in deer seems to have been satisfactorily determined. Haugen (1959) reported the ges- tation period of 12 white-tailed does under experimental con- ditions in Alabama. The average obtained by Haugen was 193.8 days with a minimum of 187 days and a maximum of 198 days. Golley (1957a) observed five Columbian black-tailed deer (ngcoileus hemionus columbianus) in Washington State and found that the gestation period averaged 203 days and ranged from 199 to 207 days. Severinghaus (in litt., 1960), Figure 4. Ovaries from a 2.5 year—old pregnant doe showing (sectioned) a well—formed corpus luteum. The right ovary is intact. The ruler is graduated in inches. Copiah Wildlife Management Area Laboratory, Barlow, Mississippi, May 3, 1963. Photograph by W. H. Turcotte and the author. Figure 5. A series of seven white-tailed deer fetuses show- ing progressive stages of development. The esti- mated age of each fetus from small to large is 19, 28, 34, 38,3{60 and 68 days. Copiah Wildlife Management Area Laboratory, Barlow, Mississippi, May 3, 1963. Photograph by W. H. Turcotte and the author. 15 I\.'\3_ I - H 4 CAROLINA BIOLOGICAL A F L (IIJlTIJNE'H ELON COLLEGE. N C. 16 reviewed all literature available to him and reported 202 days to be the average gestation period for the whitetail., RESEARCH METHODS AND MATERIALS Collecting for the study extended over the three— year period February 1960 through March 1962 and involved 354 female specimens. Of 117 deer taken in Spring (February, March and April) under special collecting permit, 24 were males which were mistakenly shot for females. Of the 117 deer collected under permit, 110 were taken by gun, 3 were killed by automobiles, 2 were killed by free-ranging dogs, and 2 were confiscated as illegal kills. 34 animals were shot nocturnally with the aid of headlights, and 76 were killed, mostly in late afternoon, on management area or refuge food plots. Seven hunting clubs in Washington and Bolivar Counties agreed to hold limited antlerless-deer hunts on their lands in 1960 and 1961. These were the first antlerless-deer seasons in the state. The dates of these hunts were set so that no two clubs hunted on the same day. This allowed me an opportunity to be on most hunts and to collect a maximum of information. The dates were also fixed to provide a sample of 261 female reproductive tracts from the first week in November through the first week in January. 17 18 .In summary, 93 females (76 pregnant adults, 7 non- gravid adults, and 10 nonpregnant fawns) were collected in spring, and 261 females were collected on antlerless hunts in washington and Bolivar Counties in December, 1960 and January, November and December, 1961. a. Field Procedure Animals were weighed in the field on Chatillan dis- placement scales. No allowances were made for blood losses although these may have amounted to a pound or two in some cases. _Reproductive tracts were removed_in_tgtg, labelled, and placed in 10% formalin. Both lower mandibles were col- lected and labelled. b. Laboratory Procedure ,Reproductive tracts and jawbones were examined at the Copiah County Wildlife Management Area Laboratory, Barlow, Mississippi. Embryos and fetuses were carefully re- moved from the uterus and ages in days were estimated ac- dording to methods described by Cheatum and Morton (1946). Ovaries were examined grossly for corpora lutea (Cheatum, 1949; Golley, 1957b). Jawbones were cleaned and ages were assigned by the method described by Severinghaus (1949a). Because of the difficulties in identification, no at- tempt was made to locate corpora albicantia. True corpora 19 lutea either of estrus or of pregnancy, however, are easily recognized. The possibility of error is small. (In the technique originally established by Cheatum (1949), corpora albicantia were identified on the basis of several as- sumptions. Golley (1957b), however, proved these as- sumptions to be largely incorrect and both Cheatum and Golley have pointed out that the procedure for gross examination of deer ovaries, which does not involve the more complicated histological techniques, is practical only when applied with a full knowledge of its limitations-) Estimating Fetal Age The ages of embryos and fetuses were estimated from total length. The crown-rump (C-R) measurement was taken on embryos and the forehead-rump (F-R) measurement on fetuses. C-R was measured from the mesencephalon to the posterior end of the specimen. The F—R measurement was taken from the points of the coronal and sagittal sutures of the skull to the tuberosity of the ischium. Embryos were measured with a Heliss caliper. Fetuses longer than 120 mm were measured with a ruler. Immediately after removal from the uterus but before measuring and weighing, fetuses and embryos were partially dried on filter paper. Weights were taken on an Ohaus Cent- o-gram Moder 311 analytical balance. 20 The average length was recorded for multiple-birth embryos and fetuses, since for 17 sets of opposite-sex twins Hudson (1956) found no significant tendency for either sex to dominate in weight or F-R length. In this paper, the term "fawn" refers to animals less than 10 months old. Most fawns collected were four to seven months of age. No specimens 10 through 13 months of age were taken. The term "adult" refers to an animal 14 months of age or older. No monozygotic or true twins were observed. For con- venience, "twin" is used throughout this paper to refer to two fetuses in the same reproductive tract. Each fetus seen was apparently the product of a separate ovum since two or more corpora lutea were found in the ovaries of every doe carrying two fetuses. In deer the embryonic stage covers about the first 66 days of pregnancy. After the external organs are formed, at about 66 to 70 days, the embryo becomes a fetus. The fetal stage comprises the last 4.5 to 5 months of pregnancy. c. The Study Areas 311 female deer were collected in the batture forest, 24 in the longleaf pine belt and 19 in the loblolly pine (Pinus taeda)-—shortleaf pine (Pinus echinata)--upland hard- wood type. 21 Location of Specimen Collections in the_§atture Forest The collection sites in Bolivar, Washington, Clai- borne, and Jefferson Counties (Figure 8) typified the batture forest, the heavily forested region between the main levee of the Mississippi River (or in Claiborne and Jefferson Counties the natural bluffs) and the river itself. The area is subject to annual inundation from flood waters of the Mississippi River. ,It contains very fertile alluvial de- posits, 35 feet deep in places (James, 1951). .The Mississippi River batture extends from Cairo, Illinois, to the Gulf of Mexico and contains about two million acres (McKnight, 1950). There are about 259,700 acres in the batture forest of Missississippi (Krinard,_in_ligt., 1962). The batture forest (Putnam, £3 31., 1960) overstory is characterized by sweetgum (Liguidambar styraciflua), cottonwood (ngulus deltoides), sycamore Platanus 2221* dentalis), pecan (Carya illinoensis), persimmon (Diospyros virginiana), hackberry (Celtis laevigata), black willow (Salix nigra), boxelder (Acer negundo), American elm (Ulnus americana), and several species of oaks (Quercus Spp.). Understory plants include giant cane (Arundinaria gigantea), Johnson grass (Sorgum halepense), cocklebur (Xanthium _pennsylvanicum), stinging nettle (Tragia urticifolia) poke- weed (Phytolacca americana), dewberries (Rubus spp.), grapes Vitis spp.), greenbriers (Smilax spp.), poison ivy (Rhus Figure 6. The author assisted by Biologist L. P. Heard (standing) measuring a deer embryo at the Copiah Wildlife Management Area Laboratory, Barlow, Mississippi, May 3, 1963. Photograph by W. H. Turcotte. 22 Figure 7. A white-tailed deer embryo about 38 days after conception. The ruler is graduated in milli- meters. Copiah Wildlife Management Area Laboratory, Barlow, Mississippi, May 3, 1963. Photograph by W. H. Turcotte and the author. _ ——‘— — _ _ __ — _— .— , I IIIIIIIIIIIIIIIIIIIIIIIIIIII IIIIIIIIII 3 4 5 6 Figure 8. :24 Deer collecting sites and approximate geographi- cal boundaries of North and South Mississippi. 25 . Denotes deer collecting site dy------4-- North Central South 26 radicans), buttonbush (Cephalanthus occidentalis), possumhaw (Ilex decidua), and swamp privet (Forestiera acuminata). Some areas of the batture forest support one deer per six acres (Noble, 1961a). Longleaf Pine Belt The longleaf pine belt is characterized by almost pure stands of longleaf pine. Thousands of acres of these pine stands are maintained in most instances by controlled burning and deadening of other tree species. These-are ac— cepted forestry practices used by state, private and federal foresters in the region. Deer collections in the longleaf pine belt were made in Jones, Stone, Perry, and Pearl River Counties. Lesser vegetation in the understory of the pine stands include flowering dogwood (Cornus florigg), tree- huckleberry (Vaccinium arboreum), gallberry (Ilex glabra), St. Andrew's cross (Ascyrum hypericoides), and winged sumac (Rhus copallium). The flood plains of small streams in this area sup- port sweetbay (Magnolia virginiana), titi (Cyrill§_racemi- _flgga), silverbell (Halesia diptera), bigleaf snowball (Styrax grandifolia), blue beech (Carpinus caroliniang), several species of oaks, beech (Fagus grandifolia), and magnolia (Magnolia grandiflora). .‘lillllll .I .[Illlu .‘II‘ 27 The soils of the longleaf pine belt are largely sandy and infertile. The maximum deer carrying capacity usually does not exceed one deer per 23 to 30 acres. ggscellaneous Collecting Sites The shortleaf—loblolly pine and the upland hardwood type were not heavily sampled in this study. They have been described by westveld (1949). 12 female specimens were collected in the loblolly- shortleaf forests of Copiah, Choctaw, and Noxubee Counties, and 7 were taken from the upland hardwood forest of Lafayette County. Range Conditions on the Collecting Areas Deer taken in Bolivar, Washington, Claiborne, Stone, and Perry Counties represent animals from overpopulated ranges. Lafayette, Jefferson, Pearl River, and Jones Counties are considered to be moderately and properly stocked. Copiah, Noxubee, and Choctaw Counties are under- stocked deer ranges. 311 of the female Specimens were taken from over- populated ranges, 24 females were collected from preperly stocked areas, and 9 does were taken from understocked districts. This investigation, therefore, is largely a study of breeding and productivity on overpopulated deer ranges in Mississippi. BREEDING SEASON FOR MISSISSIPPI DOES Sandusky (1960) summed up what was known about deer breeding dates in Mississippi when he wrote in his Sunday news column, "Outdoor Mississippi": Even arbitrary dates are lacking for the height of breeding and fawn drop, although it is known that our deer breed some time between November 1 and January 15 and that fawns are dropped some time be— tween May 1 and October 1. a. Definition of Breeding Season Cheatum and Morton (1946) defined the rutting season as the period when the buck is fertile. The male whitetail. however, is sexually active over a longer period of time than the female (Trippensee, 1948). A similar situation is found in other mammals (Layne, 1958; Vaughn, 1962). The breeding season is defined here as the period during which conception regularly occurs. This definition delimits the period regardless of sexual differences in either physiology or behavior. The conception dates for Mississippi deer studied here were determined by subtracting the age of each fetus found in the reproductive tracts of 89 pregnant does from the date of specimen collection. 28 29 b. Regions for Which Breeding Dates Were Determined Gravid deer were collected in five areas of Mississippi (Figure 9); seven were taken from the north- central portion of the state (Lafayette County), 49 were collected along the Mississippi River in the northwestern portion (Bolivar County), seven were taken from eastcentral Mississippi (Choctaw and Noxubee Counties), six were col- lected in southwestern Mississippi (Jefferson, Claiborne, and COpiah Counties), and 20 were taken from the extreme southern portions of the state (Jones, Perry, Pearl River, and Stone Counties). Breeding dates are given (Figure 9) for each of five state areas. Because of the relatively small number of specimens from some areas, however, detailed discussion is restricted to 63 gravid deer from north Mississippi and 26 from south Mississippi. Apparently, dates of breeding within the state are determined to some extent by latitude, presumably through adaptation to local environments. There is a noticeable difference in breeding dates between north and south Mississippi (see beyond). Northcentral Area The mean breeding date for seven pregnant does was December 22 with a standard deviation of eight days. The 30 Figure 9. Mean deer breeding dates for five areas in Mississippi. Number in parentheses is the number of gravid does in the sample. 