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White-tailed jackrabbits (Lepus townsendii) were once abundant in North America and provided a number of ecosystem services such as seed dispersal, nutrient cycling, facilitating the persistence of other species, and serving as a prey species for predators, including golden eagles (Aquila chrysaetos), bobcats (Lynx rufus), and numerous others. Reports describe declines and extirpations across much of their range, but given the extremely limited research available, it is difficult to determine what factors have led to reductions of white-tailed jackrabbits. Researchers have investigated few areas of white-tailed jackrabbit ecology, including the possible effects of climate change, habitat degradation and loss, competition with black-tailed jackrabbits (Lepus californicus), and changes in predator composition. We review the life history and research available on white-tailed jackrabbits, discuss possible causes of their decline, suggest areas that require additional research, and make recommendations regarding their management.

The distribution and abundance of the white-tailed jackrabbit Lepus townsendii have declined significantly since 1950, continuing a trend that began in some regions of its range in the late 1800s. We reviewed museum records and the literature to evaluate the status of the white-tailed jackrabbit in each state and province in its historical range and evaluated possible reasons for its decline. Our evaluation revealed its extirpation or decline throughout much of its range, but its legal or conservation status does generally not reflect this precarious status. We note its extirpation in Missouri, Kansas and Oklahoma, and potential extirpation in British Columbia, Oregon, Illinois, and Wisconsin. We classified the white-tailed jackrabbit to be broadly extirpated in Iowa, Minnesota, Washington, Nebraska and California, and declining with local extirpations in Wyoming, Nevada, Utah, Colorado, New Mexico, and South Dakota. We consider it to be a relict in Ontario, and possibly declining in Alberta, Saskatchewan, North Dakota, Idaho, and Montana. We consider only Manitoba to have a possibly stable population. Determining the reasons for the species' reduced distribution is difficult, as the decline appears to be due to multiple factors, none of which provide a universal explanation. We dismissed road kills, recreational hunting, disease and parasites, and competition with black-tailed jackrabbits Lepus californicus as causes of the widespread population declines and extirpations. We concluded that habitat alterations and climate change are overriding factors, and that past depredation measures and increased predator populations have likely contributed to the decline. These hypotheses require further testing. We recommend more research on the distribution, abundance, ecology, and population dynamics of white-tailed jackrabbits, and management that includes a frank appraisal of the species' status, the potential for grassland restoration, and programs to reintroduce populations into prairie preserves and restored grasslands.

The loss and fragmentation of Iowa’s native prairies has had varied effects on different species as some move more easily through unsuitable habitat than others. Small mammals may be highly affected by isolation as they may not move easily among habitat patches. I studied white-tailed jackrabbits (Lepus townsendii) as a representative of Iowa’s grassland-adapted species to determine effects of habitat fragmentation on movement patterns, space use, and genetic diversity. I tracked radio-collared jackrabbits from September 2008-September 2009 to determine habitat use in an intensively agricultural landscape. I collected tissue from live-captured animals and road-killed samples across Iowa and South Dakota. Home ranges expanded and shifted following corn harvest (October 2008) and prior to the breeding season (February-May 2009). Home ranges contracted from the end of the breeding season until right before harvest (September 2009) as crop height increased. The population genetic structure analyses suggested there were two populations in Iowa, a central and northwestern population. The northwest Iowa population is not distinct from South Dakota individuals and is moderately differentiated from the less genetically diverse central Iowa population. White-tailed jackrabbit movement patterns are affected by agricultural practices and agricultural fields are a potential barrier to gene flow. These anthropogenic alterations of the landscape in Iowa may also alter other aspects of jackrabbit ecology and other grassland-adapted species.

Across the western United States, Leporidae are the most important prey item in the diet of Golden Eagles (Aquila chrysaetos). Leporids inhabiting the western United States include black-tailed (Lepus californicus) and white-tailed jackrabbits (Lepus townsendii) and various species of cottontail rabbit (Sylvilagus spp.). Jackrabbits (Lepus spp.) are particularly important components of the ecological and economic landscape of western North America because their abundance influences the reproductive success and population trends of predators such as coyotes (Canis latrans), bobcats (Lynx rufus), and a number of raptor species. Here, we review literature pertaining to black-tailed and white-tailed jackrabbits comprising over 170 published journal articles, notes, technical reports, conference proceedings, academic theses and dissertations, and other sources dating from the late 19th century to the present. Our goal is to present information to assist those in research and management, particularly ...

