Survival rates of young ungulates have not been studied intensively, but are thought to be more variable than those of adults. Survival rates of young potentially are important factors in the dynamics of populations of mule deer, Odocoileus hemionus, and other large herbivores. We estimated survival among four cohorts of mule deer from birth to 3 years-of-age that inhabited the Sierra Nevada of eastern California. For males and females combined, survival from birth to 6 months was low ((x) over bar = 27.9 +/- 6.8 [SD] %), and differed among cohorts. Annual survival from 6 months to 3 years-of-age was variable (range 80.4 - 90.6%), but survivorship functions did not differ among cohorts. Proportion of mortality of young attributable to predation (55%) was markedly less than reported for adult females elsewhere in the Sierra Nevada (87%), and proportion of mortalities resulting from vehicle collisions (27%) was markedly higher than elsewhere in that range (4%). Our results are consistent with the notion that temporal variation in mortality of young is an important component of variation in the population dynamics of mule deer and beg the question of whether top-down or bottom-up processes regulate populations of those ungulates in arid, unpredictable environments.

Long-term investigations of wild ungulates often dictate that telemetry collars on specific individuals be replaced. We described and evaluated the use of aerial telemetry to facilitate recapture of individual ungulates. Capture of marked animals was much more efficient using fixed-wing telemetry when compared to helicopter telemetry. Total time to capture (P=0.012) and pursuit time (P=0.002) differed significantly, but no difference (P =0.434) in body temperature of mule deer (Odocoileus hemionus) occurred at time of capture. Application of fixed-wing telemetry during net-gun captures of ungulates resulted in greater safety for capture crews and study animals and in potentially substantial monetary savings.

Wildlife Society BulletinVolume 32, Issue 3 p. 987-991 From the Field: Neck lesions in ungulates from collars incorporating satellite technology Paul R. Krausman, Corresponding Author Paul R. Krausman Paul R. Krausman (top, left) is a professor of wildlife at the University of Arizona, Tucson. He has studied desert ungulates since 1972. Paul is a certified wildlife biologist, Southwestern Section representative, and editor of Wildlife Monographs. School of Natural Resources, 325 Biological Sciences East Building, University of Arizona, Tucson, AZ 85721, USA; e-mail for Krausman: [email protected] California Department of Fish and Game, 407 West Live Street, Bishop, CA 93514, USA University Animal Care, The University of Arizona, Tucson, AZ 85721, USA.Search for more papers by this authorVernon C. Bleich, Corresponding Author Vernon C. Bleich James W. Cain III (top, second from left) is a graduate research assistant working towards his Ph.D. in wildlife ecology at the University of Arizona, Tucson. He is studying the habitat relationships of desert bighorn sheep in Cabeza Prieta National Wildlife Refuge, Arizona. He received his B.S. degree in biology from Colorado State University in 1997 and an M.S. degree in Biological conservation from California State University, Sacramento in 2001. School of Natural Resources, 325 Biological Sciences East Building, University of Arizona, Tucson, AZ 85721, USA; e-mail for Krausman: [email protected] California Department of Fish and Game, 407 West Live Street, Bishop, CA 93514, USA University Animal Care, The University of Arizona, Tucson, AZ 85721, USA.Search for more papers by this authorJames W. Cain III, Corresponding Author James W. Cain III Don W. DeYoung (top, third from left) received his D.V.M. from Michigan State University and Ph.D. from Colorado State University. He is a Diplomate from the American College of Veterinary Surgeons. Don has worked at the University of Arizona, Tucson since 1979 and is the Associate Director of University Animal Care and has been involved with numerous studies of wildlife. School of Natural Resources, 325 Biological Sciences East Building, University of Arizona, Tucson, AZ 85721, USA; e-mail for Krausman: [email protected] California Department of Fish and Game, 407 West Live Street, Bishop, CA 93514, USA University Animal Care, The University of Arizona, Tucson, AZ 85721, USA.Search for more papers by this authorThomas R. Stephenson, Corresponding Author Thomas R. Stephenson Brian D. Jansen (top, right) is a graduate research assistant working towards his M.S. degree in wildlife ecology at the University of Arizona, Tucson. He is studying desert bighorn sheep responses to disease and mining in the Silver Bell Mountains, Arizona. He received his B.S. in wildlife from the University of Arizona in 2002. School of Natural Resources, 325 Biological Sciences East