31 Northcentral 0 December 22 S.D. = 8 days (7) _Northwestern December 19 S.D. = 9 days (36) _Eastcentral 0 January 12 (7) _Southwestern January 7 S.D. = 11.5 days (6) m January 20 S.D. = 21 days (20) 32 earliest breeding date was December 12 and the latest January 5, but only one animal had bred in January. All were col- lected in the upland hardwood forest of Lafayette County. Northwestern Area Deer from the northwestern portion of the state were collected in the batture forest of Bolivar County. The average breeding date for 36 gravid does there was December 19 with a standard deviation of 9 days. The earliest breed- ing date was December 5 and the latest January 18. 33 (91%) of these does had bred during December. There was no ap- preciable difference between breeding dates in northcentral Mississippi and northwestern Mississippi. Eastcentral Area The main breeding date for seven gravid does in east— central Mississippi was January 12 with a standard deviation of 13 days. The earliest date was December 28 and the latest February 3. Only one had bred in December. The does from this area had conceived about three weeks later than does from northcentral and northwestern Mississippi. Yet only about 95 miles separates the east- central collection sites from the collection sites in the northcentral and northwestern areas. The eastcentral sample was small, however, and the validity of these differences must await verification. The northcentral, northwestern, and 33 eastcentral areas have been combined to represent breeding dates in north Mississippi. Southwestern Area The six pregnant does collected in the southwestern area had bred between December 22 and January 22. The mean breeding date was January 7; the standard deviation being 11.5 days. Southern Area Deer from extreme southern Mississippi were collected in the longleaf pine belt. The average breeding date for 20 pregnant deer was January 20 with a standard deviation of 21 days. Breeding dates extended over the period December 13 to February 24. Breeding dates from the southwestern and southern areas were combined to represent breeding dates in south Mississippi. c. Breeding Dates in North Mississippi Deer mate several weeks earlier in northern Mississippi than they do in the southern part of the state. The average breeding date was determined for 50 pregnant does collected in north Mississippi in late spring when breeding does normally carry visible fetuses. The com- puted date was December 23, with a standard deviation of 13 days. Successful mating extended over a 61-day period, from December 5 through February 3. 40 (80.0%) of the sample had 34 bred during December; nine (18.0%) in January, and only one (2.0%) in February. In north Mississippi, the height of breeding occurred during the two—week period of December 5 through December 18, when 44.0% of the sample had bred (Table 1). Over 69.0% of the does in the region had bred be- tween the tWO hunting seasons (December 1 - 25), and 16.0% had bred after the second hunting season (after January 3). Only seven (14.0%) bred during the second hunting season (December 26 - January 3). Hale (1959) reported that dis- turbance by hunters in Wisconsin during the rut had little effect on the success of the breeding season. Nevertheless, he pointed out that in an area of heavy hunting pressure and low deer numbers, a season timed to hit the peak of the . breeding could be a method of intensifying population con- trol. The main effect of such management, however, would probably be a later fawn crop since does disturbed by hunters during their regular breeding period would experi— ence another estrus about 28 days later. Deer in most of north Mississippi, and especially in the batture forest, are hunted with dogs. This may be the reason that so little successful breeding occurred there during the hunting season. Seven (14.0%) of the 50 pregnant does collected in the late springs of 1960 and 1962 had bred between December 5 and December 11. Between January 3 and January 9, 1961, 35 .womuQEo ooumolxomn Eoum ooumawumo mcflums mo mange lemme «no em Sumsunom m mumsunom I ma HonEooon ma ma mumscmb I m monsooon ma mm monsooon swamm Ammmav oumn omcmm Ammmnv oumn coaumfl>oa mcwoooum cofiumfl>on mcfloooum oumocmum com: oumocmum cam: Hmmwmmammaz nusom Ammflmmflmmflz canoz o.ooa om o.ooa om Hmuoe v.5 N 0.0 o «m mumsunom I ma hnmsunom H.mm o o.m H NH mumsunom I om hnmscmb 0.HH m o.¢ N mm mumsCmb I ma ammscwb H.mm w o.vH n ma mumscmo I m mumscmh o.mm h 0.0m ma H wnmscmo I ma HonEoUon >.h N o.¢¢ mm ma HonEooon I m HoQEooon ucoouom quEsZ ucoouom Honssz ooanom mcfloooum moon Ammwmmwmmflz nusom moon Ammflmmflmmflz nunoz .Noma .Homa .ooma Ilflmmflmmflnmaz.cfl oouooaaoo Homo ofl>mum on How smoOHHom mcfloooun ooumeflumm .H magma 36 73 adult does were collected from this region. Only 13 (17.8%) carried visible fetuses, and eight of these (11% of the 73 collected) had bred between December 5 and December 11. These data indicate little if any difference between breeding dates for the three years concerned. Probably 11% to 14% of the breeding adult does in Bolivar County and per- haps throughout north Mississippi regularly conceive between December 5 and December 11. d. Breeding Dates in South Mississippi The mean breeding date for 26 gravid does from this region was January 15 with a standard deviation of 19 days. Breeding dates (Table 1) extended over a 74-day period from December 13 through February 24. Seven (26.9%) had bred in December, 12 (46.2%) had bred in January and seven (26.9%) had bred in February. The height of breeding occurred during the 28-day period between December 19 and January 15, when half of the animals bred. Three (11.5%) does bred between the hunting season: 10 (38.5%) mated during the second season (December 26 - January 9), and 13 (50.0%) became pregnant after the second hunting season. Since many deer bred during the second gun season, the hunting season evidently may not influence breed- ing in south Mississippi. Hunters were not permitted to use dogs on the areas where these deer were collected. 37 e. Comparison of North and South Mississippi Breeding Dates In north Mississippi, the height of successful breed— ing occurred about three weeks earlier than in the south (Table 1). Breeding in the north commenced eight days and ended 21 days sooner than breeding in the south. The differ- ence in breeding dates is correlated with latitude and cli- mate. The airline distance between extreme northern and southern collection sites was about 250 miles, while the closest collection sites were 87 miles apart. Proximity to the Gulf of Mexico is largely responsible fer south Mississippi's relatively mild climate. A marked difference in climate exists between the extreme collection sites of Lafayette County in the north and Stone County in the south. The December mean temperature in Lafayette and Stone Counties over a 29—year period (1931-1960) was 46.9OF. and 54.30F. respectively. Lafayette and Stone Counties over the 29-year period of 1921-1950 averaged 224 and 272 frost- free days a year, respectively. Other climatological data for the two regions (Table 2) show similar differences. f. Regional Differences in Breeding Dates Within Other States Reports of regional differences in breeding dates within a state are not uncommon. According to Sweet and Wright (undated), the peak of breeding activity among adult does in southern New Jersey is approximately 12 days later 38 .mcmwmwsoq .mcmoano 3oz .smonsm Honumo3 .ooHoEEoo mo unoEuummon .m .D can an ooow>oum mumo HmuamoHoumENHoe Acuonusom oEoHuxmv Hm.Hm m.>o N .oon NhN o.mm m.vm ocoum Acumauuozv Na.mm m.¢o m .>oz mNN m.oe N.m¢ comuomwob Hmmammammaz nusom Acnocusom oEoHuxmv em.mm m.mo 0H .>oz HMN m.m¢ H.5v Bouooco Acnonuuoz oEoHuxmv H~.mm A.me A .>oz emm e.oe e.me muuwmmmmq Hmmwmmwmmaz cuuoz AommHIHmmHV Aoomalammav AommHIHNmHV AoomHIHNmHV Ammmav Aoomalammav mmaocH mo umoum mama so no mmuwm cw Hammcamm CH .QEoB onwaaflx umufih. mosh umouh CH .QEoB CH .mEoB cowuooaaoo amused ommno>¢ amused one: no oumn cam: .02 new: .02 cmoz 9 Own— GMT: J'l IIII IIII IIIII s.moufim meauooaaoo Hoop Ammammflmmflz How sumo Hmowmoaoumeflao .N magma 39 than among adult does in the northern part of the state. Calhoun (in_litt., 1962) reported that does in northern Illinois breed earlier than those in southern Illinois. Bischoff (1957) reviewed breeding dates for 427 pregnant mule deer (Odocoileus hemionus)from 12 herds repre- senting five California subspecies. There, too, the more northern herds tended to have earlier breeding seasons. Cheatum and Morton (1946) reported that does in southern New York State breed a week later than in northern New York. “For Missouri, Murphy (in_litt., 1962) says that, "the rut ap- parently begins first in southeastern Missouri and progresses in a northwest direction across the state . . . In northern Missouri 17.9% of the females are in breeding condition be- fore November 10; in central Missouri 31.7%.are in breeding condition and in southern Missouri 44.4% are in breeding con- dition before that date." I Lang (1957) reported a difference in breeding dates for mule deer in southern New Mexico and those in northern New Mexico. The southern deer breed a month later than those in the northern-part of the state. Loveless (1959) pointed out a marked divergence in loreeding dates between Everglades and Key whitetail deer of 1?lorida. The ranges of these two herds are'about 100 miles apart and climate conditions are reasonably comparable. Yet tlie peak of breeding occurs approximately five months apart a s Loveless says, 4O Superficially it would appear that these two herds, which are closely related geographically and ap— parently once occupied a continuous range, would breed and drop their fawns about the same time of year. Information shows, nevertheless, that the reproductive cycle in Key deer is more similar to that reported for deer in northwest Florida by Tyson (1954) approximately 500 miles away. It seems fairly evident that range conditions, and undoubtedly a complex of other influences, are significantly related to reproductive cycles, and these cycles are not necessarily determined by length of day, temperature, or other climatic factors and are in part a function of adaptation to environment effects. The genus_9docoileus generally breeds earlier in the northern regions than in the southern regions of the United States (Table 3). 41 Figure 10. Deer breeding dates by regions, Mississippi, 1960-1962. 42 Dec. Jan. Thee. 5, 6, 8, 9, 10, 15, 16, 16, 16, l9, l9, 19, 20, 27, 27, 30 Jan. 8, 9, 18 0 Dec. 22, 30 Jan. 3, 13, 15, 22 Mississippi 12, 5. 11, 17, 20, Dec. Jan. Feb. 16, 19, 23, 18 11, 12, 12, 17, 17, 18, 21, 21, 23, Dec. Jan. Feb. 0 28 2. 14, 3 f6, 27 l) 8) 17, 31 3, 5, 24 8, 9, 27 13 18, 19, 24, 25, 3, 13, 24 \ : 30: 9, 10, 43 AnmmHv c3oum o .>OZIom .uoo HHmuouHCS ooH3oumum AhmmHv ouuoCsHm .oon .Cmol.oon HHmuouHCS CmHumm mmmCoa mCmHmHsoq AmmmH ..uuHH CHV Comsmm .>oz .owQI.>oz HHmuouHCE ooH3oumum m30H hmmma ..uuHH CHV CODHHEmm .>oz .UoQI.uoo HHmuoUHsz ooH3oumum mCmHoCH Ammma ..uuHH aHV csonamo noumzu.>oz HHmumans :Hmnusom Ammmal..upHH CHV CCOCHMU .Uonl.uuo HHmuoanz CHoCDHoz wHOCHHHH AmmmHv mmmHo>on .umom mCOHHmoN HHmuoanz moomHmHo>m ANmmHV CHOCCon 0N .>oz HHmuouHCS meme oEmO msuuHo Amemav cuoaaon m .uoo HHmumanz meme oEmw mHooomo moHHon Amemav cHuumno e .omnImH .>oz m .cmeImH .>oz was: chem oumumuouCH .II.II lawmav season .Hm no .oHomooq .>oz on .Cmbu.>oz HHmDMUMHm oCEsHosB Ammmav .Hm um , . muummmn .umnsmmrmm. .Cmb HHmuxUMHm Choumo3cusom AmmmHV .Hm um .umusmmrmm. .>oz oumq HHmuxomHm munon Ammmav .Hm um Hmummoo .umHsCmCon .umom HHMHROMHm HmHUCoU AmmmHV came Ime a Means .