Distribution of white-tailed jackrabbit ( Lepus townsendii ) and black-tailed jackrabbit ( L. californicus ) populations have been thought to be shifting throughout the Northern Great Plains. Anecdotal reports of population declines of white-tailed jackrabbits in recent years have created concern for wildlife managers. We established 21 spotlight line transects (64.4 km) across South Dakota to evaluate jackrabbit distribution as well as to facilitate future survey efforts. We conducted surveys during 2004 and 2005 to obtain baseline information about jackrabbit distribution and population density throughout the state. We observed white-tailed jackrabbits throughout the state, and estimated the highest population density in the northwestern part of the state and lowest in east-central South Dakota. We only observed black-tailed jackrabbits at very low densities in south-central South Dakota in Tripp and Gregory Counties.

During 1994–2008, 58 adult and 195 juvenile eastern cottontail rabbits (Sylvilagus floridanus (Allen)), one adult and 23 juvenile snowshoe hares (Lepus americanus Erxleben), and eight adult white-tailed jackrabbits (Lepus townsendii Bachman) (Mammalia: Leporidae) were examined for ectoparasites. The most abundant ectoparasite on cottontails was the sucking louse, Haemodipsus setoni Ewing (Phthiraptera; Polyplacidae), recorded from this host for the first time. Infestations in adult and juvenile cottontails were highly aggregated, k = 0.136 and 0.153, respectively. Prevalence of infestation in adult cottontails was 70.6%, with a mean intensity of 5614.1 (range: 1–166 249); 10 adults had more than 1000 lice. In juvenile cottontails, prevalence was 34.8% and mean intensity was 6.2 (range: 1–87). On adult cottontails, 73.4% of the total lice were nymphs, while on juvenile cottontails only 11.6% were nymphs. It appears that dispersal from parents to offspring is overwhelmingly achieved by adult lice. Seventeen adult cottontails were infested with the tick, Haemaphysalis leporispalustris (Packard) (Acari: Ixodidae). No fleas specific to rabbits were collected but small numbers of the rodent fleas Monopsyllus vison (Baker), Orchopeas caedens (Jordan), and Aetheca wagneri (Baker) (Siphonaptera: Ceratophyllidae) were recorded. Only one snowshoe hare was infested with H. setoni and three were infested with H. leporispalustris; no fleas were found on snowshoe hares. Two white-tailed jackrabbits were infested with H. leporispalustris; one carried Pulex irritans Linnaeus (Siphonaptera: Pulicidae), and none carried lice.

Food habits of cougars (Puma concolor) in North America have been documented for western populations in the United States, Canada and Mexico. Most studies assessed diets of cougars occupying typical habitats, and within established populations. We evaluated food habits of cougars in prairie and agricultural landscapes in the Dakotas (regions that had been devoid of the species for roughly a century) located well outside of known resident populations. We obtained stomach and gastrointestinal (GI) tracts from 14 cougars (10 male; 4 female) from 2003–2007, and evaluated contents via frequency of occurrence (%) of various prey items. Deer (Odocoileus spp.) had the highest frequency of occurrence (50.0%). Other native mammalian prey included jackrabbit (Lepus townsendii, L. californicus), porcupine (Erethizon dorsatum), beaver (Castor canadensis), badger (Taxidea taxus), mink (Mustela vison) and rodent species (e.g., vole). No domestic livestock species were documented as part of the cougar diet in th...

Phylogeographical investigations of arctic organisms provide spatial and temporal frameworks for interpreting the role of climate change on biotic diversity in high-latitude ecosystems. Phylogenetic analyses were conducted on 473 base pairs of the mitochondrial control region in 192 arctic hares (Lepus arcticus, Lepus othus, Lepus timidus) and two individual Lepus townsendii. The three arctic hare species are closely related. All L. othus individuals form one well-supported clade, L. arcticus individuals form two well-supported clades, and L. timidus individuals are scattered throughout the phylogeny. Arctic hare distribution was altered dramatically following post-Pleistocene recession of continental ice sheets. We tested for genetic signatures of population expansion for hare populations now found in deglaciated areas. Historical demographic estimates for 12 arctic hare populations from throughout their range indicate that L. arcticus and L. othus persisted in two separate North American arctic refugia (Beringia and High Canadian Arctic) during glacial advances of the Pleistocene, while the high genetic diversity in L. timidus likely reflects multiple Eurasian refugia.