Building, University of Arizona, Tucson, AZ 85721, USA; e-mail for Krausman: [email protected] California Department of Fish and Game, 407 West Live Street, Bishop, CA 93514, USA University Animal Care, The University of Arizona, Tucson, AZ 85721, USA.Search for more papers by this authorDon W. DeYoung, Corresponding Author Don W. DeYoung Vernon C. Bleich (bottom, left) received B.S. and M.A. degrees from California State University, Long Beach, and a Ph.D. from the University of Alaska, Fairbanks (UAF). He is a senior environmental scientist with the California Department of Fish and Game (CDFG), where he supervises the Sierra Nevada Bighorn Sheep Recovery Program (SNBSRP) and directs the Round Valley Project, a long-term effort examining relationships between habitat quality, prey densities, and populations of mule deer and mountain sheep in the eastern Sierra Nevada. He has been a Professional Member of the Boone and Crockett Club since 1999, and in 2002 received the Outstanding Alumnus Award from the College of Science, Engineering, and Mathematics at UAF. School of Natural Resources, 325 Biological Sciences East Building, University of Arizona, Tucson, AZ 85721, USA; e-mail for Krausman: [email protected] California Department of Fish and Game, 407 West Live Street, Bishop, CA 93514, USA University Animal Care, The University of Arizona, Tucson, AZ 85721, USA.Search for more papers by this authorPhilip W. McGrath, Corresponding Author Philip W. McGrath Thomas R. Stephenson (bottom, right) received degrees in wildlife biology from Colorado State University (B.S.), Virginia Tech (M.S.), and the University of Idaho (Ph.D.). Tom was Director of the Alaska Department of Fish and Game's Kenai Moose Research Center before joining CDFG, where he is a population biologist assigned to the SNBSRP and concentrates on the restoration of bighorn sheep to historically occupied areas of the Sierra Nevada. School of Natural Resources, 325 Biological Sciences East Building, University of Arizona, Tucson, AZ 85721, USA; e-mail for Krausman: [email protected] California Department of Fish and Game, 407 West Live Street, Bishop, CA 93514, USA University Animal Care, The University of Arizona, Tucson, AZ 85721, USA.Search for more papers by this authorPamela K. Swift, Corresponding Author Pamela K. Swift Philip W. McGrath (not pictured) received his B.S. degree from Saint Joseph's College, Indiana. Currently, he is a contract wildlife biologist working with CDFG primarily on mule deer, sage grouse, and black bears. School of Natural Resources, 325 Biological Sciences East Building, University of Arizona, Tucson, AZ 85721, USA; e-mail for Krausman: [email protected] California Department of Fish and Game, 407 West Live Street, Bishop, CA 93514, USA University Animal Care, The University of Arizona, Tucson, AZ 85721, USA.Search for more papers by this authorBecky M. Pierce, Corresponding Author Becky M. Pierce Pamela K. Swift (not pictured) received her D.V.M. from the University of Bologna (Italy), and was in private practice for 9 years before joining the staff of the CDFG's Wildlife Investigations Lab in 1993. Dr. Swift specializes in diseases of mule deer, black bears, mountain lions, and waterfowl. School of Natural Resources, 325 Biological Sciences East Building, University of Arizona, Tucson, AZ 85721, USA; e-mail for Krausman: [email protected] California Department of Fish and Game, 407 West Live Street, Bishop, CA 93514, USA University Animal Care, The University of Arizona, Tucson, AZ 85721, USA.Search for more papers by this authorBrian D. Jansen, Corresponding Author Brian D. Jansen Becky M. Pierce (bottom, center) is a predator ecologist with the SNBSRP, and advises graduate students as an affiliate assistant professor at UAF. Becky received her M.S. in zoology from the University of Nevada, Reno, and her Ph.D. in wildlife biology from UAF. Her doctoral research focused on mountain lions and mule deer ecology in the eastern Sierra Nevada. School of Natural Resources, 325 Biological Sciences East Building, University of Arizona, Tucson, AZ 85721, USA; e-mail for Krausman: [email protected] California Department of Fish and Game, 407 West Live Street, Bishop, CA 93514, USA University Animal Care, The University of Arizona, Tucson, AZ 85721, USA.Search for more papers by this author Paul R. Krausman, Corresponding Author Paul R. Krausman Paul R. Krausman (top, left) is a professor of wildlife at the University of Arizona, Tucson. He has studied desert ungulates since 1972. Paul is a certified wildlife biologist, Southwestern Section representative, and editor of Wildlife Monographs. School of Natural Resources, 325 Biological Sciences East Building, University of Arizona, Tucson, AZ 85721, USA; e-mail for Krausman: [email protected] California Department of Fish and Game, 407 West Live Street, Bishop, CA 93514, USA University