>oz mHHmm HHmuxUMHm Cuoumo3nunoz mmmHv Hones mH .>ozImH .uoo .>ozl.uoo HHmuxomHm maceoo oxmq mHCHOMHHmU AmmmHv mesm H .Cmb 0N .QomIH .oon oHsz HmuuCoo mCONHua AmmmHv Comsmm mIH .Cmb HN .QomION .ooa HHmumuHCS HMHUCouummm mEmanm moUCoHomom oumn mCHooon moumn mCH moHoomm CoHumooq ooCooH>0Hm CmoE Ho OCH Ioooum mo omCmm HMUHCmmumooo Ho oumum Ioooum mo quHom .moumum mN CH msoHHooooO mscom on» you mount mCHoooHn pounomwm .m SE 44 AboumoCsv uanAz s uwwzm omImH .>02 mm .omnIHN .uuo HHmumuHrs cumausom Aewumecsv ucmHuz w uoozm nHIN .>oz 0H .oonImN .uoo HHmuouHCS Cuonuuoz AmmmHv oHomCmS mNIm .>oz v .CmbION .uuo HHmuouHCS CHoCuuoz momnob 3oz Amema ..uuHH mmD oHEmumq .>oz oHS. .Cmbl.uoo HHmuoanz ooH3oumum oHHCmQEmm 3oz Ammma ..uuHH NHL smHHmm H .uwnuom .>oz ma .omduoa .>oz HHmuprgs meHzmumum mxmmunmz omCmm AommHv COmosm 0N .>oz 0N .oonlm .>oz 0H5: COmHm .umz mCmuCoz ANomH ..uuHH mHD mamas: ma .>oz HHmumuHrs meHsmumum .>oz mHHmo AmmmHv anon I.uoo oumq .Cmbl.uoo HHmuopHCS ooH3oumum HusommHz Amosum mHnuv manoz ma .cmb em .nmmImH .ume HHmumuHss cumzusom Ahosum mHCuv wwmmm. mH .ooa m .noMIH .oon HHmuouHCR Cuonuuoz HCmHmmHmmHz AHemHV .Hm uw .COmonHm .>oz .noml.uoo HHmuouH£3 ooH3oumum mDOmoCCHz Ammmav puma qumm a mCHmeb .>oz HHmuouHCS ooH3oumum Amemw...uusa CHV oCHo> NH .oonlh .>oz Hm .oooIH .>oz HHmuouHCS .CHCom Home: “HmmHv oCHo> MH .uonln .>oz HHmuoan3 .CHCom Home: CmmHCUHS AHmmHv CHH lameness e swam mmIOH .>oz HHmumuHrs meHzmumum muuomsnommmmz hmmma ..uuHH CHV RMHmmCmm MNIOH .>oz mN .oonION .uoo HHmuouHC3 oonoumum Aaomav memmcmm mm .omnuom .uoo HHmAmBHBz. meHsmsmum mesa: mooCoHomom oumn mCHooon moumn mCH moHoomm CoHumooq ooCooH>onm CmoE Ho mCH loomum mo omCmm HmOHCmmHmooo Ho oumum Ioooum mo quHom oosCHuCoo m manna 45 ImmmHv mama HA .>02 A .nmmum .uuo HHmumuHaz meHsmumum chcoomHz lemmas onsemao e .uwnuoa .>oz m .ameum .>oz HHmumans oeHsmumum “Homav AUHsemno mmnoa .>oz m .umznom .uoo HHmumans meHsmumum “anode HHHo UCm OEHmmon hNICH .>oz mN .CmoIhH .Hoo HHmuouHCS ooH3oumum MHCHmHH> umoz Aaomav csoum mmuoa .>oz AH .cmenmm .suo HHmuxumHm meHzmumum coumcHamms smoumHm AmmmHv some om .>oz-vm .uoo HHmuouHrz meumsem mmxme mend AHomHv mHBQQ .oonl.uoo HHmuouHCS oEmw omooumo oommmCCoB hmwma ..uuHH :Hv uumsmHum OH .omnuom .>oz .omnI.>oz HHmumpHrz mestumum muoxmn Busom “NomHv mom: .>ozl.uoo HHmuouHCS ooH3oumum ANomHv mom: .oonu.uoo oHsz Cuoummm ANmeV moms .oonl.uoo HHmuxUMHm Cumumoz comouo hmmmH ..uuHH oHsE oCm CHV oHNmeuz 0N .>ozION .uoo HHmuouHsz ooH3oumum muoxmn Cunoz Aeemav cosmos ocm Enumono MNIhH .>oz HHmuouHC3 CHoCusom AmemHL cosmos oCm EnumoCU OHIOH .>oz HHmuouHC3 Cuocuuoz xuow 3oz HHmuouHCS AhmmHv mCmq .Cmbl.oon oCm oHsz Chonunoz AhmmHv mCmq .nomI.Cmb HHmuoDHC3 ChoumoBCusom AHemHV COHmGHHHmm MH .Cmb MN ..HMZION .009 was: OUTSOHMHm 0.0ng 32.4 mooCoHomom oumn mCHooon mouma mCH onoomm COHumoon ooCooH>onm Came Ho mCH Iooonm mo omCmm HMUHCQmHmooU Ho oumum Ioooum mo quHmm COCCHHCOO m magma THE DATE OF SEASONAL ESTRUS IN BOLIVAR COUNTY DEER The presence of a corpus luteum in an ovary indicates that the doe has ovulated and possibly has bred successfully. If ovary collections are initiated early enough and con- tinued over a sufficient period of time, it is a simple matter to establish the date of estrus. The first antlerless—deer seasons in Mississippi were held on the Catfish Point and Merigold Hunting Clubs in Bolivar County December 15 - 22, 1960, and January 3 - 9, 1961, respectively. These hunts yielded 136 adult females. Preliminary examination of the ovaries from these deer indicated, on the basis of corpus luteum counts, that many had gone through heat. In addition, 13 of the January sample contained visible fetuses. It was decided that an earlier fall collection was necessary. Therefore, the 1961 antlerless season for Catfish Point was set for November 11 - 15, inclusive. In addition, the Ashbrook Hunting Club in adjacent Washington County agreed to conduct an antlerless hunt on November 20 - 21, 1961. On these two hunts I col- lected information from 76 females, 67 adults and nine juveniles. A fourth antlerless hunt, at the Huntington 46 47 Point Club, enabled 31 adult females and five fawn females to be collected December 2 - 7, 1961, inclusive. In total, 234 adult female reproductive tracts were collected on antlerless-deer hunts in Bolivar and adjacent washington County covering the period November 11 through January 9 in the years 1960, 1961, and 1962. Of these, 12 were unusable because they were partially destroyed by gun- shot (6), improperly preserved (2), or with one or both ovaries missing due to improper removal of the reproductive tract (4). A further 36 pregnant does were killed by me in the county during February, March, and April of 1960 and 1962. Their estimated breeding dates extended over the 45-day period December 5 through January 18. The average breeding date was December 19 with a standard deviation of nine days. On the January 3 - 9, 1961, antlerless hunt, I col- lected the reproductive tracts from 73 adult does. Thirteen (13) (17.1%) of these animals were visibly pregnant but the calculated breeding dates were not used in calculating the mean because they represented only the earliest breeding dates for that year. These 13 early breeders had bred be- tween December 1 and December 11. No corpora lutea were found in 60 pairs of adult ovaries collected between November 11 and November 22 (Table 4). Many of these ovaries exhibited maturing graffian follicles, however, indicating that ovulations.would have 48 Table 4. The number of adult does, collected on antlerless hunts, by date and the number showing corpora lutea; Bolivar and washington Counties, Mississippi, 1960-1962. Number of Adult Number With Date of Does Corpora Collection Collected Lutea November 11 27 0 November 12 10 0 November 14 l 0 November 21 22 0 December 2 6 2 December 3 7 0 December 5 3 1 December 6 6 1 December 7 6 0 December 15 13 8 December 16 2 2 December 17 9 1 December 18 12 7 December 21 13 6 December 22 ll 7 January 3 21 11 January 4 12 9 January 5 6 4 January 6 13 6 January 7 5 4 January 8 14 12 January 9 3 2 49 occurred within a few weeks. The deer collected on November 21 were taken at the Ashbrook Hunting Club in adjacent Washington County but the collecting sites in Washington and Bolivar Counties are separated by only a few miles. All other deer were taken in Bolivar County. On December 2, 1961, two of the six adult does taken contained corpora lutea. In one of the two specimens the corpora lutea were not completely luteinized. Ovulation in that animal evidently had occurred only one or two days be- fore, probably on December 1. The earliest estrus date in Bolivar County was evi- dently December 1. The earliest established breeding date for 49 pregnant deer from the county also proved to be December 1. Between December 5 and 16, 1961, thirty adult does were collected. The ovaries of 12 of these animals (40.0%) contained corpora lutea. Fourteen (38.3%) of the 1960 and 1962 spring collection of pregnant does had bred between December 5 - 16. These figures are almost identical and further indicate that deer breeding dates did not vary during the three breeding seasons concerned in this study. Eleven adult does were collected on December 22, 1961, and the ovaries of seven (63.9%) contained corpora lutea. 27 (75.0%) of 36 spring collected does had bred be- fore December 22. 50 During January 8 - 9, 1961, 17 adult does were col- lected, and 14 (82.3%) either contained fetuses or corpora lutea. In the gravid sample, 97.2% were estimated to have mated before January 10. Minor discrepancies above can be explained as follows: An attempt was made during the spring collecting period in Bolivar County to kill only does with fawns following them. This obviously gave a sample derived from the breeding popu- lation but was the best method to prevent the killing of antlerless males which were then common. The spring col- lections in Bolivar County therefore were not random samples of the female segment of the herd, but presumably were a random sample of deer from the breeding population. The samples from antlerless hunts undoubtedly included non- breeders since there is no reason to think that hunters were selective of breeding does. In summary, it appears that the earliest estrus in Bolivar County and possibly throughout north Mississippi oc- curs about December 1. About 14% of adult does experience their first estrus of the year during the period December 2 through December 7 and 82% of the adult does in the county show corpora lutea or fetuses by January 9. Perhaps 15% of adult does do not breed in a given year since samples from the breeding population taken during the gestation period indicate that 97.2% of animals which breed are mated by January 10. 51 The deer ranges from which these does were collected in Bolivar and adjacent Washington County were seriously overpopulated as evidenced by winter browse studies (Noble, 1960). No fall and winter deer collections were made in south Mississippi but from established breeding dates (above) the first estrus in the southern region must occur about December 15. BREEDING BY FAWNS In New York, according to Morton and Cheatum (1946), "the incidence of breeding among doe fawns, which at the time of conception were six months old, indicates that a high percentage of such deer are capable of breeding successfully." a. Mississippi Fawns 37 female fawns aged four to nine months, were col- lected during this study. Nine were taken in November, 13 in December, four in January, four in February, six in March and one in April. None carried featuses and all ovaries ap- peared quiescent (Figure 11). Neither corpora lutea nor well- developed graffian follicles were found. The evidence is that few, if any, Mississippi does experience estrus before they are at least one year old. b. Incidence of Fawn Breeding in Other States Teer (1959) examined 13 fawns from the Edwards Plateau in Texas but found only one of these animals with a corpus luteum. Graffian follicles were well developed in several of the fawns, none of which was older than six 52 53 months, but ova had not ruptured from the ovaries. Thomas (1962) collected 24 fawns from the same area and reported that two contained corpora lutea. He pointed out that fawns may breed later in the season than adults. Lueth (in_litt., 1962) reported one incidence of fawn breeding in Alabama. Brunette (1957) found no pregnant fawns in Louisiana. Mangold (1958) found 14 of 55 New Jersey fawns to be pregnant. According to Sweet and Wright (undated), about 40% of the fawns in New Jersey breed during the first rutting season after their birth. I Robb (1959) found that 37% of his Missouri sample of 4-7 month-old fawns had mated and attributes this to above— average nutrition. Erickson §t_§l. (1961) estimated that 20% of Minnesota fawns breed annually. Severinghaus and Cheatum (1950) examined 346 New York fawns six to eight months old and found 75 to be preg- nant. Chadwick (1958) found six of 23 West Virginia fawns to be pregnant. Taber (1953) examined four blacktail fawns (Odocoileus hemionus) in California and found no evidence of breeding. Bischoff (1958) studied 20 California mule deer fawns and found no evidence of ovulation. Lassen _E El. (1952) re- ported that ovaries of California mule deer fawns showed no indication of follicular maturity. Apparently, whitetail fawns in New Mexico do not breed (Lang, 1957). Harrington (1961) reported no incidence 54 of fawn breeding in New Mexico mule deer. However, Snyder (1959) collected 100 mule deer fawns in New Mexico and found one to be pregnant. Brown (1960) later collected 19 fawns from Snyder's study area and reported that the ovaries of four contained corpora lutea. Verme (1961) reported that only about 5% of the fawns in the Upper Peninsula of Michigan breed and credits this low percentage to the severe winters of northern Michigan. Figure 11. Immature reproductive tract from a six-month—old female fawn collected March 14, 1962, in Bolivar County, Mississippi. This animal was typical of all female fawns collected in this study. The smooth, white, relatively flat, quiescent ovaries are visible. Copiah Wildlife Management Area Laboratory, Barlow, Mississippi, May 3, 1963. Photograph by W. H. Turcotte and the author. 