WI } x WWI“ ‘ x ‘ 1 WWWHUIHIWIIH WW“ we II III II IIII III III IIII III II IIIIII II IIIIIIII IIIII 136 A!“ #131 St?” Mandi” This is to certify that the thesis entitled Food Preferences Of The White-Tailed Deer ( ODOCOILEUS VIRGINIANUS BOREALIS ) IN MICHIGAN presented by KHUSHAL HABIBI _ has been accepted towards fulfillment of the requirements for Master of SCiencidegreein Fisheries & Wildlife éaflflm Major professor Date 8-8-79 0-7639 ”W'MON I} f l '5’ I“ J— 22:7 Va 6 my 5 A: manta? -_ . "I x". ' »‘\ P‘s unnu:b d. (Ni/€237 , 338T4151 1998 ' FOOD PREFEPENCES OF TILE WHITE-TAILED DEER (ODOCOILEUS VIRGINIANUS BOREALIS) IN MICHIGAN By Khushal Habibi A THESIS Submitted to Michigan State University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Department of Fisheries and Wildlife 1979 ABSTRACT FOOD PREFERENCES or THE WHITE-TAILED DEER (ODOCOILEUS VIRGINIANUS EOREALIS) """"“1fi'fii§fii§ifi'""“""' BY Khushal Habibi A study of food preferences of the white-tailed deer was conducted in three geographic regions in Michigan during the spring of 1979. Food habits of deer were found to vary considerably between the ecological regions. Plants which were favored in one area often were neglected in another area where more palatable species were available. Preference ratings were not correlated with the abundance of particular species found in.each locality. Common elderberry. staghorn sumac. juneberries. red-osier dogwood, silky dogwood.and gray dogwood were preferred region-wide in the southern part of the state. The dogwoods and juneberries showed the heaviest browsing in this area. In the north-central part of the lower peninsula nannyberry. quaking aspen, silky dogwood. red maple. American elm, sweetfern, willows and red and white oak were selected by deer while gray dogwood, red maple, American elm and sweetfern were utilized in large quantities. Preferred foods in the western part of the upper peninsula were red maple. Khushal Habibi juneberries. American elm, red raspberry and a honeysuckle species. At this location. red maple. American elm. juneberries and balsam fir constituted the main bulk of the deer's diet. American yew and white cedar. generally accepted to be highly-preferred white-tailed deer forages in the northeastern temperate forests were not encountered on the study plots. Their complete absence from the range possibly indicates that these species have been eliminated or drastically reduced from mainland habitats due to overbrowsing. Common elderberry seemed to be generally overbrowsed and possibly becoming much reduced by abundance. It was present only in small numbers over most of the range. Nannyberry and staghorn sumac were also utilized extensively where they occurred. Overdutilization of preferred deer forages provides further evidence of over abundant deer throughout the state. Deer are too abundant for the present range to support. Widespread and intensive cuttings of forests, woodlots and small-holdings is called for to regenerate vegetative habitats. This can only be successful. however, where deer numbers are adequately reduced. TABLE OF CONTENTS LIST OF TABLES . . . . . . . . . . . LIST OF FIGURES . . . . . . . . . . . INTRODUCTION . . . . . . . . . Objectives . . . . . . . . . Study Areas . . . . . . . . . . Climate . . . . . . . . . . Soils . . . . . . . . . . . Vegetation . . . . . . . . . . . METHODS Calculation of Preferred and Principal Values Range Condition . . . . . . . . . Vegetation Classification . . . . . . RESULTS . . . . . . . . . . . Food Preferences . . . . . . . . CONCLUSIONS . . . . . . . . . . . Regional Variations in Forage Preferences . Plant Species Endangered by Over-Abundant Deer Range Condition . . . . . . . . . S UIVII‘JIARY a c c o o c c o c c o o 0 LITERATURE CITED 0 O O O O O O O O 0 APPENDIX . . . . . . . . . . . . ii Page iii iv VU’IU‘NN l-' Table \1) LIST OF TABLES Percentages of vegetation available and eaten by the white-tailed deer by forage classes based on 200 samples in each locality. Food preferences of the white-tailed deer at Rose Lake upland sites, Clinton County, Michigan, winter 1979 Food preferences of the