and.” I. G .. .... L“— C THESIS M. ail-IQ 1: ... ..fl....:uh A SUQVEY OF THE FLY—IRODUCING SUBSTRATES IN AN UQBAN AREA AN ABSTRACT Submitted in partial fulfillment of the requirements for the degree of Master of Science in Michigan State University Department of Entomology East Lansing, michigan 1956 fl...» Approved ,/(: /;,, [AKY {/L/ ; ;(,/// "‘”Tt 1 ;7V/ “‘3 THESI? . .. u «Indy. «.11 3'»... 57‘;- O"\ '(A ‘Jé 1 MALCOLM MCREYNOLDS ' . ABSTRACT This study is a limited survey of flyeproducing sub— strates in five socioeconomic areas in and_near Lansing, Michigan, and of the species of flies produced. Four col- lections of adult flies were also made to obtain an esti- mate of the pOpulation. The five socioeconomic areas arbitrarily chosen were "Upper Residential", "Middle Residential", "Lower Residen- tial", "Business“, and "River”. With one exception, five blocks from each category were each surveyed twice during July and August, 1955. Samples of all substrates that con- tained larvae were collected and returned to the laboratory. Of the 198 positive samples collected, flies were reared and identified from 166. Garbage in cans or in trash was found to be respon— sible for the majority of positive samples,with dog manure next in the numbers of positive substrate samples. "Green" sewage sludge represented the largest volume of a substrate in a semi-permanent location. It seemed evident that the higher degree of sanita- tion, the fewer the Opportunities for flies to find satis- factory breeding areas. This generally followed the socio- economic levels. Exceptions were samples of dog manure that were prevalent in all the residential areas, and grass clippings which were more common in the High Residential locations. 2 QALCOLM MOREYNOLDS ABSTRACT Garbage appeared to represent the major substrate in the areas surveyed. Because of regular collection much of the garbage within cans had little opportunity to support larvae to maturity. Garbage cans in isolated locations, garbage thrown in tubs, barrels, etc., and an occasionally skipped route appeared to be more important as fly pro- ducers, especially in the Lower Residential areas. Although trash areas did not usually appear to be responsible for large numbers of flies, a large number of positive samples were taken from garbage mixed with trash, particularly in the Business and Lower Residential areas. The house fly, Musca domestica Linn., was more often taken from trash areas than from other locations and was rarely recovered from garbage in covered containers that were collected regularly. Late in the season "green" sew- age sludge was found to be producing house flies in large quantities. Phaenicia sericata (Meigen) appeared to be the pre- dominant species breeding in garbage cans. One collection of adult flies indicated a high popu- lation of blow flies. House flies entered the traps in ex- tremely small numbers in comparison to the numbers observed during the survey. The substrate survey was intended to be qualitative. However, with the possible exception of "green" sewage 5 MALCOLM McREYNOLDS ABSTRACT sludge, the amounts of semi-permanent substrates recorded seem to be less than would be necessary to produce the num- bers of blow flies trapped or the house flies observed. A SURVEY OF THE FLY-TROJUCISG S ) C: 33 (a t—S A} I1> F3 F3 [fl IN AN URBAN AREA by Malcolm McReynolds A .11”er n 1 .LAA utu; U Submitted in partial fulfillment of the requirements for the degree of Master of Science in Michigan State University Department of Entomology East Lansing, Michigan 1956 ACKNOWLEDGMENTS The author wishes to gratefully thank Professor R. Hutson and Associate Professor H. L. King for their constructive guidance in the selection, limitation, per- formance, and reporting of this study. A special debt of gratitude is expressed to Assist- ant Professor 3. L. Fischer for assistance in identifica- tion and for suggestions in organization. The excellent consultation and co-Operation of the jIngham County Health Department and eSpeciale Mr. Philip ”r \f. Shirley and Mr. G. J. Turney in selecting locations and 1J1 obtaining written permission for the survey was a great zaid.in