Animal Care, The University of Arizona, Tucson, AZ 85721, USA.Search for more papers by this authorVernon C. Bleich, Corresponding Author Vernon C. Bleich James W. Cain III (top, second from left) is a graduate research assistant working towards his Ph.D. in wildlife ecology at the University of Arizona, Tucson. He is studying the habitat relationships of desert bighorn sheep in Cabeza Prieta National Wildlife Refuge, Arizona. He received his B.S. degree in biology from Colorado State University in 1997 and an M.S. degree in Biological conservation from California State University, Sacramento in 2001. School of Natural Resources, 325 Biological Sciences East Building, University of Arizona, Tucson, AZ 85721, USA; e-mail for Krausman: [email protected] California Department of Fish and Game, 407 West Live Street, Bishop, CA 93514, USA University Animal Care, The University of Arizona, Tucson, AZ 85721, USA.Search for more papers by this authorJames W. Cain III, Corresponding Author James W. Cain III Don W. DeYoung (top, third from left) received his D.V.M. from Michigan State University and Ph.D. from Colorado State University. He is a Diplomate from the American College of Veterinary Surgeons. Don has worked at the University of Arizona, Tucson since 1979 and is the Associate Director of University Animal Care and has been involved with numerous studies of wildlife. School of Natural Resources, 325 Biological Sciences East Building, University of Arizona, Tucson, AZ 85721, USA; e-mail for Krausman: [email protected] California Department of Fish and Game, 407 West Live Street, Bishop, CA 93514, USA University Animal Care, The University of Arizona, Tucson, AZ 85721, USA.Search for more papers by this authorThomas R. Stephenson, Corresponding Author Thomas R. Stephenson Brian D. Jansen (top, right) is a graduate research assistant working towards his M.S. degree in wildlife ecology at the University of Arizona, Tucson. He is studying desert bighorn sheep responses to disease and mining in the Silver Bell Mountains, Arizona. He received his B.S. in wildlife from the University of Arizona in 2002. School of Natural Resources, 325 Biological Sciences East Building, University of Arizona, Tucson, AZ 85721, USA; e-mail for Krausman: [email protected] California Department of Fish and Game, 407 West Live Street, Bishop, CA 93514, USA University Animal Care, The University of Arizona, Tucson, AZ 85721, USA.Search for more papers by this authorDon W. DeYoung, Corresponding Author Don W. DeYoung Vernon C. Bleich (bottom, left) received B.S. and M.A. degrees from California State University, Long Beach, and a Ph.D. from the University of Alaska, Fairbanks (UAF). He is a senior environmental scientist with the California Department of Fish and Game (CDFG), where he supervises the Sierra Nevada Bighorn Sheep Recovery Program (SNBSRP) and directs the Round Valley Project, a long-term effort examining relationships between habitat quality, prey densities, and populations of mule deer and mountain sheep in the eastern Sierra Nevada. He has been a Professional Member of the Boone and Crockett Club since 1999, and in 2002 received the Outstanding Alumnus Award from the College of Science, Engineering, and Mathematics at UAF. School of Natural Resources, 325 Biological Sciences East Building, University of Arizona, Tucson, AZ 85721, USA; e-mail for Krausman: [email protected] California Department of Fish and Game, 407 West Live Street, Bishop, CA 93514, USA University Animal Care, The University of Arizona, Tucson, AZ 85721, USA.Search for more papers by this authorPhilip W. McGrath, Corresponding Author Philip W. McGrath Thomas R. Stephenson (bottom, right) received degrees in wildlife biology from Colorado State University (B.S.), Virginia Tech (M.S.), and the University of Idaho (Ph.D.). Tom was Director of the Alaska Department of Fish and Game's Kenai Moose Research Center before joining CDFG, where he is a population biologist assigned to the SNBSRP and concentrates on the restoration of bighorn sheep to historically occupied areas of the Sierra Nevada. School of Natural Resources, 325 Biological Sciences East Building, University of Arizona, Tucson, AZ 85721, USA; e-mail for Krausman: [email protected] California Department of Fish and Game, 407 West Live Street, Bishop, CA 93514, USA University Animal Care, The University of Arizona, Tucson, AZ 85721, USA.Search for more papers by this authorPamela K. Swift, Corresponding Author Pamela K. Swift Philip W. McGrath (not pictured) received his B.S. degree from Saint Joseph's College, Indiana. Currently, he is a contract wildlife biologist working with CDFG primarily on mule deer, sage grouse, and black bears. School of Natural Resources, 325 Biological Sciences East Building, University of Arizona, Tucson, AZ 85721, USA; e-mail for Krausman: [email protected] California