white-tailed deer, Rose Lake lowlands (Corey Swamp), Clinton County, Michigan, winter 1979 Food preferences of the white tailed deer, Houghton Lake Wildlife Research Station, Roscommon County, Michigan, winter 1979 Food preferences of the white-tailed deer, Higgins Lake upland sites, Roscommon County, Michigan, winter 1979 Food preferences of the white-tailed deer, Cusino Wildlife Research Station, Alger County, Michigan, winter 1979 Variation in food preference rating of some preferred species at the Lower and Upper Peninsula study sites, Michigan, winter 1979 Percentage of forage availability and utilization for all preferred browse plant species of the white-tailed deer, Michigan, winter of 1979 iii Page 17 18 20 23 25 27 3o 34 LIST OF FIGURES Figure Page 1. Map of Michigan showing the relative location of the study areas 4 2. Mean annual temperatures since 1969 and monthly precipitation levels for 1978 at the study sites 6 3. Vegetation sketch of the Rose Lake Wildlife Research Station study area showing the major plant communities 8 4. Vegetation sketch of the study area near Houghton Lake Wildlife Research station showing the major plant communities 10 5. Vegetation sketch of the fenced enclosure at Cusino Wildlife Research Station indicating the major plant communities 11 6. A picture of the Rose Lake upland woodlot 21 7. A picture of a section of Corey Swamp showing thick shrubby vegetation 21 8. A picture showing white-cedar browse line on a private owned plot at Rose Lake 35 iv INTRODUCTION Those foods which are proportionately more frequent in the diet of an animal population than in the available habitat may be termed preferred foods. Species which are less abundant among the total foods consumed than in the available forage are known as neglected (or totally avoided) foods. Those foods which are eaten exactly to the extent to which they are available in the habitat, are neither preferred nor neglected and are considered neutral with regard to the feeding preferences of the consuming animal (Petrides 1975). Regardless of preference, principal foods are here regarded as those which constitute the main bulk of the diet. Food preference studies have important ecological significance. As preferred species tend to be eaten heavily. they are depleted first and may be referred to as 'decreaser' species in the habitat. The neglected species in turn, are "increasers" where grazing pressure is not severe. By measuring the available vegetation and the amounts consumed, the degree of utilization for particular species can be calculated. By determining the severity and persistence of forage species utilization, habitat trends toward improvement or degradation becomes evident. The suitability of the range for a given herbivore population and the range capacity to withstand use can be evaluated. In this study, winter diets and browse preferences were reviewed for the northern woodland white-tailed deer (Odocoileus virginianus borealis) in Michigan. Evaluation was made of deer winter browsing habits at five sites in three widely-separated Michigan localities. The investigation was undertaken to establish guidelines to possible further research. Objectives The effort was made to determine in each area which forage species are preferred above others and which are important in the deer's diet in terms of bulk composition. The investigation was made to see to what extent browse use and preference values vary by geographic regions. Comparisions also were made for different sites within regions. Still further, since calculation for abundance and utilization can be made either by twig weights or’numbers, the attempt was made to see which method was more suitable. In this study, browse preference ratings were calculated only for winter. This season is when food resources tend to limit animal survival. my 1.