performing the project. Grateful acknowledgment is also expressed to Assist- axit Professor G. Guyer for granting access to his personal crxpies of articles relating to the project, and to graduate staident W. Drew for the identification of the Anthomyiids. CHAPTER I. INTR II. HIS T III. AREAS A. B. C. D. IV. PRE A. B. C. D. ‘V. SUN“ LIIPERATURE TABLE CF CONTENTS ODUC TICN ORI 3A1 REVIEW . AND METHODS Areas Involved . . . . Substrate Survey . . . . . . . Species-Substrate—Area Relationship Survey of Adult Flies SEA TATION A‘ID DIS CUSSICN OF RESULTS Areas Involved . . . . . . . . . Substrate Survey . Species-Substrate-Area Relationship Survey of Adult Flies ANY AND CO‘JLDSI“ CITE . . . . . . 'fiav . . | (TABLE I. II. III. III. VI. LIST OF TABLES Total Number of Positive Substrates Collect- ed from Various Locations in Lansing, Michigan, during July and August, 1955 . Estimated Quantities (in Cubic Feet) of Various Semi-Permanent Breeding Substrates Observed in the Socioeconomic Categories Surveyed in Lansing, Michigan, during July and August, 1955 . . . . . . . . . . . . . Comparison of Incidence of Positive and Nega- tive Samples of Three Fly-Breeding Sub- strates Surveyed at Lansing, Nichigan, dur- ing July and August, 1955 . . . . . . . . . Frequency of Occurrence of Major Species of Flies in the Breeding Substrates Collected in Lansing, Michigan, in July and August, 1955 . . . . . . . . . . . . . . . . . Minor Species Recovered from Various Fly- Breeding Substrates Collected during a Sur- vey of Lansing, Michigan, in 1955 . . . . Samples of Fly-Breeding Substrates Collected in Lansing, Michigan, in 1955, Which Con- tained Two or More Species . . . . . . . . PAGE 15 l7 l9 25 26 27 TABLE VII. Volume of Adult Flies (Cubic Centimeters) Recovered from Traps in Five Socioeconomic Areas in Lansing, Michigan, in August, 1955 . . . . . . . . . . . . . . . . . . . . VIII. Dates in August, 1955, When Major Species of Adult Flies Were Trapped in Various Socio- economic Areas in Lansing, Michigan . . . . . IX. Dates in August, 1955, That Minor Species of Flies Were Collected as Adults in Lansing, hiiChigan O I O O O O O O O O O O O I O O O O 1. Relative Percentages of Various Types of Positive Fly-Producing Substrates. Lansing, fiichigan, 1955 . . . . . . . . . . . . . . PAGE 31 32 35 16 CHAPTER I INTRODUCTION An increasing resistance to DDT and some related in- secticides by certain of the filth-feeding flies has re- newed interest in studying the basic methods of control. One of the first considerations in initiating a fly control jprogram is to become familiar with the sources responsible .for producing these pests. West (1951) and Herms (1955) list many places where Ilarvae of the filth-feeding flies have been found. Both (emphasize the importance of sanitational control. Because tine conditions that are responsible for the major sources (if the fly pOpulation in a community may vary, a survey of tlie local habitats is often desirable. This study is a limited survey of an urban community ccuntaining residential, business, and industrial areas. 'Thea main.objectives were to determine the substrates that werwe supporting fly breeding in the areas selected and to iderrtify the species involved. An added incentive to work on tflnis problem was the author's specific interest in pest control service. CHAPTER II HI STC RI CAL REVI EN Many workers, including Hewitt (1310), Howard (1911), and Hall (1947), have listed numerous substrates where the filth—feeding flies have been observed to develop. Paine (1912) made a garbage-can survey of a tenement district in Boston. He found house flies and blow flies 'breeiing in garbage cans, under garbage cans, and in gar- lbage "houses". Blow flies ani house flies comprised over ‘35 percent of the larvae collected. Scudder (1949) suggested that flies are perhaps sec- cynd only to man himself in the contaminative transfer of knaman disease. In the same paper he emphasized the need fkar cultural methods of controlling flies. He pointed out tliat sanitation ani the general elimination of media suit- at>le for fly breeding and feeding must be practiced even when using a chemical having the effectiveness of DDT when it ‘was first released. Quarterman, Baker, and Jensen (1949), in their study of'.flyeproducing areas in the vicinity of Savannah, Georgia, fouxnd the city dump first in importance and the garbage can second. Sarc0phaga spp. were the major group that was found breeding in dog feces. 