Two white-tailed jack rabbits (Lepus townsendii) with proliferative lesions in their internal organs were submitted to the Canadian Cooperative Wildlife Health Centre (Saskatoon, Saskatchewan, Canada) for necropsy because of concern that dogs that had contact with the hares might have been exposed to an infectious disease. In both hares, the primary diagnosis was neoplasia. One hare had metastatic leiomyosarcoma and uterine fibroma, the other had metastatic mesenchymal tumors involving the liver and mesentery. These cases represent the only reports of malignant mesenchymal tumors in white-tailed jack rabbits that we have found in the literature.

The bacterium Listeria monocytogenes causes disease in a wide variety of mammals including rabbits and hares. We describe naturally acquired metritis and septicemic listeriosis in wild female hares from Saskatchewan, Canada. Between April 2012 and July 2013, two white-tailed jackrabbits (Lepus townsendii) and a snowshoe hare (Lepus americanus) were presented to the Veterinary Medical Centre at the Western College of Veterinary Medicine, Saskatoon, Saskatchewan, Canada with nonspecific neurologic signs. The hares were euthanized and autopsied. Necrotizing fibrinosuppurative metritis was present in all. Additional findings in individual hares included fetal maceration, multifocal necrotizing myocarditis, multifocal hepatic necrosis, and nonsuppurative encephalitis. Listeria monocytogenes was cultured from multiple tissues in each hare. Although listeriosis in pregnant domestic rabbits has been studied, this is the first detailed description in wild North American hares. The epidemiology of listeriosis, including prevalence and the role of environmental sources and coprophagy in transmission among hares, requires further investigation.

Archaeological investigations in Camels Back Cave, western Utah, recovered a series of small-mammal bone assemblages from stratified deposits dating between ca. 12,000 and 500 14C yr B.P. The cave's early Holocene fauna includes a number of species adapted to montane or mesic habitats containing grasses and/or sagebrush (e.g., Lepus townsendii, Marmota flaviventris, Reithrodontomys megalotis, and Brachylagus idahoensis) which suggest that the region was relatively cool and moist until after 8800 14C yr B.P. Between ca. 8600 and 8100 14C yr B.P. these mammals became locally extinct, taxonomic diversity declined, and there was an increase in species well-adapted to xeric, low-elevation habitats, including ground squirrels, Lepus californicus and Neotoma lepida. The early small-mammal record from Camels Back Cave is similar to the 11,300–6000 14C yr B.P. mammalian sequence from Homestead Cave, northwestern Utah, and provides corroborative data on Bonneville Basin paleoenvironments and mammalian responses to middle Holocene desertification.

White-tailed jackrabbits ( Lepus townsendii ) were observed using radiotelemetry and focal observations to evaluate factors affecting locomotor activity and foraging effort. Individuals were highly synchronous in onset and cessation of locomotor activity. Locomotion began ca. 1 h after sunset and ceased before sunrise throughout the year. Hence, the nightly activity period varied inversely with photoperiod. Distance, duration, and frequency of locomotion increased during the early breeding season, March and April, and declined during warm months of the study, May and June. Low ambient temperature, cloud cover, and precipitation had no significant effect on locomotor or foraging activity of this well-insulated leporid ( P > 0.05). However, a decline in locomotor activity and an increase in foraging effort occurred when snow cover was present. Trends associated with predation included reduced locomotor activity during periods of greater lunar illumination and an increase in speed of movement when predators (coyotes, Canis latrans ) vocalized.

The population structure and pattern of individual growth of white-tailed jack-rabbits ( Lepus townsendii ) was studied in Wyoming and compared with results for more easterly populations in North America. The density of white-tailed jackrabbits in Wyoming was ca. 7/km2 and relatively constant during 1985–1987. Sex ratios of adults and young of the year were near 1:1. Age distributions of each sex were similar, with younger animals predominant. Typical lifespans of wild white-tailed jackrabbits were estimated to be 90% of the variance in age-specific body masses was explained by fitting von Bertalanffy, Gompertz, logistic, or Richards sigmoid equations to data. Postnatal growth rates of white-tailed jackrabbits were 18–30 g/day during the linear phase of growth (20–80 days). A comparison of these results with those for other regions indicated little geographic variation occurs among populations of L. townsendii .