__reas For a number of decades, the Michigan Department of Natural Resources (DNR) and its predecessor agencies have recognized three administrative regions which have distinctive ecological and land use characteristics. A.wildlife research station of the DNR is located in each region. In the farmlands of southern Michigan, the Rose Lake Wildlife Research Station comprises 1350 ha. of relatively infertile lands situated astride the Clinton-Shiawassee county line (Figure l). The original farms were abandoned during the great economic depression of the 1930's and were assigned to the DNR. A portion of muckland, known locally as Corey Swamp, also occurs on the Rose Lake Station. Two study sites were located on both upland and muck soil types in sections 13, 14, 23 and 2“ of TSN, RlW. ._ The Houghton Lake Wildlife Research Station has a central location in the state's lower peninsula (Figure 1). Situated in Roscommon county, partly along the Muskegon river, the area is almost 90 sq. km. in size. Observations were confined to lowland deer habitats in the northawestern part (sections 1. 2. 6. 11 and 12 T22N, RAW) and alo two upland wooded areas on rolling hills in an adjacent township (sections 10 and 15 T24N, R3W). The Cusino Wildlife Research Station in Alger County of the Upper Peninsula includes a 256 ha. fenced area (sections 19 and 30 Th6N, R17W) in which, as on the above areas, deer food habits and forage utilization were appraised. £70 zj?5? LAKE SUPERIOR:D 2: Scale 0“ g; m, E O 35 70Km I an E5 ~ ii :3 h: H a: c) H s: [:1 55 .4 I Rose Lake (and Corey Swamp Figure 1. Map of Michigan showing the relative locations of the study areas. Climate The climate of Michigan is generally cold-temperate. Rainfall is sufficient during the April-October warm months (Seeley 1917). The study sites lay between #6'5' and 47'7' north latitude with some differences in climate between the regions (Figures 2a and 2b). Mean annual temperatures and rainfall equivalents recorded during the past ten years are 8.5'C and 761 mm. respectively for the East Lansing Station (15 km. west of Rose Lake), 5.9°C and 706 mm. at Houghton Lake and 5.2‘c and 922 mm. at Chatham (32 km. west of Cusino). High levels of precipitation, much of it in the form of snow, results in long winters in most parts of the deer range. Snow accumulates to a depth of 1 m. during the coldest months forcing deer to restrict their movements within yarding areas and resulting in intraspecific competition for forage (Severinghaus and Cheatum 1969, Verme and Ozoga 1971). Sails. Rose Lake: The soils of the upland sites belong to the Boyer series and consist of well to moderately-drained loamy sands and loams on gently-sloping to steep moraines. The Corey Swamp soils are Houghton muck to a depth of 150 cm. or more. The surface layer is black and well-decomposed to a depth of 25 cm. (Pregitzer 1978). 10- AFast Lansing 0 ’v,"”-----\\\ ,’f \‘\,o""\\ a) \’ \\\.4 "”‘\ g Houghton Lake ‘~\ +> \ /\ g . m 5‘ 2' Chatham 0) +3 r-l m 5 g 0 I I I I fl I I l g ex c: sq m: cw d- vx \o b— cn \o c- b— c- c- c. c— c. c- b- o O\ ox Ox 0\ Ox 0\ Ox 0\ ox ox E H H H H H H H r-l H H Figure 2 a 2 O '1 .5 5 c .3 200 ‘ Chatham +1 :3 OH O ‘ e: 15 0 Houghton 0 s. 100 - / 9. >3 :2 ~ ~~ *E 50‘ “7’" 0 g O \/ I I I I I I I l U l .52 .e .4 o H o >, . +> . . g .o a n >. g .4 u) a. -P > <3 o m a. w s s o 0 <3 o P: In 5.: 4: 2 h *3 <2 U) 0 2 C: Figure 2 b Mean annual temperatures since 1969 and monthly precipitation (rainfall equivalents) levels for 1978 at the study sites. Based on climatic data of National Oceanic and Atmospheric Administration, U.S. Department of Commerce. Houghton Lake: Most of the study area is lowland, with Rifle peat, a dark-brown, coarse soil rich in particulate matter. Surface soils are dark or gray or nearly black due to high organic matter (Veatch et a1. 