55 U Z wONJJOU ZOJW .OU >J&n_3m I_mn eszzmm ona¢H>mn eszzmm emenzeem zemz omenzeem 24m: HmmHmmHmmHz meoom HmmHmmHmmHs memoz o.ooa mm o.ooa om mamuoe Ts m 0.0 o 3 umssouamm I m “mesmueom Ham 0 o.m H m umnsmuqmm I om amnesfl 0.: m 0% N ma umsmse I o umsmmmw H.m~ e o.vH A m umsmse I mm N458 Iw.em H o.em ma . mm >Hse I m sash n.e my o.ev mm , m ease I mm wage ezmommm mmmzez ezmommm semapz HmmHmmHmmHz meson HmmHmmHmmHz memos nonmA mszzmm nonmm eszon oszzem mmon seamen eZHEDn ezazzee mmon .mema .HomA .ooma .HemHmmHmmHs cH oouooHHoo mooo oH>mHm on How Amoxunso topmolxomn Ecumv COHHoQ mCHC3mm ooumEHumm .m OHnt Figure 12. Reproductive tract of a 1.5-year-old doe con- taining a single fetus as it appears_in situ. Copiah Wildlife Management Area Laboratory, Barlow, Mississippi, May 3, 1963. Photograph by W. H. Turcotte and the author. JI..I>'. fl I‘D-III MINIMUM AND MAXIMUM BREEDING AGES OF MISSISSIPPI DOES Most Mississippi hunters are of the opinion that old does do not breed. Any deer manager in his association with hunters will hear the inevitable cliches, "dry doe," "barren doe," “single doe," "maiden doe," and "blue doe." These terms are used collectively in reference to female deer which, supposedly, do not produce offspring. To a hunter, any doe may be "old." Severinghaus and Cheatum (1956) stated that 10-year- old individuals are of little consequence in most whitetail populations. Jenkins and Bartlett (1959) stated: As far as we know, there is no such thing as a "barren doe" because of age. Sweet and Wright (undated) wrote: It was found during the course of this study that age did not affect the breeding ability of the does in New Jersey. It appears that they breed just as long as they live and that the older animals have just as many offspring as the younger animals. The two oldest animals taken in this study were esti- mated to be between 9.5 and 10.5 years of age. One was carry- -ing twins and the other would have given birth to a single male. Of the two 8.5-year-old animals, one was carrying twins and had two fawns following and the other was carrying 62 63 a single fetus. The five 7.5-year-old animals collected in spring were all pregnant and carried an average of 1.50 fetuses each, which was better than the 1.42 average for all pregnant does examined. Six 6.5—year animals were ac- companied by young and also were carrying an average of 1.33 fetuses each. Of the 83 adult does collected in late spring, only seven were apparently unbred. The ages of those animals in years were: 1.5, 1.5, 2.5, 3.5, 5.5, 6.5, and 9.5. Although without evident fetuses, the ovaries of the 9.5-year-old animal contained corpora lutea when collected on March 8. The 3.5-year—old and one of the 1.5-year-old ani- mals showed corpora lutea on February 25. The other four animals, three of which were collected on March 14, did not display corpora lutea. There is little, if any, fawn breeding in Mississippi. The minimum breeding age for deer is approximately 1.5 years and the animals drop their first fawns when about two years old. Six of eight does in the 1.5-year-old class collected in late spring were gravid. All carried a single fetus (Figure 12). There is no maximum breeding age. It appears that whitetail does in Mississippi breed and produce off- spring as long as they live. 64 a. Age of Doe as Related to Date of Breeding So far as could be determined, no age class tended to breed earlier or later in the year than any other age class. December 1 was the earliest breeding date recorded for north Mississippi. One 3.5-year-old animal and one 4.5- year-old animal was estimated to have bred on that date. The earliest breeding date in south Mississippi was December 13. A 2.5-year-old animal was estimated to have bred on that date. The latest breeding date for south Mississippi (February 24) occurred with a 4.5-year-old animal. The latest breeding date in north Mississippi (February 3) was for a 2.5-year—old animal. The youngest breeding class, the 1.5—year—old animals, bred during the height of the rut in both regions. The sample of old does (6.5 years plus) was limited in size, but the 15 collected had bred neither noticeably earlier nor later than any other age class. BIRTH RATES IN MISSISSIPPI DOES Fawn production in a herd is best measured by de- termining the exact number of fawns born to a given number of does. This is a difficult procedure except in semi-wild or tame herds. For that reason the deer manager must rely upon fetal counts which incurs the danger of error induced by prenatal mortality. If pregnant deer are collected throughout the gestation period, however, sufficient infor- mation on prenatal mortality should be available to enable final calculations to be corrected for fawns lost prior to birth. a. Factors Influencing Birth Rates in Deer Perhaps the three factors that influence birth rates more than others are (1) age of the doe, (2) conditions of the winter range, and (3) population density. Eberhardt (1960) has shown that reproductive rates of white-tailed deer in Michigan vary inversely with population densities. A number of observers have reported that does on good range produce more fawns than females in poor habitats (Banasiak, 1961; French t 1., 1955; Morton and Cheatum, 1946; Verme, 1962). 65 66 Many animal Species have been shown to reproduce more successfully when at a low rather than high density. Higher percentages of adult females also engage in reproduction under uncrowded conditions. This phenomenon has been demon- strated with moles under laboratory conditions, by Clarke (1955) and for muskrats (Ondatra_zibethicus) in natural con- ditions by Errington (1954). Patric (1962) observed the same phenomenon in the red-backed mouse (Clethrionomys Sp.). Age has an effect on birth rates, for fawns, if they breed, nearly always give birth to a single fawn (Banasiak, 1961). The 1.5-year-old age class, if breeding for the first time, usually also produces only one fawn (McDowell, 1962). Higher birth rates are found in the older age classes (Severinghaus and Cheatum, 1956) as has been de- scribed above for Mississippi deer. b. Average Number of Fetuses Per Doe The average number of fetuses per doe is a good indi- cation of fawn production. If the average number of fetuses per doe and population densities are known, annual herd increment can be estimated. Though McConnell and Dalke (1955) have shown that there is considerable variability from year to year in fawn production in Idaho mule deer, con- tinuous studies are impossible. The deer manager must rely upon carefully planned studies and apply these findings with discretion from year to year. 67 Statewide Sample 126 fetuses were taken from 89 adult does collected throughout Mississippi. The average number per doe was 1.42. This is low as compared to other states (Table 6). In com- piled studies from 22 states and one Canadian province (Table 6), 2,250 gravid animals were examined and 3,701 fetuses identified. This is an average of 1.64 fetuses per pregnant doe when whitetail, mule and blacktail deer are combined. The average is 1.65 fetuses per pregnant doe for whitetails alone. Most Mississippi does, however, were from overpopu- lated ranges. Higher fawn averages may be expected on less crowded ranges of the state. Fawn Production on Mississippi River Bottomlands as Compared with the Longleaf Pine Belt Collections on Mississippi River Bottomlands (batture forest of Bolivar County) and from the longleaf pine belt were both made largely on overpopulated ranges. The Bolivar County collection, however, represents deer from a highly fertile, alluvial soil while data for the longleaf pine belt represent animals on a sandy, infertile soil type. 41 pregnant does from Bolivar County were carrying 57 fetuses, an average of 1.39 fetuses per doe. 20 pregnant does from the longleaf belt contained 27 fetuses, an average of 1.35 fetuses per gravid female. This is a superiority of 68 Amoma ..uuHH mHD magmao on.H om me HHmuwuHrz oHumuco Hammad meme os.H oooa mmm HHmumuHrz chcoomHz lemmav roasemao oe.a Hes mm HHmumuHrz mflcemnH> ummz Amemav masons em.H «ma mAH HHmumuHss mmxme loomgc “was mm.a Hem omm HHmumuHas mmxma AmmmHv Heme NH.H Hem meg AHmumuHaz mmxma hwmev mH3oq. mh.H h v HHmuouHCS oommoCCoB “Nema ..ABHH :HV sumsmHum os.A HA 0H Hemumans muoxmn Busom ANomH ..uuHH qu mCmq ¢S.H HHmuoanz. mHCm>H>mCCom ANomH ..uuHH mag oHnCoMuz o>.H HHmuouHCS muoxma Cunoz lemmav assuage a mamamcHAm>mm mm.a ens mag HHmuwans Amos 3mz lemumecsv uanus s pmmsm em.H eae mam HHmumpHas Ammume 3mz Amemg ..uuHA NHL mesmumq os.H Hflmumusaz mHHBmEEmm 3mz Amoma ..BAHH mHD mmasmm om.A am as HHmsmuHaz mammunmz Asmara mHauV warez me.H GNH mm HHmumuHrs HemHmmHmmHs Ammmmw.nmsoconoz mm.H om AH HHmumanz muuwmaaommmmz Amema ..uuHH cHV memmcmm HH.H «em m¢H HHmumuHrz mchz Aaomav xmemmcmm om.H AHA mo HHmumqus oases “Amway csoum oe.H A m HHmumuHrz memHmHsoq laomav upmAUHm s soaumm oH.H mm ma HHmumsHas meHAon Amemflv auoaaon e~.A om SH HfimumuHaz meHAon AHemHv apmsq oo.H em ma HHmumuHaz msmnmaa eon oHCEmm oHQEmm oUConomom oH>mHo Hem CH CH moon moHommm oUCH>0Hm MOMSHOM MO wwwsumh 0H>MHO HO wfimum .oz ommuo>¢ mo .02 mo .02 .moUCH>oHQ oCm woumum msoHHm> Eoum oouuomou mm woo oH>mHm mom momsuom mo HonEsC ommuo>¢ .o manna 69 hm.H mme mom 0H5: mo.H oHNm HemH HHmuoanz we.H Hoem ommm moHommm HHe mqmeoe HHSmHV czoum mm.H «OH be HHmuxomHm aoumcHsmmz AmomH ..uuHH NHL mHNcmxuz ~¢.~ mHss muoxmn auuoz HHemHV coumcHnumC me.H oe mm mHsz oonms 3mz HommHv Cowosm on.H mm om oHsz MCmuCQS AmmmHv mummm mo.H eOH em mHsz manages Amemww.CHuumno mh.H em we oHsz MHCHOHHHmU AmomH ..uuHH :Hv mHamHm HH.H we om mHss mHauomHHmo AmmmHv Hesse om.H em eH mHsz chNHue won oHQEmm onEmm mUCoHomom oH>mHO Hem CH CH moon moHommm oUCH>0Hm momsuom mo momsuom oH>mH0 Ho oumum .oz ommuo>< mo .02 mo .02 oosCHuCou .0 OHQmB 70 only 0.04 fawns per pregnant doe for the fertile batture forest over the infertile longleaf belt. Although on the basis of general observations, the population density of deer was much lower on the longleaf area, here again is evi- dence that regardless of absolute density, density with re- spect to carrying capacity is more important in determining reproductive success. Twins are supposed to be more common in deer on higher quality range (Cowan, 1956). 16 of 41 gravid does from Bolivar County and 7 of 20 from the longleaf belt were carrying twins. From chi-square tests, there was no reason to believe that there was a difference in the proportion of twins between Bolivar County and the longleaf belt at the 1% level of confidence (calculated chi-square = 0.00051). Birth Rites as Related to Range Condition A number of investigators have pointed out that an overbrowsed deer range results in a lowered rate of repro— duction (Park and Day, 1942; O'Roke and Hamerstrom, 1948; Cheatum and Severinghaus, 1950). Of the pregnant deer taken for this study, nine were from good range, 11 were from fair range and 69 were from poor range. Good range refers to an area where food is plentiful throughout the year and where the deer population is well be- low the range carrying capacity. On fair range the deer herd 71 is approaching overpopulation and some competition for food exists in early spring. Poor range is overbrowsed, native foods are scarce in late winter and early spring and deer numbers exceed the range carrying capacity. Pregnant does from good range in Mississippi were carrying an average of 1.56 fetuses each, and the does on poor range averaged 1.36 fetuses each. These data support the evidence that does on overstocked range produce less fawns than does on properly—stocked to understocked range. c. Frequency of Pregnancy The frequency of pregnancy is the percentage of does that become pregnant during a given breeding season. Albegglen and ROppel (1959) prefer “pregnancy rate," Sweet and Wright (undated) use "incidence of pregnancy," and Brown (1957) proposed the term "frequency of fertilization." The need for a standard code of nomenclature in the wildlife pro- fession has been discussed by Hill and Kimball (1948). Statewide 83 adult does were collected in late spring (when breeding does normally have visible fetuses) and 76 (91.6%) were carrying young. This is probably higher than the aver- age pregnancy rate for Mississippi deer since some attempt was made to collect only females from the breeding population. 