5 Lindsay and McBrayer (1950) believed that fly breed- ing in garbage cans and at a dump area was virtually elim- inated by accelerated collection and a sanitary land fill. They stated that larvae of Phaenicia spp. were capable of migrating from the garbage can to nearby soil when a twice- weekly collection was practiced. A three-times-per-week collection of garbage was practiced in their study in Georgia. Haines (1955) made larval surveys of two Georgia ‘towns of approximately 15,000 pOpulation. His results in- ciicated that Musca domestica Linn. were breeding extensive- ];y in animal pen litter and to a lesser extent in garbage zand fruits. Schoof, Mail, and Savage (1954) illustrated the ver- seaifility of !. domestica by recovering this species from They found Sarc0phaga spp. In eleven of thirteen substrates. tc> be the primary species recovered from dog stools. trieir*studies of three cities they found Phaenicia app. to ocuzur more often in contained garbage, while M. domestica was more prevalent in scattered garbage. Siverly and Schoof (1955), in a series of three pa- Pelfis based on larval surveys of Phoenix, Arizona, found 3. anuestica to infest nineteen of twenty-one substrates. Sarcxxphaga spp. were next in order, infesting thirteen of twentay~one substrates. Phaenicia sericata (Meigen) was fourth, infesting ten of the twenty-one substrates. Sar- c0phaga epp. were recovered more frequently from excrement and Phaenicia spp. were taken more often from garbage. Chicken, horse, cow, anl pig excrements gave high produc— tion potentials, whereas contained and scattered garbage were of less importance. in relating block environment to fly production, they observed that blocks with inadequate garbage collection, blocks with animal pens, and dump blocks had from two to thirty-seven times the potential for fly production that was present in other residential blocks where collection was aiequate. They recommended fly breed- ing substrate surveys as a basic approach to the fly prob- lem. One of the methods used in determining the pOpula- tions of adult flies has been the bait trap. Power and Melnick (1945) conducted surveys of New Haven, Connecticut, and found E. sericata represented 80 to 90 percent of all flies trapped. They had difficulty in luring E. domestica into the traps. In comparing the numbers of flies collected in the vicinity of four garbage dumps in Michigan and New York, Savage and Schoof (1955) found 2. sericata to represent 42 to 70 percent of the total adult collections. In additional surveys conducted in the northeast portions of the U. S., Schoof and Savage (1955) found 3. sericata and Phormia spp. to be the predominant species collected. ”Grid surveys" indicated E. domestica was more abundant than was illustrated by the collections. Phaenicia pallescens (Shannon) was not trapped at Grand Haven, Michi- gan, during 1949 and 1950, although it was present in 1948 at Muskegon. These two cities are approximately nine miles apart. Recent workers have recorded new data on the dis- persal habits of certain flies. Yates, Lindquist, and Butts (1952) recovered E. domestica at distances up to four miles from the release point. Their results also indicated that Phormia regina (Meigen) and Phaenicia spp. had the ability to disseminate to over four miles in forty-eight hours from the time of release. Schoof, Siverly, and Jensen (1952) reported that g. domestica dispersed rapidly in numbers to attractive areas within one mile from the point of release. Flies were col— lected at stations five miles from the point of release, although the numbers beyond the two-mile range were not large. They pointed out that more flies were trapped at locations containing fly attractants than at random sta- tions. Additional confirmation on the ability of E. regina to disseminate considerable distances was made by Schoof and