1924). Often adjacent, and developing under poor drainage conditions, are heavier Bergland mineral clay loams and Newton loamy sands. Cusino: The soils at this location are basically sandy, highly acidic and low in fertility. Surface soils are gray with a characteristic subsoil or hardpan or rust-colored or brownish sand. Dark-brown Carbondale muck often extends to a depth of 30 to 60 cm. and is high in organic matter. Vegetation Rose Lake: Ranging from farmlands to forest, the area has a complex array of native communities. Over 90 species of trees, shrubs and herbs are known to occur. In upland woodlots, the oak-hickory (Quercus-gggyg) association predominates (Figure 3). Gray dogwood (Cornus racemosa), juneberry (Amelanchier spp.), rose (Egg; spp.), red raspberry (Rgpggliggggg) , and blackberry (Rgpgg allegheniensis) occur in the understory. Between the forest stands are many abandonedcfld fields and open grassy knolls. Species such as Scotch pine (mi sylvestris) and autumn olive (Elggagnu§_umbgl;ata), not native to Michigan, have been planted in small stands. Corey Swamp, a portion of which extends into the Rose Lake Station, is mainly covered with shrubby vegetation. Silky dogwood (Cornus amomum), 8 Figure 3. Vegetation sketch of the Rose Lake Wildlife Research Station study area showing the major plant communities. + H”.*.+.‘-'.*-.-- ' :fi In“ av mm as - iti; IIYIYIVID C. -ag%°oo°c§" .3 . I, 9.0 I (g at can “'5. {llrl'lttlgoo 06.010030906 m yg’iy’ ”we; 9. E'Gfgcvcflguvuw I“ ;~. ”pl! & 1 _ . .0 QHHHHHHI ”“31. iii: if“ . .- Siffuuuuuuw “4.5. in g1 pen “I": ygy! ' “9:” 11:” . GI ., it ‘ gang 2; 1‘! Qua: In, HI. £1 83894: r66) 9: do :2 twig I” - ' ' 995mm :00 ”-54 wHHii-LEO o ' 73‘“: (gm 3 :H.~"-’ . o - ouwwue a? um-z} _.-_‘.'.Cla?3h Roadgvoea‘flcfihfii . ' 2: . ,1 2"" u talc—.1 0c:- - . 2' unfié) 2,0" ' £3". I” : W :1 ‘II'; - .. I 32': 9,23? ‘4” v I 0 Hit-31 . g; I‘M: m1”. ~11tIHHHHI _ 32'“.vaku . . figmwmwgggu #1 .-'~€JQ.£- HHH . ~)- :..:.::..-_ .-.- .'i.: at). 233* v *Intjgcicé§%%%a “A - - W ‘5 aces. awe. {56 .: IE")! 635.: .-._--. . 'f 5:331! .7. . _ .. .z‘y LEGEND 4M5}? Hardwoods: oak-hickory "HIE!” Swamp: dogwoods and willows Hm . . out Cultivation: corn and wheat Openings : grass ”a; Pine plantations: Scotch pine red-osier dogwood (Cornus sto;onifera), gray dogwood and willow (Salix spp.) are common. Cattail (Typha latifolia) marshes occur in depressions. Houghton Lake: The vegetation here ranges from hardwood stands and coniferous woods (Figure 4) to willow and cattail marshes and to leatherleaf (Chamaedaphne calyculata) wetpans. On the study site, the upper story is composed variously of white pine (gipgglgtrobus), jack pine (Eggs banksiana), red pine (Li-{mg resinoga), white spruce (Piggg,glggg§) and balsam fir (Abig§_bal§amea). The ground cover is dominated by blueberry (Vaccinium spp.), leatherleaf and sweetfern (Comptonia peregrine). . At the nearby Higgins Lake study area, mature oak-maple (Quercus-Aggg) stands frequently contain juneberry and American elm (91mg; americana) in the understory. White pine and balsam fir also are intermixed among the deciduous species. Cusino: The vegetation at this northern location is predominantely white birch-red maple but with white pine, white spruce and balsam fir as common conifers. Sprouts of red maple (A22£.£2222E)c American elm and juneberry farm the bulk of understory vegetation. Although not extensive, a swampy portion of the fenced area is dominated by willows (Figure 5). Figure A. 10 Vegetation sketch of the study area near Houghton Lake Wildlife Research Station showing the major plant communities. Od g_u as O $.66 a#% + h 99’ .cG 0(3) a. Q ‘7 *iihw i av“)- -. ye Vs IS IQEKE It “Ishtar" * a ‘%‘** v .p s": " &+90&+9 go of ‘s *kxk: V? 0‘ I. n‘w *~**k‘~* 1*: K *& I‘Iktg'fl‘ * K a( &“ k m n LEGEND Hardwoods: Aspen and white-ash Conifers: Jack pine and balsam fir Marshes: willows and cattails Openings: blueberries and grass Scale 0 50 O 1000 m. 11 LEGEND (3’0 Hardwoods :birch-maple ‘1? Conifers: Jack pine white pine, balsam fir and white spruce yr w ’5‘!“ Swamp: willows n... ,. .. I ,;-:- Openings: blueberries ' and grass .‘i‘i '.-..-.._, _~—)_. fig ‘\_ I“ -. "o t . a ”§§”§'§O§ In" 4. (jg? 0\ m I Ht 1 , (.3. a): )0 (3 § .. Q’; 51.33933?) 3 —m , t . .‘z , .- . .I.‘ 121.}... - . 1 . 2.. ': {2:25. :‘_.‘ ' ’c =--"-. 7:- Scale "s'e to (.085 6.: 6g =— 5: 6.3:‘9945‘3’a' - (300 "1‘12? 3%; 1+ 3;} . “-6) ’12}? (ac-$32) QETG‘C: A. _-. \'-‘§’ka . o~$§53 O 200 00 m. x Q (9‘670 * 22‘0’9 . ‘:c)£ ' Vélf'O' * ‘)* c p ) *E)‘ ‘9‘ 00.09 .48" (”c- 00.1: e) 4049*“ 2? Q1298 619:) $29 3:1. .- 10441292; g.) £ “7 c" ('1 9* ”OS :9 51“ Q7099§9L§D§7§s “:32'539. 