Large protected areas are often considered natural yet outside pressures may compromise ecolog- ical integrity. This paper points to a problem in assessing ecological baselines: what if species' extirpations go undetected? I present a data set spanning 130 years that demonstrates the loss of white-tailed jack rabbits Lepus townsendii from two National Parks in the well studied 60,000 km 2 Greater Yellowstone Ecosystem, USA. While these extirpations have been unnoticed until now, an ecological consequence may be elevated predation on juvenile ungulates. A critical challenge we face is how to apply better the concept of shifting baselines to the restoration of functional relationships when species' losses are undetected.

Standard metabolic rate was higher ( P < 0.001) in winter- than in summer-acclimatized white-tailed jackrabbits ( Lepus townsendii ). Standard metabolic rate in summer did not differ significantly from the expected basal rate for eutherian mammals, but standard metabolic rate in winter was higher ( P < 0.001) than expected. Jackrabbits had thicker pelage ( P < 0.001) and lower overall thermal conductance ( P < 0.001) during winter. Body temperatures were higher ( P < 0.001) in winter- than in summer-acclimatized jackrabbits, and the ratio of standard metabolic rate to overall thermal conductance also was highest in winter. Variation in standard metabolic rate and thermal conductance contributed to a reduction in the lower critical temperature by 17°C from summer to winter. Decline in lower critical temperature and in thermal conductance lowered energy expenditure in winter; decline in standard metabolism lowered energy expenditure in summer. Jackrabbits expend minimal energy for thermoregulation at ambient temperatures usually occurring in their natural habitat. At air temperatures 15°C below lower critical temperatures, energy metabolism increased only to 1.50 and 1.35 times the standard metabolic rate in summer and winter, respectively.

1. 1.High wind speed and low air temperature interact and increase the metabolic rate of white-tailed jackrabbits ( Lepus townsendii ); this effect is greater in summer than in winter. 2. 2.Most variance in metabolism is explained (approx. 90%) when a term for the temperature—wind interaction is included in regresson models. Metabolism is best described with linear terms for wind in summer, and non-linear terms for wind in winter regression equations. 3. 3.Core temperature increases with wind; heat production apparently overcompensates for convective heat loss. 4. 4.Metabolic rate was reduced with 540 and 1080 W/m 2 irradiance (0.3–2.8 μ) at air temperatures below the lower critical temperature in winter. There was no reduction in summer with 400 W/m 2 , perhaps due to decreased penetrance of radiation into brown pelage. 5. 5.Mean ground-level wind speeds in sagebrush habitat are low throughout the year and should usually have minimal influence on metabolic rate. High winds and low air temperatures during severe winter storms may radically elevate metabolic heat produced for thermoregulation.

We observed White-tailed Jackrabbits (Lepus townsendii) eating spike plants (Cordyline australis), a non-native ornamental garden plant, in our front yard within the city of Edmonton, Alberta. We have noted this persistent behaviour every winter between 2006-2007 and 2011-2012. By late January, the plants were usually eaten right down to the stem base. We suggest that the White-tailed Jackrabbits turn to this food source in winter when more preferred foods are lacking, are in short supply, or are not as readily accessible. Our observations add another plant species to the list of non-native plants consumed by White-tailed Jackrabbits.

Lepus townsendii Bachman, 1839. J. Acad. Nat. Sci. Philadelphia, 8(1):90. TYPE LOCALITY: "...on the Walla-walla...river"; restricted by Nelson (1909:78) to Fort Walla Walla, [near present town of Wallula, Walla Walla Co., Washington]. DISTRIBUTION: C Alberta and Saskatchewan east to extreme SW Ontario (Canada), south to SW Wisconsin, Iowa, NW Missouri, west through C Kansas to NC New Mexico, west to C Nevada, EC California (USA) and north to SC British Columbia (Canada). STATUS: Has withdrawn from parts of its southeastern (Wisconsin, Iowa, Missouri, Kansas, S Nebraska) distribution, perhaps because of habitat alteration. Stable in remainder of range (Flux and Angermann, 1990). SYNONYMS: campanius Hollister, 1915; campestris Bachman, 1837; sierrae Merriam, 1904. COMMENTS: Placed (as campestris) in subgenus Proeulagus by Gureev (1964:190). Reviewed by Lim (1987, Mammalian Species, 288)., Published as part of Robert S. Hoffmann, 1993, Order Lagomorpha, pp. 807-827 in Mammal Species of the World (2 nd Edition), Washington and London :Smithsonian Institution Press on pages 821-822, DOI: 10.5281/zenodo.7353088, {"references":["Nelson, E. W. 1909. The rabbits of North America. North American Fauna, 29: 1 - 314.","Flux, J. E. C., and R. Angermann. 1990. The hares and jackrabbits. Pp. 61 - 94, in Rabbits, hares and pikas (J. A. Chapman and J. E. C. Flux, eds.). I. U. C. N., Gland, Switzerland, 168 pp.","Gureev, A. A. 1964. Fauna SSSR, Mlekopitayushchie, tom. 3, vyp. 10, Zaitseobraznye (Lagomorpha) [Fauna of the USSR, mammals, vol. 3, pt. 10, Lagomorpha]. Nauka, Moscow-Leningrad, 276 pp. (in Russian).","Lim, B. K. 1987. Lepus townsendii. Mammalian Species, 288: 1 - 6."]}