Mail (1953), when they recovered specimens ten miles from the release point. The problem of overcoming the selectiveness intro— duced when bait traps are used in sampling an adult popula- tion of flies has been approached by standardizing a method for counting flies found on natural attractants. Scudder (1947) introduced a technique for sampling fly pOpulations by the use of a standard wooden grill placed over natural attractants. Later, in comparing the grill counts of adult flies with visual counts, Welch and Schoof (1953) found the visu- al fly density estimates by the same inspector to compare with the grill method by a 69 to 29 percent accuracy. CHAPTER III AREAS AND METHODS A. Areas Involved General Description. With three exceptions, all the blocks studied were within the city limits of Lansing, Michigan. The estimated pepulation of Lansing on January 1, 1955, was 100,500 as listed by Hoffman (1955). Two riv- ers, the Grand and the Red Cedar, enter the city from the west and east respectively, join in the south part of town, and exit from the northwest corner. Five socioeconomic areas were subjectively selected from within the city. The Ingham County Health Department aided in choosing these categories, which were based on the number of commercial establishments, general sanitation, and the proximity of the Grand River. The categories se— lected were "Upper Residential", "Middle Residential", "Lower Residential", ”Business", and "River". In 1955, twice-weekly garbage collection began on June 20 in all residential areas within the city. The usual twice-weekly garbage collections were normally started on July 15 and conducted until October 15. Above-average temperatures in June were responsible for the earlier beginning date in 1955. k. «a 5 1.4g . «MN-9L! militia, alt 41117.54 4 Mains.“ . Upper Residential. These areas were characterized by having a high degree of sanitation, a large number of garbage disposal units and by being definitely separated from commercial enterprises. Middle Residential. Sanitation in this grouping varied from good to fair. Host of the residents utilized covered cans for garbage disposal. Iets, such as dogs, were common; however, zoning regulations practically elim- inated other livestock. As expected, this category seemed to be the grouping most frequently found within the city. Lower Residential. Sanitation fluctuated from fair to poor. Garbage was more often scattered or placed in barrels, tubs, and other open containers. Dogs were prob— ably more numerous than in the other four areas. In sev- eral instances chickens were housed in the back yard. Business. Commercial establishments predominated with occasional living quarters present, usually on the second floor. Garbage collection in these areas usually consisted of making collections two or more times a week, depending upon the volume of garbage. Trash was removed by private contractors. River. Each block designated as a river area con- sistently bordered the Grand River. Commercial buildings and residential housing were also present. The city gar- bage disposal plant and a horse barn were incidental to this category. B. Substrate Survey The survey was conducted during the months of July and August, 1955. Weather information was obtained from the Daily Temperature, Degree Day and Precipitation Normals (1955) and the Local Climatological Data (1955), both pub— lished by the U. S. Department of Commerce, Weather Bureau. Average temperatures for the months of June, July, and Aug- ust were 0.5, 6.7, and 6.4 degrees F. above the respective thirty—year averages. Precipitation records for these months also indicated a respective increase of 0.44, 1.71, and 1.40 inches over the thirty-year averages. The survey began July 4 and continued through Septem- ber 2. One block from each of the five categories was sur- veyed each week. Because the Low Yesidential block for the first week was determined as unsuitable for this survey, a total of twenty-four different blocks were surveyed during the first five weeks. The survey was then repeated over the same areas during the second five-week period. Permission to conduct the survey was requested