053 ' 36' Figure 5. Vegetation sketch of the fenced enclosure at Cusino Wildlife Research Station indicating the major plant commmities. METHODS Vegetation Survey In each location, preliminary observations were made to determine the presence of deer tracks, droppings and browsed twigs. Areas of evident heavy use by deer were selected for further study. Only the utilization of browse was taken into consideration. The winter utilization of herbaceous plants by deer was not investigated but was believed to be slight. A11 observations were made during April and May 1979. Browse clippings were made from 1000 circular plots each with one meter radius. 200 plots were clipped. These circles were located 50 m. apart in a grid pattern covering 50 ha. in each locality under investigation. Distances were measured by pacing and grid lines were kept equidistant by using a hand compass. Twigs of all plants occuring within the 3.14m2 plots were clipped to a height of 2 m. and tallied by species. Those which could not be identified in the field were later compared with specimens at the Beal-Darlington Herbarium, Michigan State University. The number of plots needed to sample the vegetation szt2 d2 (de Vos and Mosby 1971) was found by using the formula n= where 12 13 number of samples re uired standard deviation 0 the number of twigs browsed t value at 95% confidence limit level margin of error (arithmetic mean times designated accuracy) From a pilot study, it was determined that a sample of Dad-m5 I II n u 180 plots would yield adequate results where the cover type was reasonably homogenous. Because of probable vegetative variability, 200 plots were clipped for study in each locality. For each species, the number of twigs browsed was converted to weight by using average weights per twig (Shafer 1963). Mean weights cropped by deer were determined for each plant species and area by weighing 20 unbrowsed twigs clipped at identical diameters of comparable browsed specimens. These were dried at 105’C for 2# hours in standard laboratory ovens before weighing. Though snowshoe hares (Lgpg§_§gpricg§u§) and cottontails (Sylvilaggs floridanus), occur in areas inhabited by deer, these leporids cut twigs sharply at an angle of roughly #5 degrees while deer, lacking upper incisor teeth, break the twigs more roughly. No hare or rabbit browse signs, it is believed, were misidentified as those of deer. Calculation 2; Preferred and Principal Values Cook and Stoddart (1953) considered percentage utilization as an index to preference. Petrides (1975), however, found it generally to be better to calculate preference ratings on the basis of the percentage of a plant species in the animal's diet divided by its percentage availability In in the habitat. On this basis, a preference value may be determined which centers on 1.00 as a reference point. Species with values above 1.00 are those which are preferred by the animal while those below 1.00 represent neglected or avoided forages. A ratio of 1.00 occurs for plants eaten precisely in proportion to their abundance in the field. Values according to both the Cook-Stoddart and Petrides methods were calculated in this study. Foods eaten in greatest quantities represent principal foods. These form the largest percentage of food items in the animal's diet. RaggQICondition The degree of utilization of available forage species was used as a guide to assess browsing pressure on the vegetation. As a very general rule, 50 percent of the total available annual production of a plant species can be removed without destroying its ability to regenerate (Stoddart et al. 1975). The physiological tolerance of a plant is affected by the time of forage removal, the parts removed and its association with other species present on the range (Webb 1957). Furthermore, shrubs and young trees have been found to withstand heavy utilization when cropping takes place in winter (Stoddart et a1. 