72 In general (Table 7), the frequency of pregnancy throughout the country in the genus Odocoileus averages 92% to 93%. Some small samples revealed a frequency of pregnancy of 100%. Mississippi RivergBottomlands 39 adult does were collected on the Mississippi River bottomlands (of Bolivar County) in late spring and 36 were pregnant (92.4%). The three non—pregnant does taken on March 14, 1962, had no corpora lutea present. Evidently only a few animals would have been unproductive in the 1962 fawning season. Longleaf Pine Belt 20 (95.2%) of 21 adult does taken in the longleaf region in late spring were pregnant. The one nongravid animal was a 9.5-year-old doe killed March 9, 1962, on the Leaf River Game Management Area in Perry County. The right ovary contained a well-develOped corpus luteum. Whether this meant a late breeding date, a recurrent estrus, or early prenatal mortality was uncertain. Upland Hardwood Forest All seven adult does collected in the upland hardwood forest (Lafayette County) were heavy with young. 73 .emumum usz, m.em HASH 0H5: m.Hm Moe mHHmuouHCS deBOB HHomHV csoum m.em mm HHmuxumHm coumcHammz AHmmHV coumCHHumm o.¢h mm oHsz OUonz 3oz HoomHv ezoum c.00H oe mHsz oonms 3mz HmmmHv seesaw 5.0m Hom mHsz oonmz 3mz HemmHV cowesm o.mm om 0H5: mcmucoz HmmmHv mummm e.Hm on mHss mcmucos HommHv :msHoe m.~H meH mHsz oemHoHoo Heemmw.cHuumao o.OOH me mHsz chHOHHHmo HmemH ..uuHH ch mHamHm m.~m mm mHss chHOHHHmo Ammmww.me3m m.Nm mmm 0H5: MCONHH< HmemH ..HHHH ch mama ~.om s HHmumanz chm>Hchcmm oHsz oCm HmomH ..uuHH NHL wHuemsos o.me . HHmumuHas muoxmn nuuoz HmmmHv eHomcmz. e.om mmH HHmumquz Ammume 3mz Hemumecsv HamHuz s ummzm «.mm eoH HHmuouHaz Ammume 3mz HmmmH ..uuHH NHL smHHmm o.OOH HH HHmumuHaz mxmmunmz Hmeaum mHnuv oHnoz o.Hm mm HHmumanz HmmHmmHmmHz AmomH ..uuHH mHo mauo> 0.0m . HHmumuHaz ammHaoHs AmmoHv C30Hm ¢.Hn h HHmuoanz mCmHmHsOH HmomH ..uuHH cHV csoaHmo o.OOH . HHmumuHaz mHocHHHH moCmCmon poCHmem ooCoHomom mo moon moHoomm oumum NUCosvon uHso< mo Honssz “II I .moumum msoHHm> Eoum omunomou mm Hoop CH NUCmCmon mo mucosvmnh .5 oHnt 74 d. Ovulation Incidence The number of corpora lutea in the ovaries of preg- nant deer is indicative of the number of eggs ovulated during the preceding estrus period. Where two eggs were ovulated, two corpora lutea would form even though only one egg developed into a fetus. When fertilization occurs, all follicles from which ova were expelled become luteinized. The ovulation incidence is defined as the ratio of the total number of corpora lutea in the ovaries to the total number of pregnant reproductive tracts. It is the average number of eggs ovulated per doe during the estrus period in which conception occurred: Number of Corpora Lutea in Ovaries of Ovulation _ . Incidence — GraV1d Tracts ‘_ Number of GraV1d Tracts Pimlott (1959) used the term "ovulation rate" and Sears (1955) preferred "corpora luteal incidence" in re- ferring to "ovulation incidence." Factors Influencing the Ovulgtion Incidence Nutrition and age affect the ovulation incidence (Cheatum and Severinghaus, 1950). On inadequate diets, does produce fewer ova (Longhurst, gt El°: 1952). Sears (1955) found the lowest ovulation incidence among mule deer of the 75 one and two—year age classes. A diet low in protein and phosphorus causes a low ovulation rate in sheep (Taber and Dasmann, 1958). Ovulation Incidence in Mississippi Deer Corpus luteum counts were possible in 78 pregnant does collected throughout the state. The does averaged 1.58 corpora lutea each. 35 (44.9%) had ovulated only one ovum while 41 (52.6%) had produced two eggs. In two does, three corpora lutea were recorded. No single ovary contained more than two corpora lutea. 20 deer from the longleaf pine belt had an ovulation incidence of 1.50; 41 batture forest deer (Bolivar County) averaged 1.46 ova per doe. There was no significant differ- ence between these averages, yet the two areas show a marked difference in soil fertility and deer carrying capacity. The batture forest supported one deer per six acres while the longleaf belt carried one deer per 30 acres. The deer from both areas, however, were taken on overbrowsed ranges. 17 additional does were collected on understocked ranges (7 from the upland hardwood forest of Lafayette County and 10 from the shortleaf—loblolly pine forests of Choctaw, Noxubee and Copiah Counties), and they had an ovulation inci- dence of 1.94. These data demonstrate that regardless of soil fertility, ovulation incidence falls when overpopulations occur . 76 Although several workers have reported a lower figure for mule deer (Table 8), the statewide ovulation inci— dence (1.58) for Mississippi deer is the lowest average re; ported for whitetails. It is believed, as in some other states (see Table 8), that this is due to generally over- populated deer ranges. e. Reporductive Efficiency Reproductive efficiency (the "fertilization rate" of Taber, 1953; and the "parturition frequency" of Provost, 1960) may be expressed by the proportion or percentage of ovulated eggs which become embryos. If a doe is carrying a single fetus and her ovaries contain two corpora lutea, she is reproducing fawns at 50% of her ovulation potential. Where it can be assumed that reproductive efficiency is constant for a given population, corpus luteum counts can provide information to estimate rates of population increase from year to year. Several studies have shown that does produce slightly more ova than fetuses during the estrus period in which con- ception occurs (Taber, 1953; Cheatum and Morton, 1946; 'Bischoff, 1958). Eggs that do not become fetuses may be re— sorbed or be lost due to failure of sperm to reach the egg, failure of the fertilized egg to implant, or to a combination of these factors. 77 .mCoHuHoCoo omCmu HO\oCm omm Co mCHoComon HHOOHO asoum H¢.H me mHss coumcHnmms HoomHv Czoum mo.N ow oHsz OOonz 302 AHmmHO coumcHuumm m>.H mm mHsz OUmez 302 AmmmHO seesaw H~.H HOH 0H5: OUmez smz ANOOH ..HHHH mHO mHnemxos .m~.mumm.O oHsz muoxmo Buuoz HmmmHv mumom mh.H mo OHCZ mCmuCoz lmmmHO .Hm.mm.cwmqu O¢.H mHsz chuomHHmo HOmmHO HHHO .OO.HIHN.H Hem HHmuoanz chHmuH> Hams HmmmHO qusemno OO.H He HHmumans mHeHmuH> ummz ANOOH ..uuHH mHO unmsmHum OO.~ OH HHmumuHas muoxmo ausom AOmOHV mamamcHumsmm new ssummao HO.HIHH.H HHmumans snow 3mz lemumecsv uanuz new uwmzm OO.~I©O.H HOH HHmumuHrz Ammume sea ANOOH ..HHHH mHO mHuamxos .O~.~IOm.H HHmumuHas muoxmnnauuoz Asesum mHnuO mHnoz Om.H me HHmumuHaz HmeHmmHmmHz HmmOHO amgocoouz .OH.~IOO.~ HHmumuHaz muummsnommmms HHOOHO memmcmm .em.HIee.H HHmumuHas mchs AHmOHO csoum OO.H m HHmumuHas mcmHmHsou HHOOHO semen HO.H mH HHmumsHaz mamAmH< oUCouomom oUCmoHoCH oNHm moHoomm oUCH>oum COHHMHC>O onEmm Ho oumum .moHuHHOCusm msoHHm> he oounomou mm msoHHooooo msCom on“ CH OUCOoHoCH CoHumHs>O .O mHnme 78 Statewide Reproductive Efficiency 78 pregnant does from throughout the state carried 110 fetuses and 123 corpora lutea yielding a reproductive ef- ficiency of 89.4%, 41 Bolivar County (batture forest) gravid does carried 57 fetuses and showed a reproductive efficiency of 95.0%, while 20 pregnant does from the longleaf pine belt carried 27 fetuses with a reproductive efficiency of 87.1%” Ovulation incidence and frequency of fertilization is slightly greater in the longleaf belt than in the batture forest but reproductive efficiency and the average number of fawns per doe is higher in the batture forest. It is not known whether these matters are related to the higher fertility of the Bolivar County soils. Reproductive efficiency rates in other states range from 94% in California mule deer (Taber, 1953) to 78% for a small sample of Louisiana whitetails (Brown, 1957). In part, the moderate reproductive efficiency in Mississippi deer may balance the low ovulation incidence. f. Number of Fawns Following Gravid Does and Number of Fetuses ip utero Many of the pregnant does killed in the spring were ambushed at food plots. Some were observed for over an hour before they provided a favorable shot. For 28 pregnant does from the batture forest and 16 pregnant does from the long- leaf pine belt it was possible thus to determine the number of fawns following a particular doe. 79 No does later determined to be 1.5 years old had fawns following. The 2.5-year-old age class was expected to have only one fawn following since they had probably bred for the first time as 1.5—year-olds. A 1.5-year-old deer breed- ing for the first time usually produces only one fawn (McDowell, 1962). Eleven of 12 2.5-year-old gravid does col- lected in the batture forest had only one fawn following. One such female, however, was followed by two fawns. Three of four 2.5-year-old does from the longleaf pine belt were carryingaasingle fetus and one carried twins. However, only one of these animals had a fawn following. The other three does either did not breed as 1.5-year-olds, or had lost their fawns. These does could have had fawns, how— ever, that were not observed. The 28 gravid does from the batture forest carried 44 fetuses and were seen to be followed by 36 fawns. The averages of 1.29 fawns per doe and 1.57 fetuses per doe indi- cate about an 18% postnatal mortality. However, after cor- recting for the 2.5-year-old animals which, regardless of the number of fetuses_ig.ggggg, were expected to have only one fawn following, the postnatal mortality is 8.4% (exclud- ing any prenatal mortality and assuming that the productivity of these does remains constant from year to year). The 16 does from the longleaf belt were followed by 15 fawns. The does carried 21 fetuses, an average of 1.31 fetuses per doe and 0.94 fawns per doe. After correcting 80 for the 2.5-year-old class these data indicate a 17.6% post— natal mortality (under the same assumptions mentioned above). .Apparently postnatal fawn survival is higher in the batture forest than in the longleaf pine belt. g. Age of Doe as Related to Number of Fetuses All of the six does in the 1.5—year—old age class were pregnant; each carried a single fetus (Table 9). Twins were more common in the 2.5-year-old does than any other age class: 60.7% of the 2.5-year-old animals carried twins. Doubtless, in part because of their high rate of twinning, 2.5-year-old animals carried an average of 1.61 fetuses each, the highest in any age class. Does older than 4.5 years carried an average of 1.34 fetuses each. Fawn production was higher in the 2.5 and 3.5-year-old animals than in any other age classes (Table 9). No triplets_ig_gt§£g were observed. In seven years of field work in Mississippi, I observed only seven instances of three fawns following a doe. On May 8, 1962, Area Manager Tate White informed me of a large doe killed by an automobile in Oktibbeha County which, it developed, carried three fe- male fetuses. Chadwick (1958) reported that only one of 35 West Virginia deer had triplets. Benasiak (1961) found that 5% of Maine whitetails carry triplets. Teer (1959) reported two of 163 pregnant does carrying triplets. Later Teer 81 .xmw on HHmEm ooaes .ouous mw.oo>uomno one? 0C50> onCHm Ho mCH3u xHCOe mm. eN 0 NH mH NH HH 0 0.Ne mm mHmuoa 0m.H mm. H H 0.0m N m.m 0m.H 00.0 H H 0.0m N m.m 0¢.H 00. N H N 0.0e m m.n mm.H 00.0 N H N H m.mm 0 m.0 00.H 00.H H H m.m mN.H 0m. N H m m N H H m.nN 0H m.¢ me.H mO. e m H e m e O.Ne Hm m.n H0.H H0. v e 0 H 0 e m n.00 0N m.N 00.H 0m. N N N 0 m.H won Hem mCH3B mmmHU 004 momsupm monEom mOHmCHm mCHze monEom monz ouHmommo mOHmEom mOHma mCHmnnmU mom CH «0 mo . mmMHU moon Honssz COHuHom eeC30CvHCD xom monCHm mCHBB mod CH mo. ommuo>¢J Ioum. neon mo Honfisz womsuom mo xom emmmuCooHom "kW lfll .NOOHIOOmH .HmmHmmHmmHz aH empowHHou Homo oH>mum 00 Comm mama .momsuom mo xom 0Cm HonEsC ou ooHMHeH mm won «0 00¢ .0 OHnt 82 (1960) found one of 220 Texas whitetails carrying triplets. Thomas (1962) examined 115 pregnant whitetails in Texas and detected no incidence of triplets. Swank (1958) found no triplets in 16 Arizona mule deer. Hudson (1959) reported that 3% of the 50 gravid mule deer he autOpsied contained triplets. h. Functioning of the Right and Left Ovary Reece and Turner (1938) reported that bovine ovu- lation occurs 60.2% of the time from the right ovary. Salis- bury and Van Demark (1961:84) speculated that the right ovary functions more frequently than the left in cows be— cause of the anatomical location of the rumen and its close proximity to the left ovary. These authors theorized that the gas-filled rumen may slow the function of the left ovary by exerting sufficient pressure to lower the blood flow to the left ovary. No one seems to have tested this in deer. In my sample 64 does had ovulated (82 ova) only from the right ovary, 59 does had ovulated (73 ova) only from the left ovary, and 28 does had ovulated from both ovaries (30 ova from the right and 29 from the left). Collectively, there- fore, 151 does had ovulated 112 ova from the right ovary and 102 from the left. The chi-square test indicated no sig- nificant difference at the 1% level between the number of 83 eggs ovulated by the two ovaries (calculated chi-square = 0.4672). According to this sample, ovulation in Mississippi white-tailed deer occurs as often in one ovary as it does in the other. Figure 13. A single white-tailed deer embryo. The right ovary contained a well—developed corpus luteum. The left ovary did not produce an ovum. Copiah Wildlife Management Area Laboratory, Barlow, Mississippi, May 3, 1963. Photograph by W. H. Turcotte and the author. 