by contacting the occupants when practicable. It required from one-half to three hours to survey a block. Notations of the type of substrate, approximate amount, probable source, location, survey date, and specif- ic remarks were made in a field book. Because of the an— ticipated frequent occurrence of garbage containers, dog 10 manure, and piled grass clippings or weeds, a notation was made whenever one of these substrates was found not to con- tain fly larvae as well as for the positive samples. Empty garbage cans and small or scattered amounts of grass clip- pings were not included. C. Species-Substrate-Area Relationship The principle equipment used to collect the sub- strates consisted of a garden trowel, a largelxnwyhandled Spoon, and a sharpened circular spoon (seven—eighths inch in diameter). The latter was particularly useful for col- lecting various sizes of larvae from different areas of each substrate occurrence. This particular procedure was used in an attempt to obtain a better sample of the species present. A sample of each positive substrate, together with larvae, was placed in a one-fourth pint glass bottle in which a one-half inch layer of sand had been previously added to provide a place for pupation. All bottles were marked according to the corresponding fieldbook entry. Substrates that contained no larvae or pupae were examined but no samples were collected. A total of 198 positive samples were returned to the laboratory. fiixteen of these samples contained three or fewer larvae and pupae. Adult flies were reared from 166 11 samples. Rearing was performed in a constant-temperature room set for 80 degrees F. At one time the temperature of the rearing room rose above 95 degrees F., which may have been responsible for the loss of some larvae. Twice~week1y inspections were made to remove adult flies and to maintain the moisture content of the media. Although most of the flies emerged within one week after they were collected, the samples were examined regularly for an additional month. All reared specimens were killed in a calcium cyanide bottle, pinned, and labeled. Three labels were placed on each specimen. The first gave locality, date, and collector's name. The shape of the second label indicated the socioeconomic category, and its color represented the substrate. On the third label was the sample number that was placed on all specimens ex- cept those Sarc0phaga spp. reared from dog manure. Identification was completed during the fall and winter months. The Calliphoridae and most of the Muscidae were identified by the author and Mr. William Drew identi- fied the anthomyiids. D. Survey of Adult Flies Size of pepulation. In order to obtain a rough com- Parison of the fly pepulations present during the survey period, four collections for adult flies were conducted 12 from August 11 through August 51 in those blocks chosen for the substrate survey. As one block in the Lower Residen- tial classification had previously been rejected, only three collections were made in this category. Five bait-type traps measuring 18 x 15 x 11% inches were used. A band of half-inch hardware screen was placed around the base of each trap to help prevent loss of bait. After several unsuccessful attempts to make baits from those substrates found within the areas, a standard bait of fresh raw pork liver, sugar syrup, and milk was utilized throughout the nineteen collections. All traps were set on a twenty-four hour basis. Fresh bait was used with each setting. For comparative purposes, the volume of flies caught in each area and at each setting was recorded. To facilitate handling, the flies were chilled prior to making the volume measurement. Species of flies. A sample of one hundred flies was saved from each collection. All were saved if less than one hundred were collected. Although the flies for the sample were picked at random, no attempt was made to deter- mine the percentage of each species. These flies were identified as indicated in a previous section. Of the two labels placed on the specimens, one indicated the geOgraph- ical location, date, and collector; the other indicated the socioeconomic category. CHAPTER