1975). In the absence of specific applicable data, however, the 50 percent 15 rule was taken as a standard to judge whether or not over- browsing occured at a study site. Vegetation Clagsification The plants sampled were classified by growth as either shrubs or trees. Shrubs are woody plants which grow with a number of small stems and include such plants as sweetfern, witch-hazel and roses. Woody plants usually having only one stem or trunk are categorized as trees. Examples are pines, firs, oaks and maples. Gray's Manual of Botany (Fernald 1950) was used as a standard reference for scientific names of plants. RESULTS FggQ,Preferences White-tailed deer displayed marked differences in the winter foods utilized in various parts of their range in Michigan. Species preferred in one area often were found to be neglected in another habitat. In general, twigs of shrub species were consumed in larger quantities than were tree shoots. Shrubs were preferred over tree species on four of the five study sites (Table 1). Rose Lake Woodlots: Of the 26 woody plants growing in this area (Table 2), 21 species were neglected or avoided as forage plants. Only four species were eaten by deer to a greater extent than indicated by their abundance. In descending order of preference, they were common elderberry (Sambucus canadensis), staghorn sumac (Rhgg typhina). gray dogwood and juneberry. Black chokeberry (Eyggg melanocarpa) and white ash (Fraxinus americana), were totally avoided. In terms of bulk contribution to the deer's diet, staghorn sumac, gray dogwood and juneberry were most important. Not only were these species sought out by deer as preferred species, they also comprised 73.41 percent of the total diet and 41.65 percent of the available forage. The preference rating for common elderberry was the highest 16 1? No.0 wo.m mm.mm ww.mm em.a mm.2m memes mo.m AHWHH we.aH ea.s Hm.o mm.a mpsasm ocamso HN.H He.: mm.em oo.me nm.o Hm.ma mecca mama Nw.o so.m He.me oo.mm we.o ss.ma mosaam mcammam mm.o mm.s mm.ma mw.mH No.0 mm.m memes ween mo.H ms.ma we.sm AH.om mn.e mm.mn eschew copamsom Hm.o ua.m oe.H Hm.m 00.0 em.w memes macaw mo.H ea.me om.mm me.mm as.me oo.ao mpsanm seaoo me.o mm.s Hm.ma so.mm Ne.H mo.mH mecca messed: mN.H 0H.Nm m . m mm.mm d:.m ma.mn wnoanm oxmg omom mMprma wav .6: “.mxv .m: Paps: woa< cosmnmmmam um>oemm scam 2H maomafim>< vasomaoo oaomafim>¢ £93090 mmmmammMHMm up: we; c m mam>< .mmma amps“: .hpwamooa Some CH mmHQEMm com :0 woman mommmao ommaow as some ooHHManpwsz mgr an :mvmm was oHpmawm>m QOHPMmem> Mo mommvcooaom .H canoe 18 00.0 30.50 00.000 00.000 00.0 00.00 00000 00.0 00.0 00.0 30.0 00.0 00.0 500.0 000000000 00000000 00.0 00.0 00.0 50.0 00.0 00.0 030.0 0000000000s 0:000 0.0 w3. 0 03.0 00.0 30.0 00. 0 000.0 .000 20000000> 0.03.0 00.0 0.0 00.0 00. 0 000.0 000000000000 00000 00.0 0M. 0 00.0 5.0 00.0 00.0 003.0 0000000 000000 00.0 30 .3 00.0 00.0 00.0 00.3 000.0 000000020 00200 00.0 00. 3 00.0 00.0 00.0 00.0 003.0 00000000000 s000000> 00.0 30. 0 00.0 00.0 00.0 55.0 050.0 000000 00000 00.0 00. 0 00.0 00.0 00.0 00. 0 050.0 0000000000» 000000000 00.0 00.0 03.0 00.0 30.0 00. 0 000.0 0000o0=s000 0000000 00.0 00.0 00.0 00.0 00.0 00.0 000.0 0:00:00> 0500000 50.0 03.0 05.0 00.0 50.0 00. 0 500.0 .000 0000 03.0 0.5 05.0 35.0 50.0 00. 0 000.0 .000 000000000 00.0 0.5 00.0 0N.0 00.0 05.0 000.0 00000000000000 0:00 N3.0 30.5 03.0 0 .0 30.0 00.0 000.0 0000:0000> 00000000: 3.0 00.0 03.0 00.0 30.0 53.0 000.0 0000001000000 000000 05.0 00.00 00.0 50.5 00.0 0 .0 000.0 £30900 000< 05.0 00.00 05.0 00.0 50.0 0 .0 000.0 0900 0500030 05.0 05.00 0.0 00.3 00.0 05.0 000.0 sssosm 000000 05.0 05.00 0.0 00.0 00.0 00.0 000.0 .000 00000000 00.0 00.00 00.0 00.0 00.0 00.0 000.0 0000000008 0000000 00.0 00.00 05.0 05.0 50.0 00.0 000.0 000008500 000000000 00.0 00.00 00.00 00.50 00.0 05.0 000.0 .000 000002000e< 55.0 50.00 00.00 00.00 00.0 00.5 000.0 00080000 000000 00.0 00.50 00.00 00.00 00.0 00.0 005.0 020000» 0000 00.3 00.05 00.0 50.0 00.0 00.0 003.0 0000000000 00000000 «\n 0\0 000 000000 0000 .0: 0.000 .0: 0.000 00:00> 00>0Emm 0000 :0 0000000>< 00500000 0090000>< 0039 000 0000000 000 A00 000 000 0000000 0020000000 00000000000 0000003 000 00000>< .0500 000003 .00000002 .000500 0000000 .0000 000000 0000 0000 00 0000 000000109003 0:0 00 00000000000 0000 .0 00909 19 of all and was nearly twice as high as its nearest competitor. Yet, because of its scarcity, this food made up only 1.12 percent