We collected and analyzed pellets from known roosts of great horned owls (Bubo virginianus) on shortgrass prairie in N-central Colorado between 1992 and 1994 to examine seasonal trends in owl diets. We also compared the species composition of small rodents in owl diets to the relative abundances of rodents on the study area. In all seasons, lagomorphs (desert cottontails Sylvilagus audubonii, black-tailed jackrabbits Lepus californicus, white-tailed jackrabbits Lepus townsendii) comprised most of the diet biomass. Northern pocket gophers (Thomomys talpoides) were also preyed upon in all seasons, with the highest percentage consumed in spring. Most of the individual prey items taken were rodents, primarily deer mice (Peromyscus maniculatus). Comparisons of diet composition with measures of rodent abundance suggested that owls foraged over a relatively restricted part of our study area, especially in winter. Most prey apparently were taken from roadsides, buildings and an adjacent four-wing saltbush (Atriplex canescens) floodplain, where rodent densities remained relatively higher in all seasons than in the surrounding vegetation. We speculate that the preferential use of these foraging habitats may reflect the availability of suitable hunting perches on the site.

Reproduction in lagomorphs may be sensitive to adverse winter conditions or summer drought. Consequently, I studied white-tailed jackrabbits (Lepus townsendii) in Wyoming, from 1985 to 1987, to evaluate their reproductive pattern and fertility on semi-arid range. The breeding season of white-tailed jackrabbits began between late February and mid-March and ended in july. Breeding began later in 1986 and 1987 (2 yr with sparse snow cover) than in 1985 (when greater late-winter snow accumulation occurred). I detected no effect of ambient temperature on the onset of breeding. Reproductively active females conceived in approximate synchrony, and litters were produced during 3 distinct periods each year

1. This paper explores the relationship between energy expenditure, body size and the capacity for homeothermy in young of a precocial mammal. 2. Metabolism and rectal temperature (T b ) were measured during postnatal development in 4-81-day-old white-tailed jackrabbits (Lepus townsendii). 3. Whole-animal metabolism increased with age, mass-specific metabolism decreased with age, and mass-independent metabolism showed no age-related change. 4. Jackrabbits 4-5 days old responded to low ambient temperature (T a ) by increasing metabolism, but nonetheless, their T bS declined at low T a

Aspergillus leporis NRRL 3216 (A. jlavus group), first isolated from white-tailed jaclcrabbit dung, survived passage through the digestive system ofa caged laboratory rabbit and produced both conidial apparati and sclerotia on dung surfaces during subsequent moist chamber incubation. Sclerotium-producing strains of Aspergillusjlavus NRRL 3357 and Aspergillus parasiticus NRRL 13,005 produced conidial apparati on dung but not sclerotia. Aspergillus leporis States & Christensen NRRL 3216 was isolated initially from white-tailed jackrabbit (Lepus townsendii Bachman) dung collected in Wy­ oming (States and Christensen, 1966). Christensen (1981) proposed that A. leporis is a segregate from the Aspergillus jlavus group adapted to sagebrush-grass1and communities of North America where it has also been isolated from soil samples. Professor J. S. States (pers. comm.) observed that the jackrabbit dung was collected from the rectum ofa freshly-killed animal and never contacted the soil. According to States the fungus was isolated by transfer of conidia from columnar conidial heads that were produced when the dung collection was incubated in a laboratory moist chamber. No sclerotia were observed until the organism was cultured on Czapek's agar. Is the life cycle of A. leporis in some way linked to a coprophilous habit? Can A. leporis survive gut passage through a rabbit? Do sclerotia of A. leporis form on rabbit dung? This research was organized to address such questions about A. leporis as contrasted with two other sclerotium-producing members of the A. jlavus group (i.e., Aspergillusjlavus Link ex Fr. and Aspergillus parasiticus Speare).