IV PRESENTATION AND DISCUSSION OF RFSULTS A. Areas Involved This survey is a limited study of selected locations ernxl should not be considered as necessarily representative <>f’ other cities of similar size or, for that matter, as a ccunrxlete cross section of the fly problem within the area. It; j.s believed that the survey results gave a fair picture of“ tflne locations studied. However, some other areas that are: excluded from this study may have a considerable influ- ence on the problem. Dump areas, located mainly outside of the' city limits, park and zoo areas, and rural communities adjamcent to the city are locations that should be consid- erecl in.the total problem. B. Substrate Survey Summary of all areas. All the substrates encoun— teretl were classified under the following twelve categories that zxre listed roughly in order of their importance by numbers of positive samples and the amount of substrate. 1. Garbage in containers 2. Dog manure 5. Under contained garbage 4 . Garbage in trash 14 5. Partly digested sewage sludge 6. Scattered garbage 7. Soil soaked with dishwater 8. Garbage-soaked sawdust 9. Grass and grass clippings 10. Dead animals 11. Chicken manure 12. Miscellaneous Table I combines these into six main categories. The caption, "Under contained garbage", refers to those larvae removed from under or around garbage cans. This classification was made in an attempt to determine if lar- ‘vae were escaping from garbage cans prior to the routine- <3ollection. It does not mean that garbage was under the (garbage can. Garbage, in various locations, produced the ilargest number of positive samples. Dog manure was second ill the number of positive samples. Figure 1 gives the rel— ative percentages of these positive samples. Records of those positive substrates that appeared to have some permanence are summarized in Table II. A1- though.the approximate amount of each substrate was record- ed, the periodic collection of garbage and trash made some 0f the figures unreliable as a basis for estimating a fly potential. 15 .eeme>H:m.mxoOHp nmsem 039*. .epmpquSm esp pod .mpomwms Ho GOHpmoOH musemeamem. mmH HH w mm 0 mm m# we proe om m I a I a m @ pe>Hm m: H H I H mH o ®H mmmeHmsm ..mm m I OH m OH H w Hmede IHmmm 30H mo I H HH . I m mm mm Hmecev IHmom mHeUHE Hm m d mH I H m w Hprer IHmmm emHm msomsmH mmsHQHHHo muscmn ewmppmo amass cw .mawo needs memo QH IHeomHz mmmmo moo pmpmppmom mwmppwo mmmp< Hmpoe mmmnnwu OHEosoonHoom mpwppmnsm III mmmH .emsesa nee sHse eszea .zaeHmoHs .mszsaq zH szHeaooa mmonas some naeomHHom maesmewmpm m>HeHmom so emmsez Haaoe H mng I” ' l6 Garbage In Garbage Cans 31-5 Under Garbage Cans’ 21.7 Dog Manure 19.2 0‘3 I“ ‘3) T ng m (4' a as can. 3 (DIS-I m UC) '? FIGURE 1 RELATIVE PERCENTAGES OF VARIOUS TYPES OF POSITIVE FLY-PRODUCING SUBSTRATES. LANSING, MICHIGAN, 1955 ‘"Under Garbage Cans" refers to the location of the larvae, not the substrate. 17 TABLE II ESTIMATED QUANTITIES (III CUBIC FEET) O‘F VARIOUS SE VI- PERMAE IENT BREEDING SUBSTRATES OBSERVE D III THE SOCIOECONOMIC CATEGORIES SURVEYED IN LANSING MICHIGAN, DURING JULY AND AUGUST, 1955 gagggg Location Substrate Ejggggged C97 Lower Residential Garbage in trash .2 212 Lower Residential Garbage 2.7 214 Lower Residential Scattered garbage .2 215 Lower Residential Dish water soil 2.7 25 River Garbage .2 C54 River Garbage .5 C82 River Sawdust 8.0 205 River Sewage sludge 190.0 C41 Business Garbage .2 C65 Business Garbage .1 C64 Business Sawdust .1 67 High Residential Grass clippings 5.7 C67 High Residential Grass clippings 5.0 -_____—::-1 km _‘-'_ 18 High Residential. In comparison with the other res- idential categories in Tables I and II, this grouping had fewer fly-producing areas. Garbage disposal units were al- so more common. Dog manure was responsible for the largest number of positive samples. As shown in Table III, the number of samples of dog manure that did not contain fly larvae was also highest in this category. Although there were onlyfour'times when grass clippings yielded fly lar- vae, the fact that there were more piles of grass clippings in this category provided a slightly higher potential for this substrate. Midile