of the animal's diet. Deer concentrations in the Rose Lake area during winter are high. Five hundred animals are estimated to use the area then (Belyea, pers. comm. 1979). In comparison to the lowland Corey Swamp, however, the upland forage was not utilized heavily. Only 17.5h percent (Table 2) of the available browse was consumed by deer there, while a total consumption of 42.80 percent occurred in the Corey Swamp (Table 3). These data tend to confirm that deer are animals of shrublands (Figure 7) and early successional woodland stages, rather than of mature forests (Figure 6; see also Severinghaus and Cheatum 1969). On the uplands. 70 percent of browse utilization was found to occur in woodlots near corn fields. Corn was cultivated hy DNR personnelin provide supplemental food for deer during winter. It was heavily used so long as the supply lasted (Belyea, pers. comm. 1979). Deer also made use of available crops in private fields surrounding the station. Crop damage, though not alarming, was reported by farmers to occur in the area. The dependence of deer on the crop during the coldest part of winter was an unmeasured factor which certainly affected utilization of browse by deer in the area. 20 00.0 00.00 00.000 00.000 00.00 00.000 00000 00.0 00.0 00.0 00.0 00.0 00.0 000.0 000000 00000 00.0 00.0 00.0 00.0 00.0 00.0 000.0 00000 000000 00.0 00. 00.0 00.0 00.0 00.0 000.0 000000000 00000 00.0 00. 00.0 00.0 00.0 00.0 000.0 00000000000 00000 00.0 00.0 00.0 00.0 00.0 00.0 000.0 00000000000 00000000 00.0 00.00 00.0 00.0 00.0 00.0 000.0 0000000 0000 00.0 00.00 00.0 00.0 00.0 00.0 000.0 .000 00000000 00.0 00.00 00.0 00.00 00.0 00.00 000.0 .000 0000000 00.0 00.00 0.0 00.0 00.0 00.0 000.0 .000 000000000 00.0 00.00 0.0 00.0 00.0 00.0 000.0 .000 0000 00.0 00.00 00.0 00.0 00.0 00.0 000.0 0000000 00000000 00.0 00.00 00.0 00.0 00.0 00.0 000.0 000000 0000 00.0 00.00 00.0 00.0 00.0 00.0 000.0 .000 00000 00.0 0N.00 00.0 00.0 00.0 00.0 000.0 000000 000000 00.0 0 .00 00.0 00.0 00.0 00.0 000.0 000000 00000 00.0 00.00 00.0 00.0 00.0 00.0 000.0 00000000 00000000 00.0 00.00 00.00 00.00 0m.0 00.00 000.0 00000000 000000.. mm.o No.00 mm.0 nn.0 m .o mm.0 onn.o .000 N000m 00.0 00.00 00.0 00.0 00.0 00.0 00 .0 0000000000 00000000 0.0 00.00 00.00 00.00 0.00 00.00 00 .0 000000 000000.. m.0 mm.mm 00.0: mm.om o.m0 m0.00 000.0 00000000000 mzchoo- «\0 0\0 000 00500> 00>050m 0m0000 Amxv .00 A.wxv .00 0.0wv 0000 00 000000000 00000000 000000000 0000 000 000 000 000 000 wwww0000000 0000000 mwd000m 0000000000 .0000 00000; .00m00002 .z0qsoo 0000000 .00803m 000oov 00000300 0000 0000 .0000 000000I00003 000 00 000:0000000 0000 .m 0000a 22 Rose Lake Lowlands: Twenty-one species were recorded in the Corey Swamp lowlands on the Station. There. red-osier dogwood. silky dogwood and common elderberry were the preferred winter deer forages (Table 3). Gray dogwood. though contributing 17.38 percent of the total diet. was a slightly- neglected food. Red-osier, silky and gray dogwoods comprised 68.42 percent of the available forage there and 8h.50 percent of the bulk contribution to the deer's diet. Spirea (Spiraea spp.), which ranked fourth in the percentage of available forage, constituting 10.9h percent of the browse, was not eaten to the degree warranted by its abundance. Pignut hickory (gagya glabra) was entirely avoided on this site. Of all the study areas, Corey Swamp was the most heavily eaten. Though supporting dense and abundant forage (Figure 3), a removal of #2.80 percent of the available browse occurred there. It was evident that the number of deer using the area was high during winter. This heavy cover was used to provide both maximum protection from cold winds and adequate food as found by Ozoga and Verme (1968). Houghton Lake: Of the 2a forage species tallied in this. mid-state area, exactly half were preferred as foods by deer (Table 4). In descending order of preference, the favored group included nannyberry (Viburnum lentago), 23 00.H Hn.HH 00.00H 00.00H no.3 nm.mo Haven 00.0 00.0 00.0 no.m 00.0 no.H 0ma.0 mosomHon monp< 00.0 00.0 00.0 no.0 00.0 no.0 0:n.0 sssmonnosm sonnxosvnmx 00.0 00.0 00.0 no.0 00.0 no.0 onn.o ounmflm «ammo 30.0 nn.0 0:.0 an.m No.0 mw.m mmN.0 opmasonamo wcsmmoodsmso no.0 nn.0 0:.0 n.n «0.0 on.m Hom.0 onmwmxcop woman nH.0 mm.H mw.m 0.0H mH.0 0m.w mmH.0 .mnm Bananoom> oo.0 nm.n 0m.0 no.0 no.0 oH.0 onH.0 moonomfin mopzm on.0 oo.n 0:.0 on.0 No.0 on.0 00N.0 .oom momoopmoo nn.0 nm.n n0.