84 0| CAROLINA BIOLOGICAL SUPPLY co. .......... ILON COLL‘OI. N. C. HAHN A. Figure 14. A white-tailed deer embryo about 28 days Old. COpiah Wildlife Management Area Laboratory, Barlow, Mississippi, May 3, 1963. Photograph by W. H. Turcotte and the author. FETAL SEX RATIO Of 126 fetuses collected during this study 86 were Old enough that external sexual organs were clearly visible. Of these 39 were males and 47 females, a sex ratio of 45:55. The chi-square test, after correcting for continuity, indi— cated that there was no significant difference between the proportion Of males and females at the rx level from what would be expected by genetic theory (calculated chi-square = 0.57; tabled chi-square, one degree of freedom at 99% level — 6.63). a. Uterine Sex Ratio in North Mississippi Compared with South Mississippi The sex ratio of 15 fetuses from South Mississippi was 60:40 while 71 from North Mississippi had a ratio of 42:58. Chi-square tests, after correcting for continuity, ixuiicated that neither of these ratios were significantly different from the eXpected 50:50 at the 1% level (Calcu- lated chi-square for the southern sample = 0.27; for the northern sample = 1.41) . b. Sex Ratio in Twins and Singles Of 29 sets of sexable twins from throughout the stuate, six were twin males, 11 were twin females, and 12 were 86 Figure 15. Twin fetuses in utero about 88 days after con- ception. The external genital organs are plainly visible. The fetus on the left is a female. The one on the right is a male. Copiah Wildlife Management Area Laboratory, Barlow, Mississippi, May 3, 1963. Photograph by W. H. Turcotte and the author. l lav-.1. . ......- OU )Jllam J(U.8Jo.m (2.401(0 Figure 16. A white-tailed deer fetus about 140 days old. The black spot on the head is the potential site Of the right antler, but these spots are found on both male and female fetuses. Copiah Wildlife Management Area Laboratory, Barlow, Mississippi, May 3, 1963. Photograph by W. H. Turcotte and the author. ... 1:1... , . ,, ,. I." .2. .2 ,. , .52.: . _ . . y . — L _ _ _ . _ . _ L _ M w _ . , __L.. ,M,.., ,.., vnOQFODUfl dcfiaflfiomV-u . 14:51:: . .. .: ...:_..... kl... .. ...... , 1 is... _ .. E: IE: ., ..L , £1 , : in; 2.56:3 . _ 89 twins of opposite sex. A calculated chi-square, after cor- recting for continuity, of 0.047 indicated that there was no significant difference between the proportion of male and female twins at the 1% level from what would be expected by genetic theory. The same statistical test was used to test if there was a significant difference between the proportions of male, female and opposite sex twins. A calculated chi-square of 2.14 indicated that the observed proportion of male, fe— male, and opposite sex twins do not differ significantly at the 1% level from what would be expected from genetic theory. 52 of the 89 gravid does collected in this study were carrying a single fetus and 28 of these were deve10ped well enough to determine sex. The 54:46 ratio was not sig- nificantly different at the 1% level from the 50:50 expected by genetic theory. c. Fetal Sex Ratio as Influenced by Range Conditions Gerstell (1936) reported that female fawns exceeded males by about a two-to-one ratio on areas of heavily over— browsed deer ranges in Pennsylvania. In this study 6 pregnant does from good range carried 6 male and 4 female fetuses: 8 does from fair range carried 4 males and 9 females and 43 does from poor range carried 29 males and 34 females. None of these sex ratios differed significantly from a 50:50 sex ratio. 90 d. Uterine Sex Ratios Reported in Other States The uterine sex ratio in deer is frequently in favor of males (Table 10). Severinghaus and Cheatum (1956) re- ported a sex ratio of 54:46 for 4,096 whitetail fetuses col- lected in 11 states. McDowell (1962) reported a ratio of 52:48 for 2,759 whitetail fetuses from eight of the north- eastern states. McDowell's data indicate a statistically significant difference between the percentage Of male fetuses carried by precocial fawns and the percentage carried by all other age classes combined. 91 AHOOHO czoum OmuHO mHH HHmuxomHm assumes AHmOHO NHHOO OmueO HH HHmuxomHm coumcHamms HHOOHO coumcHuumm Ovuem mm mHss mOHBoumum oOmez 3mz AmmOHO mumwm neumm Hm mHsz wmcmm cemHm .umz HmmmHv COmosm omuom 00 OHOS omCmm COmHm .umz OCmuCoz AmwOmw.cHuumao Oeuem eO mHsz ANmOHO .Hm pm .mmmmmH meumm OOH mHss cums mHNoo ANOOH ..HHHH NHL mHanm mOumm Oe mHss Nuance commmq chnomHHmo ANOOH ..HHHH NHL HumHO OOHNm em HHmumuHrz meHzmumum oHumuco HmmOHV mHmm meumm OHOH HHmumans meHzmumpm chcoomHs AmmOHO HOHzemno OOHOe NeH HHmumuHes weHsmHmum mHOHOAH> umms HHomHv mH3Oq mNumN e HHOHOHHCZ OOH< oEmo mmooumo oowwOCCoB ANOOH ..uuHH NHL OOmH Oeuem HHmumuHrs meHzmumum chm>Hchcwm AmmmHO OHomcmz Nmume HON HHmumans meHsmumum mxmmunmz Asesum mHBuO mOHeoz mmume Ow HHmumuHes mOHsmumum HmmHmmHmmHz II. OHsmCHCom ANOOH ..HHHH cHO 05m> OmuHe HOH HHmumuHas Hmon rusom mHsmCHCOm ANOOH ..uuHH HMO maum> eeuOm MHH HHmumpHns Amon auuoz ANOOH ..HHHH HO manm> meumm OOe HHmumuHas mHsmchmm swam: cmmHAOHs ANOOH ..uuHH www.memmcmm meumm mm HHmumuHrs meszumum wchz ANmmH ..puHH CH0 COOCHOU mwuNm HHODOHHCB oonoumum mHOCHHHH ANOOHO cHOBaOHm Omuee OH HHmuosHas mane mama mHomomo ANOOHO :uoaaOHm Oeuoe OH HHmuouHas mane mamo mssuHo HHOOHO upwHOHm ecm onumm Heumm mm HHmumuHas meoosumHm meHHOHm AOmOHO cmmsmm Oeuoe ON HHmumuHrz Hmuucmoummm mamgmHm OOCOHomom OHmEOEAOHOS OHQEmm CH mOHOOQm CoHumOOH OOCH>OHm oHumm xom momsuom HOOHCQmHmooo Ho oumum mo HOnEOZ .mOOCH>OHm UCm moumum msoHHm> How oouuomou mm Homo CH moHumH xom OCHHOHD .0H OHQOB PRENATAL MORTALITY One case Of prenatal mortality was Observed in 89 does carrying visible embryos. In a 7.5-year-Old doe, killed March 5, 1962, in the refuge of the Leaf River Wild— life Management Area, one fetus was dead and the second ap- peared normal. It was apparently alive and helthy up until the time of the doe's death (Figure 17). The right ovary contained two well-formed corpora lutea. The dead fetus was in the left horn Of the uterus. The surrounding embryonic fulids were cloudy. It did not appear that the fetus was being resorbed. The fetus was 21.40 mm long and evidently died about 39 days after con- ception. The normal fetus was 82.10 mm long. Since its age was about 65 days, the dead fetus must have been dead about 26 days. The normal fetus weighed 82.10 gr.; the dead fetus 0.53 gr. The doe was in fair condition. She had no body fat, but the bone marrow was of a firm consistency. Her live weight of 79 pounds was better than average for the region (longleaf pine belt). _A blood sample collected from the animal hemolyzed and was unfit for serological study. 92 93 The majority of visibly gravid does was collected the first four months of pregnancy. If high mortality oc— curs in the three months prior to parturition, it would not have been evident. The ovaries of a 9.5-year-Old doe collected March 14, 1962, contained corpora lutea but none were visible even though a fetus becomes visible about 20 days after conception. It is unlikely that this doe bred as late as February 22, since most bucks in the area dropped their antlers by February 15. These corpora lutea probably represent early prenatal mortality or a recurrent estrus. I can find no reference to the persistence of corpora lutea in deer follow— ing prenatal death. Prenatal mortality is uncommon in deer. Sears (1955) found no evidence of abortion or resorption in 64 pregnant mule deer. Thomas (1962) found no signs of abnormal preg- nancies in 88 Texas whitetails. Teer (1960) found only one case of prenatal death in 220 pregnant Texas whitetails. Bischoff (1958) found 19% Of 64 pregnant California mule deer examined carrying abnormal fetuses. Teer (1959) described a dead fetus in a uterus con- taining a normal fetus in the Opposite horn. Bischoff (1958) reported three cases of does carrying twins in each of which one of the twins was dead and the other apparently normal. 94 a. Length Comparison Between Twin Fetuses There was no appreciable difference between the F-R or C-R measurements between twins in 37 sets of twin fetuses except in one case where one of the twins was dead and the other continued to develop normally. The greatest length difference between individuals of any set of normal twins was 12.0 mm. The average difference in length between all twins was 3.70 mm. Neither set Of Opposite sex twins tended to dominate in length. There was less discrepancy in length between twins Of early embryonic development. The average difference between eight sets Of twins under 50 days of age (less than 60 mm) was 0.82 mm. 29 sets of twins over 50 days of age differed on the average by 4.50 mm. Twins over 300 mm long did not show any greater difference in length between the two fetuses than did twins under 300 mm (Table 11). 95 .uCoEeHOmmofi QECHIC3OHO HO .QECHIomosonom HOCuHo REE CHs ¢.m NO.m mm.v mmmmum>¢ m.e m.mO O.ms O.m O.mm O.mm H.O m.mO 0.00 0.0H 0.0mH 0.0NH m.m 0.0e N.Om O.H O.emH O.mmH 0.0 0.00 0.00 0.0 0.0 0.0 O.m O.mmH O.mOH O.m O.NmH O.mmH m.O m.m O.m O.m 0.0AH O.HOH O.N 0.00H O.mmH m.O m.HH «.HH O.m 0.0mH O.HHH O.NH O.eOH 0.0NH O.e 0.00 O.em 0.0 0.0H 0.0H m.m m.mmH O.NOH m.e m.OmH O.eON O.m O.HHH O.esH O.H O.>H O.mH 0.0 O.HNN O.mHN m.O m.mON 0.00N 0.0 m.mmH m.mmH O.H O.Hm 0.0m O.m O.¢ON O.HON m.O m.OHN O.HHN m.m m.mON O.mHN O.H O.Nm O.mm O.m 0.00m O.mHm m.H m.OHN O.mHN m.OH m.OeN O.HmN O.m 0.0m 0.0m O.m 0.0mm O.mmm 0.0 O.mNN O.HmN O.m O.mmN O.mmN TOGO wwwsvwh , 00cm mwmsumh 00cm mmmsumh TOGO . mwmsuwh IuommHo no spaces nummmHo Ho Bumcmq nummmHo Ho auchH numOOHo mo summon Bunsen apogee numcmq Bumcmq xom xom ouHmommo mo mCHBB OOHmEOm CH39. mOHmZ CH39 C3OCxCD mo mCHsa .NomHI0omH .HomHmmemHz CH OOHOOHHOO Hoop CH3» mo muom 0m CH momsuom Coosuon COmHHmQEOU ecumCoH .HH OHQOB Figure 17. These two fetuses were taken from a 7.5-year-Old doe killed March 5, 1963. The top fetus was ap- parently alive and healthy up until the time of the doe's death. The second fetus probably died when about 39 days old and had been dead_in utero about 26 days. Copiah Wildlife Management Area Laboratory, Barlow, Mississippi, May 3, 1963. Photograph by W. H. Turcotte and the author. —.———.—_ g—_ 96 44.1Ub(1 CU>EmeUQ .U .2 .MUMJJOU 20.4” .00 >Jmle |_mo Oumeemum e>.e OO.m we.m Hm.e OO.¢ umeHO ecm mummy m.N moon mo 00¢ Ommuo>< me.N NN.N mm.H NH.N mm.H coHumH>mo enmecmum mm.e ¢O.N HN.m OO.m mm.e Hmumwwv woe mmmuw>¢ mm mm He mHH mm mNHm mHmsmm 0H 0H m 0 mm oouoououm mumow uHmm mmemeoH xoounnme couOcHucsm anmumO OHomHums .NOOHIOOOH .meuma HmmHmmHmmHs m>Hm Eonm OOHOOHHOO AHOOHO ©Cm OHO mums» m.Hv Homo OHmEOm uHsom mo momm Ommno>€ .NH OHQOB 101 limited. There, prior to scientific collecting, antlerless deer had been totally protected for 33 years. 