Residential. Garbage in cans was the major source of positive substrates. Routine garbage disposal was designed to destroy most of these infestations before they began to migrate from the cans. The number of posi— tive samples collected from under or arouni the sites of garbage cans indicated some larvae were escaping before collection. Ten of the twenty—eight samples collected from these locations were taken from one block having a break in the routine collections. The remainder were scattered throughout the other blocks surveyed. Three ways of ex- plaining their presence are: 1. They escaped from the cans prior to routine col- lection. 19 TABLE III COMPARISON OF INCIDENCE OF IOSITIVE AND NEGATIVE S MPLES OF THREE FLY—BREEDING SUBSTRATES SURVEYED AT LANSING, MICHIGAN, DURING JULY AND AUGUST, 1955 Substrate ; n . t . . arbage in Dog Grass r S o co omic Ar 8 U . . . i 0C1 e n e S Containers Manure Clippings‘ g Pos. Neg. Pos. Neg. Pos. Neg. High Residential 6 59 15 25 4 8 Middle Residential 25 100 ll 15 1 2 Low Residential“ 8 28 10 21 - - Business 19 46 - 2 1 1 River 6 10 4 5 - 5 Total 62 225 58 64 6 14 —_- — ‘Includes only the piled grass and weeds that seemed capable of supporting fly larvae. HTwo fewer blocks were surveyed in this category. 2O 2. Each block was occasionally missed during regu- lar collections. 5. Larvae escaped from the cans before twice-weekly collections were begun. Which of these occurred is beyond the sc0pe of this study; however, observations indicate that the first is the least probable. As there was no constant pattern of larvae found under the garbage cans, it appearei that twice-weekly col- lections were adequate when all garbage was collected on this schedule. Dog manure yielded almost as many positive samples as in the High Residential area, although the total number of occurrences was fewer. Low Residential. The number of samples collected is misleading as there were two fewer blocks surveyed in this category than in the other four. The number of residences per block was also fewer and more samples were obtained from trash areas and scattered garbage. Garbage and trash were more often mixed and occasionally garbage was buried or fed to chickens. Although the number of samples was smaller, they frequently represented larger amounts of sub- strate. In a few instances garbage was found piled in loca- tions where it would probably remain until decomposed. As shown in Table III the total number of samples of dog ma- nure found was almost as high as the number found in the 21 High Residential category. Besides the two fewer blocks surveyed in the Low Residential category, tall weeds and trash areas made it more difficult to locate stools. Business. Garbage in cans and near trash areas represented the majority of the samples in this group. Al- though some contained garbage from the commercial buildings was producing maggots, the waste material from living units in these blocks was responsible for breeding more flies. An accumulation of food materials, in the bottom of or un- der trash containers and around piles of trash, accounted for the relatively large number of samples collected from near commercial districts. gizgg. Although an occasional dead fish was found: floating in the river or in the shallow waters at its edge, sixteen of the nineteen positive samples were taken from the usual waste products of the residential and commercial areas located in those blocks bordering the river. A horse barn, incidental to this area, was examined twice during the survey. Numerous old pupal cases were present in one location where manure was loaded into a truck. However, this area was too dry to support larval deveIOpment at the time it was surveyed. It was observed that the stable was attracting large numbers of flies, per— haps largely house flies. Numerous larvae were recovered from the "green" sewage sludge during the second survey of the river area 22 adjacent to the garbage disposal plant. Although it is not known how long sludge was handled in this manner, the vol- ume on September 2 was large,as shown in Table II. C. Species-Substrate-Area Relationship Substrates containing one species. Table IV com- pares the frequency of occurrence of the major species in the principal substrates. 