~ 0m.n on.0 on.H nHN.0 unmaonconmoaao mopom on.0 n .n n0.n 0n.s nn.0 mo.H onN.o moonoaosoop monsoon nn.0 nn.o nm.n no.o nn.0 0m.: mnn.o .oom ammonom no.0 HH.HH 0m.0 Hm.o no.0 o0.0 0HH.0 msooow mason n0.H 00.NH NN.H 0N.H no.0 on.0 an.o .oom «mom 00.H ow.mH mm.n mo.m nn.0 mN.H nwm.0 mcwonumem mscnxmhm :N.H 0:.sa m0.m mw.H on.0 on.0 mmm.0 mmnwoonome m50pmzo Ho.a o:.nH nm.n om.m nn.0 no.0 noH.0 mongoosonos manna Nw.H 30.0H N@.H 00.H m0.0 N:.0 0mm.0 maQSh msommsa nn.H on.0m mm.mm an.mH 0H.H om.n nnm.0 .oom noncoconos< on.H no.0m :n.nH nn.n nn.0 0N.n oom.0 monsooomm oncovmsoo oo.H mn.mm H0.H mn.0 no.0 N~.0 0nm.o «mosoomn mzcuoo oH.N Nn.nm no.nm Ho.mH on.H nm.n onn.0 .oom unflwm nn.~ no.nm No.H on.0 o0.0 nn.0 00n.0 ssopoo noo< mm.m 00.03 03.0 NH.0 No.0 no.0 00m.0 sssosm machoo oo.o nn.mn no.n nn.H on.0 nn.0 nmm.0 ommpcoa sscusnn> ¢\Q M\o 00H owwpom wav .m: A.wxv .m: .pm 0m>osom gown CH mannanm>< uoEfimcoo mewHHm>< maze pom A00 A nn.0 00.n no.~ nm.0n no.0 00.n onm.0 mopoopm manna 03.0 o3.H 0o.H N .3 No.0 nn.H 0nn.0 mannewwnn> mnamsmsmm nn.0 30.N no.m ma.n no.0 n3.H 00m.0 monsoonamo mongoooososo H0.0 mm.n Hw.m ma.3 0.0 0N.H 0mm.0 mnHm machosa nH.H nm.3 mn.NH 00.0H H.0 30.m 0mm.0 ammonnmsm mSEHD HN.H 33. Nn.n om.n o0.0 0o.a 0nn.0 annoy msooozo on.H mo. o3.0n oH.oH Nn.0 0n.n nnm.o .oom nonnonoaos< oH.n an.HH nn.3~ 3n.n nm.0 mm.m 00n.0 season omo< nn.n nn.nH 0o.H mn.o No.0 nH.0 onm.o moofioflosooo monsoon 0o.H 33.33 Hm.n Nn.0 30.0 o0.0 nmm.o ommpcoa ssouspn> ¢\Q M\o 00H mmmnom wav .m: A.wxv .mn .pm mosam> 0m>osom pong SH mammawm>¢ omszmcoo manmanm>< maze pom mmcwpmm mocmhmmopm n00 n< QoEEoomom .mvnm onwam: mxmg mcnwwnm .pmmo 0mandpumpn£3 one no mmocmpmmmnm 000m .onoH “open; .cmmnnons .necsoo .n mason 26 percent of the available forage and comprised 67.62 percent of the diet. Though two species of conifers, white pine and balsam fir, made up 15.51 percent of the total available forage they constituted only 3.81 percent of the browse consumed. Cusino: Only 13 species of woody plants were encountered on the sample plots. The low diversity of vegetation may be related, however, to the elimination.of some species at browsing level. These formerly may have occurred in the fenced area but extirpated or drastically reduced by overbrowsing deer. Arnold and Verme (1963) in a ten-year study of the area reported that deer markedly-overbrowsed some of the preferred species. American yew (Taxug canadensis), they said, was eliminated. Similarly, white cedar (Thuja.occidentalis) was reported by them to be reduced to 80 percent of its original availability. During the present study, neither Taxg§_nor Thgjg_was encountered on the clip plots. In order of species preference, juneberry, American elm. honeysuckle (Lonicera spp.), red raspberry and red maple were the most preferred food plants. No browsing was observed on jack pine, red pine, bristly blackcurrant (fiibgg lggggigg) or blackberry. In terms of bulk contribution to the diet, red maple, balsam fir, American.eln|and juneberry were taken in large 2? 00.H mn.n 00.00H 00.00H n3.H nm.nm Hopoo 00.0 00.0 00.0 no.0 00.0 No.0 nHN.0 mfimcowconmoanm monom 00.0 00.0 00.0 00.na 00.0 nn.3 003.0 «mosfimoo mscnm 00.0 00.0 00.0 3n.0 00.0 3H.0 nHH.0 mcmfimxnmp woman 00.0 00.0 00.0 N3.0 00.0 HH.0 m3H.0 manSOMH manna mm.0 om.H 0w.0 33.N no.0 30.0 nNH.0 mozmam moonm nn.0 3m.H mm.m mm.ma w0.0 nn.3 0mm.0 maneuvm macam nn.0 3o.m on.H on.m No.0 on.0 noH.0 .oom sonsfiooo> nn.0 on.n 0H.nH mm.0m on.0 an.n 0nn.0 mosmmnmn monp< mm.H N0.0H 0 .3m 00.0m on.0 00.n 00m.0 esnpsn hoo¢ m0.m HH.HH m .H mm.0 No.0 mn.0 mHH.0 mammon mansm 0n.m on.NH on.0 on.0 no.0 no.0 n0H.0 .oom «noonnoq 0n.m ww.ma mn.HH 0H.m nn.0 3m.H 0mm.0 manonnmem moan: wn.n nn.oH n0.HH 00.n nH.0 no.0 nnm.0 .oom nongosmaoso‘ <\Q M\o 00H mmmuom wav .m: A.wxv .m: .nm mosam> um>oEmm Penn CH mapmawm>< owszmzoo mammanm>¢ wage Mom nov A