Analysis of vertebrate faunas from archaeological sites in south-central Oregon's Fort Rock Basin supports the hypothesis that the common early Holocene jackrabbit in the northern Great Basin was Lepus townsendii , and that L. californicus did not become abundant in this area until middle Holocene times. The current range expansion of L. californicus at the expense of L. townsendii in the northern Great Basin and adjacent Plateau may, in part, represent the continuation of a process that began several thousand years ago. These faunas also document the presence of pikas ( Ochotona princeps ) in the Fort Rock Basin prior to, but not after, 7,000 years B.P. Pikas are absent from the area today; their disappearance here may have been due to the eruption of Mt. Mazama at, or just before, an episode of climatic change. These data support the argument that the distribution of boreal mammals on mountainous islands within the Great Basin can be accounted for by initial colonization followed by extinctions of geographically intermediate populations.

Field and laboratory studies were conducted to develop a model of energy expenditure in a population of white-tailed jackrabbits (Lepus townsendii). Field work in southwestern Wyoming during 1985-87 showed that the breeding season commenced at snowmelt and ceased during late- July drought. Adult females reproduced relatively synchronously and produced a mean of three litters annually. Greatest fetal production occurred in the second litter period. Collections indicated a 1:1 sex ratio, few jackrabbits >2 years-old, and a density of 7 animals / km2 in the population. Postnatal growth was sigmoidal, culminating in heavier adult females than males. Using radio -telemetry, a circadian rhythm was detected in jackrabbit activity, with movement beginning after sunset and ending by sunrise. Observations showed that season, snow cover, weather, lunar phase, and predators influenced activity. Energetics studies established the pattern of seasonal acclimatization in the jackrabbit. Basal metabolic rate (BMR), pelage thickness, and body temperature increased but overall thermal conductance (C) and the lower critical temperature (LCT) declined from summer to winter. High winds and low air temperatures elevated metabolism interactively and their effects were most pronounced during summer. Metabolic rate dee lined with incident radiation at Ta< LCT during winter but not during summer. In newborn jackrabbits, body temperature dropped despite increased metabolism at Ta< 25��C. Cold tolerance and homeothermy developed with age. Based on these and published data, a FORTRAN model was written that simulated the energy expenditure of a population of jackrabbits. Metabolizable energy requirements for maintenance , thermoregulation, reproduction, growth, and activity were estimated. The model indicated that most energy (kJ��kg - l.day- 1) was required by adult females during lactation, adult males at the onset of breeding, and newborn juveniles. Energy expenditures for adult females, adult males, and juveniles were 191, 130, and 224 MJ��individual-1��km-2��yr-1, respectively. Total energy expenditure increased with wind and lower air temperature and decreased if juvenile huddling was simulated. The model indicated that the jackrabbit population is not limited by food. Estimated percent consumption of forage energy was 4%, assuming 50% of phytomass was edible, the population density = 100 jackrabbits/km2, metabolizable energy efficiency= 0.4, and the air was calm.

Lepus townsendii Bachman, 1839. J. Acad. Nat. Sei. Phila., 8(l):90. TYPE LOCALITY: U.S.A., Washington, Walla Walla Co., Fort Walla Walla, near present town of Wallula. DISTRIBUTION: S. Alberta to S.W. Ontario (Canada), south to S.W. Wisconsin, C. Kansas, N.C. New Mexico, west to C. Nevada, E.C. California (U.S.A.) and S.C. British Columbia (Canada). ISIS NUMBER: 5301409002002024001., Published as part of James H. Honacki, Kenneth E. Kinman & James W. Koeppl, 1982, Order Lagomorpha, pp. 595-604 in Mammal Species of the World (1 st Edition), Lawrence, Kansas, USA :Alien Press, Inc. & The Association of Systematics Collections on page 601, DOI: 10.5281/zenodo.7353003