3. sericata was present in the samples collected more often than any other species. Six of the eight substrates listed in Table IV were infested by 2. sericata. Sarc0phaga 522. were next in the total number of oc- currences and were limited almost entirely to dog manure. Schoof, Mail, and Savage (1954) also found Sarc0phaga §pp. to be the main species found in dOg stools. As a sample was usually from one stool, this may not have represented a large volume of substrate. Both 3. domestica and E. sericata seemed capable of developing in a relatively large number of substrates. M. figmestica was in six of the eight substrates plus one mis- cellaneous sample. In comparison with the total numbers of occurrences of each, 3. domestica seemed more versatile. Garbage, in various locations, was utilized for lar- val develOpment by all of the twelve species shown in Table 11- Under the conditions found in the survey 2. sericata 23 .mpmsprSm pom .mm>uma mo coaumooa mmponUQHm mm o: no # U\ (M U\ mHH C\ CH (M H I I ¢ r4 r4 CU Hmpoa .mmw mwmnmoopmm mmvfimmnaoopmm w.ncaqv a: msmnpwoamo mhxosopm 16.6ama maopmooSmH mm s O hqwaammv msmHSQmpm mdwomdfi hamawmhw mfiaflsflmmw mswomdé .acmm moflpmeOU moms: mmvflomzz A.Q.mvmm>onlmmnnmu weaponm0ponm hammamsv maHMmp washonm bummamsv mpmoasmm mfioficomnm snowmose manpmsaaa «assess mmeanonmaaamo Hmpoe adomsma Iamomwé mmsflmmfifio smxowno moo mmmpo madam: mwmnumm Umpmppmom *msmo mdmo mmmhd QmmHB HmfiGD CH dam Swmhe mwmnpmm mumppmnsm moflommm mmeH mHm.V mcoomosom mpmnmd .AsomHm2vaHmmp wasposm mac .povc: mmuHosmsspe .A. vonv mEopmoode my a o x moo x x méo n.60MnV mEOmeOSoH mphnmo x x 0H0 A.Q.mv mm>osuomupmu mHspOQQOpopm x Hm .meG: mmeestSLB Nd n.o.mvom>ncuomppmp mHEpO£MOpopm .ncmeo2V msHmmn mHseonM x om AsomHm2V msHMmp mmsponm x 5H AsmmHo2v wsHMmp mHsuonw x m uwmnnmo dousuaoo .ecas wmmmHmsv mponpo mOHpmmsow mumOHuom .oz onswm mows2 mHoHsmwnm mam opmnpmnsm I! .mmma zH .zaonoHs .wszzaH moHommw H> mqmde mmHummm mmos mo oee amzHeezoo mOHmR .H oceomsaoo mseaeemmpm ozHommmmussa so mmamsam 28 A.QGHHV mammpHono m2x080pm .AdeHmmv msmHsnmpm .w .ncwHammV mHHHsHmmm wsHom52 .ncmmHm2v manmSHHH mHHHosg .mm mwmnmoopmm ..mm macaw .mm mmmanopmMI..mm m amH m .mm mwmngooumm ..mm mHssmm .mm mMmflQMopmw ..mm mHssmm .MMm mwmnmoommw .mm mwso22m ..mm mwmQMOopmm .A.@somv mmsnoaHHo mhsonm .mmm mmmnmoopmm .mm mHmsonps¢ 2.6somv weapoHHHo mMEoHNm .povsd mmHHHmsOHpmepw ..mm mopopmwm x x de x x . moo ommnnmm Voonoppmom mom mom mom dom x dwo mm x m2 muscm2 woo UHN mam mHN mHm HHN mom n.psooV mmmpd amass NNNX NNXXN .aGMH wnomam2~ mnmnpo moHpmosoc mponpmm .oz «Hgsmm momma mHoHsownm 6cm mpmnpmnsw mOHoomm nauseapuooV H> mqm mqm<9 50 last two dates were respectively 8.4zunll2J+degrees F.below the average for August, 195 . The large numbers obtained on August 17, as shown in Table VII, seemed to be more rep- resentative of the actual situation. Species of flies. No attempt was made to determine the percent of each species. Table VIII does show that E. sericata was present at each collection in all areas. There were only two collections in which E. regime was not represented. Table IX lists the minor species trapped and the reSpective collection dates. 51 TABLE VII VOLUME OF ADULT FLIES CUBIC CENTIMETERS) RECOVERE FROM TRAYS IN FIVE SOCIOECONCNIC AREAS IN LANSING, MICHIGAN, IN AUGUST, 1955 :— -: Date Residential . . Collected High Middle Low Bus1ness River Aug. 11 --‘ 220 --*' —-‘ 20 Aug. 17 440 650 1500 650 200 Aug. 25 50 15 120 70 110 Aug. 51 50 240 150 --‘ 5O *Less than 10 cc. *‘No collection. 52 x x M x x x x x .ndHA MOHpmosoo womsz mmvHoms2 x x x x x x x x x x N N x x x x x AGmMHm2V mcHMon mHsnonm x x x x x x x x x x x x x x x N x x AcmmHo2V wpmoHnmm «HUHQmmnm x M x x N x x x A.wom2v mHvaHamxfinomo mHOHsomnm x x x x x N .N x x x x .x AsmemEV manmsHHH mHHHofiq M x x x x x x x Asome2v sanm>HHw wHHHosHomsm mmeanoseHHHwo Hm mm 5H HH Hm mm mH HH Hm mm 2H Hm mm 5H HH Hm mm NH HH seq oHeeHs swam nm>Hm mwmsHmsm moHoon Hmesovamm mpwa 6cm QOHpmooq oHsosoomOHoom z 2H ommmams msaa mqus gamma so mmHommm moeas zmme .mmmH .ampus< 2H amass HHH> mqm