85 adult does were removed from the area, nine in the spring Of 1960, 73 in January, 1961, and three in March, 1962. Because Of the relatively small number Of deer taken in 1960 and 1962, the data for all three years have been combined in analyzing the age class distribution (Table 14). The NoVember 1961, Merigold deer herd was estimated at 1800. The number Of bucks killed anually has never ex- ceeded 100. Usually it is less. Most Of the MerigOld members are trophy hunters. It is not uncommon for a hunter to pass up 10 legal bucks in a day's hunt. Catfish Point Hunting Club The Catfish Point Club controls 10,000 acres two miles south Of Merigold. The Mississippi Game and Fish Com— mission Operated the area as a refuge in the 1940's. The Com— mission 1ost its lease in 1951, and the landowners, Chicago Mill and Lumber Company, U.S. Gypsum Company, and Delta Pine and Land Company, turned the hunting rights over to a group Of Bolivar and Washington County sportsmen. The Club was in- corporated in 1952 and in November and December, 1952, the first year the area was hunted by the Catfish Club, 250 legal bucks were killed. Since that time the average kill has been about 145 legal bucks. 102 A full-time caretaker is employed. The poaching kill is negligible. Since it is known that some deer were poached on the area when it was a state refuge, total pro- tection for antlerless deer is dated from 1951. The NOvember, 1961 deer population was estimated at 1,396 (Noble, 1961b). Specimen collections were: spring, 1960, 14: NOvember, 1960, 54; NOvember, 1961, 42; and spring, 1962, three. All data were combined (Table 12). Huntington Point Hunting Club Huntington Point Club lands consist Of 18,000 acres south and adjacent to Catfish Point. A full-time caretaker is employed. Antlerless deer have been totally protected since 1953. The November, 1961, deer population was esti- mated at 1600. 41 adult does were taken from the area, nine in the spring of 1960 and 32 in November, 1962. Both sets Of data were combined to calculate average age. Ashbrook_;sland Hunting Club The Ashbrook deer herd is isolated on a 5000-acre island surrounded by the main channel and an Old channel Of the Mississippi River. The September, 1961, deer population was estimated at 800. A full—time caretaker is employed and lives on the island. Because Of inaccessibility except by airplane or 103 river-worthy boat, the illegal kill is negligible. Antler- less deer have been protected since 1952. .25 adult does were collected there on November 21, 1962. b. Collections in the Longleaf Pine Belt 22 adult does were collected from longleaf pine forests. These were taken from the refuges Of the Leaf River, Red Creek, WOlf River, and Chickasawhay Wildlife Management Areas. The number Of years each refuge had been protected varies from 10 tO 20, averaging 18. The Mississippi Game and Fish Commission employs fulltime personnel for pro- tection and management work. The only deer removed from these refuges are a few trapped each winter for restocking purposes. c. Comparison Of Individual Herds Apparently the life expectancy Of a doe in the wild does not exceed five years (Tables 12 and 13). Antlerless deer on Merigold have been protected for 33 years and yet the average age of 85 adult does from this herd was only 4.58 years. If the 1.5-year-Olds had been truly represented, the average age would be less. Since on Huntington Point, where complete protection has been in force for only seven years, the average Of adult does was 3.21 years, it seems that the 26 additional years of protection on Merigold has added only 1.37 years to the life expectancy Of adult does. 104 The average age Of 22 adult does from the longleaf belt was 4.59 years, and the animals have been protected about 18 years. There is only 0.01 years difference in the average age Of the longleaf does and Merigold does so the 15 additional years Of total protection at Merigold has had little effect on average longevity. The data indicate that a maximum average age for adult does was achieved after 10 to 15 years Of total pro- tection. Probably, the maximum average life was reached after 10 years Of total protection since few deer, because of severe tooth wear, live beyond this age in the wild (Table 13). Range conditions may influence average age but I do not have sufficient data from understocked ranges for com- parative purposes. d. Average Age in Statewide Sample 308 ages were determined from all adult female deer collected. With the exception of two confiscated illegal kills, all were collected from private club lands or state refuges where antlerless deer have received a minimum Of seven years total protection. Actually, except on a few club lands in Bolivar and Washington Counties in 1960 and 1961, antlerless deer have been protected by state law since 1905. However, one, two, or at most three game wardens to a county cannot provide total protection such as a relatively 105 small state refuge or an exclusive private club might pro- vide for their lands. Therefore, by total proteCtion, I re- fer tO a situation where few, if any, animals die except by natural causes. If age is normally distributed and the data (Table 13) represent a random sample Of adult female deer, the probability Of collecting an adult doe 5.5 years Old, or Older, in Mississippi is about 0.227. Actually, it is much less since the 1.5-year—Old animals are not truly repre- sented in the sample. Over 77% Of the statewide sample was less than 5.5 years Old. The average age was 3.92 years with a standard deviation of 1.43 years (Table 14). 106 Table 13. Age-class distribution Of 308 adult female deer collected in Mississippi, 1960-1962. Age Number in Percent in Accumulative (Years) Age-Class Age-Class Percent 1.5* 36* 11.4* 11.4 2.5 97 31.6 43.0 3.5 54 17.6 60.6 4.5 51 16.6 77.2 5.5 20 6.5 83.7 6.5 17 5.5 89.2 7.5 16 5.2 94.4 8.5 10 3.3 97.7 9.5 and Older 7 2.3 100.0 Average age = 3.92 years Standard deviation = 1.43 years *Since in many instances an attempt was made to shoot only does with fawns following, this age-class is not truly represented in the sample. 107 mm.N HN.N hm.H No.N Hm.H COHHMH>OG OHOOOOOO «H.O OO.m OO.O HO.O OO.O O.H OOONOO 004 ommuo>¢ OO.~ O~.~ OO.H «H.O OO.H OOHHOH>ON. Oumecmum O0.0 OO.N Hm.m O0.0 OO.O OOe.OOmHO>4 OH OH O O I O OO Omuomuoum. mumow HOHOB H.O N O.m m O.H O + Ocm O.O O.O H O.O H O.H O O.O O O.O H.O O O.e IH O.H H H.O O O.O m O.H O.O H O.~ H H.O O O.OH O O.O O.O m H.O O O.OH HH O.O O.OH O O.OH m H.OH O O.OH. OH O.OO Om O.e O.OO O O.OO O O.OH O O.OH OH O.OO HH O.m O.OO O O.OO OH O.OO Om O.HO Om O.HH OH O.~ IO.O H O.O H O.OH O O.OH OH O.O O O.H azmommm menses ezmommm Ommzsz ezmommm menses assumes Ommzsz assumes Ommspz Immense OHOO OOOHOzOH MOOOOOOO zoaozHazOm OOHOHOO OHOOHOmz mom IIII .HmmHmmHmmHS CH OOHOC msoHHm> EOHH Homo OHmEOH uHsOm mo mommmHO 00¢ ..OH OHQOB WEIGHTS OF MISSISSIPPI DOES Live-wieght records are relatively few in most states because hunters have a tendency tO clean their deer in the field. For that reason, the majority Of weights available in many states are hog-dressed weights recorded at road-side checking stations during the hunting season. Fairly accurate formulae are available for computing live weight from hog-dressed weight (Severinghaus, 1949; Park and Day, 1942). However, these formulae Obviously have limited application because Of diversified range conditions, because of the large number of subspecies Of Odocoileus in the nation, and because many states, through restocking pro- grams, have caused widespread hybridization between a number Of subspecies. Weights Of female deer are particularly scarce in the southern United States. Many Of the states Of this region (e.g. Mississippi, Louisiana, Alabama, Tennessee, and South Carolina) are just beginning to experiment with antlerless hunts on a limited basis. Furthermore, no relatively large sample Of female deer weights in spring is available for deer in the South so far as I know. Virtually all doe weights available were collected during the gun seasons in NOvember and December. 108 109 a. Factors Influencing Weight Weight varies with several factors, the most im— portant being sex, age, and local range quality. Gill (1956) has shown that weight varies according to locality which, in turn, is related to range condition. Female weights fluctu- ate as a result of fawning. This study provided an opportunity to collect ac- curate live weights on a relatively large sample of female deer. weight was recorded on 324 does; 292 animals 1.5 years of age and older, and 32 fawns. The fawns varied in age from four to nine months, but most were six months old. b. Doe Weights from the Batture Forest 293 does from Bolivar and Washington Counties (batture forest) were weighed. 108 adults were weighed in NOvember and December (Table 17) and 147 adults were weighed during January, February, March, and April (Table 18). Nine fawn weights were collected during the winter-spring period and 20 during November and December. Weights were separated into the November~December collection and the winter-spring collection for the follow- ing reason: Deer collected from the Bolivar and Washington County area in November and December represent animals fresh from lush summer browsing. Plenty Of high-quality summer browse is available well through October and into NOvember. Mast is normally plentiful through the remainder Of November 110 and into late December. January is characterized by winter conditions, and February and early March is the critical period for deer in this region. I felt that a significant difference could be demon- strated by separating winter-spring weights from NOvember- December weights. This, however, was not true (Table 15). The mean weight Of 152 adult does collected in NOvember and December was 108 pounds with a standard deviation Of 16 pounds. The average weight of 112 winter and spring col— lected does was 107 pounds with a standard deviation Of 14 pounds (Table 15). The difference between the two sample means is not statistically significant at the 1%.level (two- tailed test, calculated t = 0.639, tabled t for 262 degrees of freedom, 99% level = 2.326). Since January is the transition period between good and poor natural browse conditions, I eliminated January weights and compared the average weight of adult does in NOvember and December with the average weight in February, March and April. There was nO significant difference be- tween the two average weights. Nearly all the February, March and April does were in advance stages Of pregnancy. This could account for a four to 25 pound gain (Golley, 1957; Severinghaus and Cheatum, 1956). Consequently, in early spring a doe may lose 15 pounds of body fat due to inadequate diet, but this weight loss would be compensated for by the developing fetus 111 .mOCCOQ CHs OHH OO O OO O Baum: I .bmm HNucsoo OHHONOOOHV umouom poo30umm OCOHCD NO NO O ON NN scam: I .Amm HHOO OcHO OOOHOcoH OOH ON OH NOH NHH HHHOO ANOOOOO HO>HHOOO OCm COCOS. umouom onsuumm «ogmm nocmb HmOHuCCOU OOH mN OH 00H NmH .OOQ I .>Oz COumCchmk pCm Hm>HHomv umouom OHsHbmm BEOHH3 BSGHNS ZOHBEH>MQ BEUHH3 MNHm ZOHEOMHHOU ZOHUWM SDSHNQS EDSHZHE QMGQZflBm Zflmz figmzdm m0 mSHB III I .HOUHO OCm omm Ho mums» m.H moon HmmHmmHmmHS mo smucmHo3 O>HH OCH Co ConOH an mOHuwHumum .mH OHQOB 112 and embryonic structures. Presumably, therefore, adult does in the Bolivar and Washington County area do convert body weight into fawn weight between December and April. c. Doe weights from the Longleaf Pine Belt On January 11, 1966, I weighed 164 adult does, 1.5 years Old and Older, from the Leaf River Game Management Area in Perry County. The average live-weight Of these animals was 76 pounds. 22 adult and three fawn weights were taken in February and March (Table 18). The mean weight Of adults was 78 pounds with a standard deviation Of eight pounds. This is 29 pounds less than the mean weight Of spring adults from the batture forest. Mean spring weights from the batture forest and the longleaf pine belt when compared statistically indicated that the difference between the two means was highly signifi- cant at the 1% level (two-tailed test, calculated t = 9.490, tabled t at 99% level, 132 degrees Of freedom = 2.326). This undoubtedly reflects the higher fertility Of the batture forest soils. d. Weights by Age Class It appears (Tables 16, 17 and 18) that Mississippi does do not reach their maximum live weight until about 3.5 to 4.5 years Of age. They then gradually decline in weight through the remaining age classes, although the number Of 113 Table 16. Live weights* by age—class Of female deer col- lected in Bolivar County, Mississippi, in January, February, March and April, 1960-1962. Age Sample Mean Standard Minimum Maximum (Years) Size Weight Deviation Weight Weight 0.5 9 54 14 32 79 1.5 12 90 ll 73 106 2.5 16 109 15 80 138 3.5 24 113 12 81 129 4.5 24 112 ll 89 138 5.5 11 104 16 70 128 6.5 10 108 16 93 133 7.5 4 111 7 105 119 8.5 4 110 8 89 119 9.5 and Older 3 110 7 92 105 *In pounds. 