The extent, timing, and causes of summer mortality of mule deer (Odocoileus hemionus) fawns were studied in relation to coyote (Canis latrans) population level, alternate prey population levels, and coyote food habits. Additionally, fawn mortality rates were related to supplementary information on vegetation production and fawn hiding cover. A minimum of 90% of summer mortality of fawns was the result of predation by coyotes. Fawn mortality was lowest when microtine rodent populations were high. Mortality rate of fawns was not directly related to population levels of coyotes, deer mice (Peromyscus maniculatus), white-tailed jack rabbits (Lepus townsendii), or Nuttall's cottontails (Sylvilagus nuttallii). Vegetation production and winter snow cover may have been factors regulating microtine populations and thereby fawn mortality rates. Coyote predation can reduce fawn survival in nutritionally healthy deer populations, but alternate prey population levels and cycle phase should be determined by managers prior to decisions about predator control to increase deer populations. J. WILDL. MANAGE. 48(2):489-499 Mule deer populations associated with timbered breaks-badlands habitats in north-central Montana declined sharply during the early 1970's, apparently as a result of extensive overwinter mortality in 1971-72 followed by low fawn production or survival (R. J. Mackie, unpubl. rep., Mont. Dep. Fish and Game, Fed. Aid Proj. W-120-R-7, 1976). Recruitment remained low into the mid-1970's despite apparently favorable habitat conditions. A similar population decline associated with overwinter mortality during 1964-65 was followed by increased fawn production/survival and population recovery within 2 years (Fig. 1). Concomitant with the decline in deer populations, increases in coyote populations were reported in north-central Montana and elsewhere following the 1972 ban on the use of toxicants, especially compound 1080, in predator control. Although quantitative data on coyote population trends in north-central Montana were lacking, studies by C. J. Knowles (unpubl. rep., Mont. Dep. Fish and Game, Fed. Aid Proj. W-120-R-7, 1976) indicated that predation by coyotes on mule deer was occurring in breaks habitat along the Miss uri River and may have been a major factor affecting fawn recruitment. The fact that fawn: doe ratios were low in early winter further indicated that, if predation was the cause of low recruitment, it was especially important during the summer-fall periods. This study was established during the summer of 1976 to quantify the extent, timing, and causes of summer mortality among mule deer fawns; specifically, the role and importance of coyote predation in fawn recruitment to early winter. Intensive studies were conducted annually from early June through mid-September from 1976 through 1981 as one segment of broader studies on the population ecology and habitat relationships of mule deer I Send reprint requests to senior author at Box 5, Montana State University, Bozeman, MT 59717. J. Wildl. Manage. 48(2):1984 489 This content downloaded from 157.55.39.124 on Fri, 13 Jan 2017 18:13:03 UTC All use subject to http://about.jstor.org/terms 490 MULE DEER, COYOTES, AND ALTERNATE PREY * Hamlin et al.

Range changes of mammals in the Great Lakes region (Minnesota, Michigan, Wisconsin, and those parts of Ontario, Ohio, Pennsylvania and New York bordering on the Great Lakes) are described, based on a review of the literature and recent data obtained by the author. Although the Great Lakes and their interconnecting rivers are a marked geographical barrier to the spread of mammals, many changes have taken place in the distribution and abundance of mammals since the last glacial period. These changes are influenced by human activities, climatic changes, and changes in biotic communities. Among these factors, the first one has been most influential. The elk (Cervus canadensis), the bison (Bison bison) and the wolverine (Gulo luscus) have become extinct since the arrival of white man. The cougar (Felis concolor) probably also disappeared, but may have reinvaded the region. Range restrictions have been recorded for the woodland caribou (Rangifer tarandus), Canada lynx (Lynx canadensis), bobcat (Lynx rufus), gray wolf (Canis lupus), black bear (Ursus americanus), marten (Martes americana), fisher (Martes pennanti), and snowshoe hare (Lepus americanus). The latter three species are reinvading formerly occupied ranges during recent years. Range extensions include the majority of species which have exhibited range changes. A distinct northward spread has been recorded for the moose (Alces americana), white-tailed deer (Odocoileus virginianus), opossum (Didelphis marsupialis), eastern cottontail (Sylvilagus floridanus), bobcat (Lynx rufus), raccoon (Procyon lotor), coyote (Canis latrans), gray fox (Urocyon cinereoargenteus), gray squirrel (Sciurus carolinensis), and fox squirrel (Sciurus niger). An eastward spread has been observed for the thirteen-lined ground squirrel (Citellus tridecemlineatus), Franklin ground squirrel (Citellus franklinii) and white-tailed jack rabbit (Lepus townsendii). The smoky shrew (Sorex fumeus) and the yellow-nosed vole (Microtus chrotorrhinus) have apparently displayed a westward spread.