114 Table 17. Live weights* by age-class Of female deer col- lected in Bolivar and Washington Counties, Mississippi, in November and December, 1960- 1962. Age Sample Mean Standard Minimum Maximum (Years) Size Weight Deviation Weight Weight 0.5 20 57 15 37 89 1.5 19 88 13 75 119 2.§ . 59 105 12 61 132 3.5 18 116 8 104 132 4.5 21 119 10 97 137 5.5 9 118 14 82 130 6.5 6 125 14 100 143 7.5 9 112 18 80 140 8.5 4 122 10 115 136 9.5 and Older 2 116 -l 116 117 *In pounds. Table 18. 115 Live weights* by age-class, of female deer col- lected in the longleaf pine belt Of Mississippi in February and March, 1960-1962. _i - :Sample Mean Standard Minimum Maximum (Years) Size Weight Deviation weight weight 0.5 3 52 22 is 77 1.5 1 57 2.5 6 75 8 65 85 3.5 5 82 6 78 92 4.5 4 80 6 72 86 5.5 6.5 1 88 7.5 2 78 -l 78 79 8.5 1 74 9.5 and Older 2 76 3 74 78 *In pounds. 116 weights available for ages 6.5 years and older is too small to justify far—reaching conclusions. Erickson §t__l. (1961) reported that Minnesota deer attain maximum weights between 4.5 and 6.5 years of age. Sweet and Wright (undated) found that maximum weight was reached by New Jersey Does at 4.5 years. Brown (1961) writing of black-tailed deer in Washington, stated that, " . . . does reach their maximum weight at about 3 to 4 years of age, then hold their own for a couple Of years or start to decline in weight." DEER MANAGEMENT IMPLICATIONS Some Of the findings Of this study can be applied to the management of Mississippi deer. a. Understanding the Mississippi Deer Herd The Mississippi deer herd has come a long way in the last 39 years. From a low Of a few hundred deer in 1929 (Leopold, 1929), Mississippi's deer population increased to an estimated 240,000 in 1967. Except for the 1,330,000 acres in 17 game management areas owned or leased and managed by the Mississippi Game and Fish Commission, U.S. Forest Service lands managed by the Commission, lands owned by the U.S. Corps Of Engineers, 80,000 acres owned by the U.S. Fish and Wildlife Service and a few privately owned tracts scattered over the state, all deer hunting lands in Mississippi are controlled by private interests, mostly well-organized clubs. There are 30.5 million acres Of land in Mississippi. 20 million acres could be classed as deer range. Less than two million acres are Open to public hunting. The remaining 18 million acres is posted, mostly by clubs, and is therefore, classed as private hunting. 117 118 Many deer hunters Of this state have seen the herds come from nothing to their present day abundance. They credit this increase in deer numbers to the total protection Of does and fawns. They are partially right: The total protection of antlerless deer is the best management known to establish a huntable deer population. Once large herds are developed, however, the total protection Of antlerless deer is the worst possible management. It is no more practical to leave all does on a well-stocked deer range than to retain all cows on a beef-cattle range. In either instance, over-use Of the range is sure tO be followed by disaster for the herd and its range. TOO many deer in an area results in a lowered repro- ductive rate, reduced fawn survival, poorly developed antlers, damage to natural vegetation, increased crop depre- dation, poor nutrition and, in some instances, to severe mortality (among all age classes but especially tO fawns) caused by parasites, disease, malnutrition or a combination Of these factors. One of the major Objectives of present—day deer management is to prevent herds from overcrowding their ranges. The only way to control deer numbers in a well- managed herd is through regular harvest Of does and fawns. The eventual need for antlerless-deer hunting in most herds results from years of "bucks only" hunting. Antlerless—deer hunting, however, is invariably a controversial issue. In 119 Mississippi, as in nearly every other part Of the country (for example, see Harrington, 1961; Brunette, 1957) it is difficult for the average hunter to accept antlerless deer hunting. b. The Time Of Year tO Hunt Antlerless Deer Traditionally Mississippi has two deer seasons an- nually. The first regular season Opens November 20 and, ac— cording tO county, may extend through December 1. The second season opens December 26 and again depending upon the county, may run through January 11. These seasons have been in ef- fect for many years. They were established for "bucks only" hunting. The recent need for the harvest Of antlerless deer on many Mississippi deer ranges has prompted the question, "when is the best time Of the year to harvest antlerless deer?" The findings Of this study indicate that the best time to hunt antlerless deer in north Mississippi is during the first week Of the second regular season (December 26 - January 1). In south Mississippi does and fawns should be taken in mid-January. The hunting of deer with dogs is legal and widespread in most Of Mississippi. In north Mississippi most fawns are born in July, and in south Mississippi most fawns appear in late August. By early NOvember, fawns are only three to four 120 months Old. These fawns are not as capable of eluding dogs as are fawns a month or two Older or fawns, Of any age, following the dam. The shooting Of antlerless deer in early NOvember be- fore the first regular deer season Opens (NOvember 20) re- sults in an unnecessary fawn mortality during the first regu- lar season. In 1961, the Mississippi Game Commission held an antlerless deer hunt on Catfish Point (Bolivar County) during NOvember 11-15 for the purpose Of collecting female deer for this study. I Observed during the following‘ November 20-29 regular deer season that an unusually large number Of fawns were captured and killed by hounds. This mortality in fawns can be reduced by delaying antlerless— deer hunting to the last week of December in north Missis— sippi and to mid-January in south Mississippi when fawns are four to six months Old and better able to care for them— selves if orphaned. It has been suggested that antlerless deer be taken in north Mississippi during a special season late in January. Deer killed in this region late in January are in poor flesh compared to those killed in December. In addition and far more important, 20-25% Of adult does in the region have visible fetuses in late January. The shooting Of visibly pregnant deer can accentuate the problems Of antlerless-deer hunting by turning many Sportsmen against “doe hunting“ in general. And finally, many bucks in north Mississippi Shed 121 their antlers in late December and early January. Mississippi hunters do not like to see adult, antlerless bucks mistakenly shot for does. Such occurrences generate public resentment against antlerless deer hunting. Late January antlerless deer hunting is recommended, however, for south Mississippi. Fawns are Old enough to care for themselves, browse is available well into late December, does there generally do not contain visible fetuses and bucks do not shed their antlers until February or early March. c. How to facilitate the Harvest of Bucks Whether still-hunting or dog-hunting, bucks are more easily killed during the height Of the rut than at any other time, yet on tOO many private clubs bucks are underharvested. If the seasons were set so that hunting was permitted during the height Of the rut, more bucks would be taken. Bucks are more wary and remain hidden during the daylight hours of the hunting season when hunting does not coincide with the rut. This is particularly true in the batture forest where many bucks remain hidden in Old lakes and sloughs during the day when the rut is not in progress. However, during the height Of the rut these bucks venture out in search Of does and thereby increase the chance Of being taken by a hunter. The ideal season to facilitate the harvest Of buCks in north Mississippi would be December 15-30; in south Mississippi, mid-January. 122 d. Recommended Hunting Seasons for Adequately Stocked and Under- stocked Deer Ranges On properly stocked or understocked ranges, however, deer should not be hunted during the height Of the breeding season. For north Mississippi, the season on such ranges should be Open to "bucks only" hunting NOvember 15 - December 1. When antlerless deer hunting is justified from a manage- ment standpoint, seasons for all deer may coincide with the rut. In south Mississippi, the season on above described ranges should be December 1 - 15. Earlier seasons (e.g., late October or early NOvember) even for "bucks only“ hunt- ing are out Of the question there due to heavy foliage and hot weather. e. Need for the Enforcement Of Laws Against Free-Ranging Dogs Mississippi has laws against free-ranging dogs, and state game wardens have the responsibility for enforcing these statutes. NO such enforcement actually exists, how- ever, except tO a very limited extent on some state game management areas. The people Of Mississippi will not toler- ate the Shooting Of free—ranging hounds, and nearly every deer—hound owner releases his dogs at least twice a month and many do not confine them at all. Consequently on many 123 deer ranges one can hear a "good deer race" almost any morn- ing in the year. Free-ranging dogs do little harm tO deer in the batture during the late fall, winter and early spring. But during the summer when does are heavy with fawns, hounds frequently pull down and kill deer. During seven years as Mississippi's deer biologist, I have seen dozens Of deer caught and killed by dogs. Many Of these were pregnant does killed in late June, July and August. The dog—law should be rigidly enforced in May, June, July and August. The State Game and Fish Commission should insist that dog owners pen their dogs during the period that does are heavy with fawn. f. NO shortage Of Breeding Bucks On Well—Stocked Ranges Deer numbers cannot be controlled by "bucks only" hunting. On club areas where 75%-80% or more Of the bucks killed each year are 1.5 Years Old, I found the frequency of pregnancy Of adult does to be over 90%. There was nO short- age Of breeding males in spite Of the heavy harvest Of legal bucks. APPENDIX APPENDIX HUNTING METHODS 110 deer were shot during this study under a special deer collecting permit. During 63 days Of collecting, 223 deer were fired upon, 110 were killed, 46 were definitely hit and escaped and 67 were assumed tO have been missed. The 30.06 was found tO be the best weapon for deer collecting. 52 (47.3%) Of the shot animals were taken with a 30.06 Remington WOOdmaster using 180 gr silvertip cartridges and open sights. Its tremendous knockdown power coupled with the ability Of a good marksman tO take long shots, proved the superiority Of this caliber over smaller guns. 21 (19.1%) Of the shot animals were killed with a 7.7 mm Japanese rifle using special loaded, 180 gr controlled expansion bullets and a 3.5 power scope. The 30.06 and the 7.7 Japanese are almost identical weapons. Very few "chance" shots were taken. Deer killed diurnally were largely ambushed from blinds constructed at food plots, watering holes or salt licks: The distance Of the shot was recorded on 58 animals. 32 (55.2%) were shot at a distancecaf 75 yards or less. The distance the deer ran after being shot was recorded on 60 animals, and 33 (55.0%) ran 30 yards or less. The anatomical 12.4 125 location of the fatal gunshot wound was recorded on 52 deer. 38 (73.1%) were shot in the thoracic region. A thoracic shot was usually a sure kill although the animal invariably ran a few yards before falling. A Spine shot drops the animal immediately but is difficult to make, and several animals were missed completely in attempting this shot. The eight deer Shot through the spine region fell in their tracks but all had to be dispatched with a second shot since a wound in the Spinal region always resulted, not in immediate death, but in total paralysis in the posterior end. LITERATURE CITED Albegglen, C. E. and A. Y. ROppel. 1959. 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Essays in Biology in honor Of H. M. Evans, Univ. Calif. Press, Berkeley and Los Angeles, 629-659. "IIIIIIIIIIIIII