Department of Fish and Game, 407 West Live Street, Bishop, CA 93514, USA University Animal Care, The University of Arizona, Tucson, AZ 85721, USA.Search for more papers by this authorBecky M. Pierce, Corresponding Author Becky M. Pierce Pamela K. Swift (not pictured) received her D.V.M. from the University of Bologna (Italy), and was in private practice for 9 years before joining the staff of the CDFG's Wildlife Investigations Lab in 1993. Dr. Swift specializes in diseases of mule deer, black bears, mountain lions, and waterfowl. School of Natural Resources, 325 Biological Sciences East Building, University of Arizona, Tucson, AZ 85721, USA; e-mail for Krausman: [email protected] California Department of Fish and Game, 407 West Live Street, Bishop, CA 93514, USA University Animal Care, The University of Arizona, Tucson, AZ 85721, USA.Search for more papers by this authorBrian D. Jansen, Corresponding Author Brian D. Jansen Becky M. Pierce (bottom, center) is a predator ecologist with the SNBSRP, and advises graduate students as an affiliate assistant professor at UAF. Becky received her M.S. in zoology from the University of Nevada, Reno, and her Ph.D. in wildlife biology from UAF. Her doctoral research focused on mountain lions and mule deer ecology in the eastern Sierra Nevada. School of Natural Resources, 325 Biological Sciences East Building, University of Arizona, Tucson, AZ 85721, USA; e-mail for Krausman: [email protected] California Department of Fish and Game, 407 West Live Street, Bishop, CA 93514, USA University Animal Care, The University of Arizona, Tucson, AZ 85721, USA.Search for more papers by this author First published: 02 April 2019 https://doi.org/10.2193/0091-7648(2004)032[0987:FTFNLI]2.0.CO;2Citations: 24 AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinkedInRedditWechat Literature cited Bleich, V. C., R. T. Bowyer, A. M. Pauli, M. C. Nicholson, and R. W. Anthes. 1994. Mountain sheep Ovis canadensis and helicopter surveys: ramifications for the conservation of large mammals. Biological Conservation 70: 1–7. Bleich, V. C., and B. M. Pierce. 1999. Expandable and economical long-term collars for juvenile mule deer. California Fish and Game 85: 56–62. Bleich, V. C., T. R. Stephenson, N. J. Holste, I. C. Snyder, J. P. Marshal, P. W. McGrath, and B. M. Pierce. 2003. Effects of tooth extraction on selected biological parameters of female mule deer. Wildlife Society Bulletin 31: 233–236. Bleich, V. C., J. D. Wehausen, J. A. Keay, and J. G. Stahmann. 1980. Radio telemetry collars and mountain sheep: a cautionary note. Desert Bighorn Council Transactions 34: 6–8. Carter, G. R., M. M. Chengappa, A. W. Roberts, G. W. Claus, and Y. Rikihisa. 1995. Essentials of veterinary microbiology. Fifth edition. Williams and Wilkins, Baltimore, Maryland, USA. Carter, G. R., and J. R. Cole, Jr. 1990. Diagnostic procedures in veterinary bacteriology and mycology. Fifth edition. Academic Press, New York, New York, USA. Committee on Acceptable Field Methods. 1987. Acceptable field methods in mammalogy. Journal of Mammalogy 68 (supplement): 1–18. Fancy, S. T., L. F. Pank, D. C. Douglas, C. H. Curby, G. W. Garner, S. C. Amstrup, and W. L. Regelin. 1988. Satellite telemetry: a new tool for wildlife research and management. United States Department of Interior, Fish and Wildlife Service Resource Publication 172. Godfrey, J. D., D. M. Bryant, and M. J. Williams. 2003. Radiotelemetry increases free-living energy costs in the endangered Takahe Porphyrio mantelli. Biological Conservation 114: 35–38. McCutchen, H. E. 1990. A technique to visually assess physical condition of bighorn sheep. Desert Bighorn Council Transactions 29: 27–28. Mourão, G., and Í. M. Merdi. 2002. A new way of using inexpensive large-scale assembled GPS to monitor giant anteaters in short time intervals. Wildlife Society Bulletin 30: 1029–1032. Pierce, B. M., V. C. Bleich, and R. T. Bowyer. 2000a. Social organization of mountain lions: does a land-tenure system regulate population size Ecology 81: 1533–1543. Pierce, B. M., V. C. Bleich, and R. T. Bowyer. 2000b. Selection of mule deer by mountain lions and coyotes: effects of hunting style, body size, and reproductive status. Journal of Mammalogy 81: 462–472. Powell, R. A., and G. Proulx. 2003. Trapping and marking terrestrial mammals for research: integrating ethics, performance criteria, techniques, and common sense. Institute for Laboratory Animal Research Journal 44: 259–276. Schaefer, R. J., S. G. Torres, and V. C. Bleich. 2000. Survivorship and cause-specific mortality in sympatric populations of mountain sheep and mule deer. California Fish and Game 86: 127–135. Schmidt, R. H., and J. G. Bruner. 1981. A professional attitude toward humaneness. Wildlife Society Bulletin 9: 289–291. Smith, B. L., W. P. Burger, and F. J. Singer. 1998. An expandable radiocollar for elk calves. Wildlife Society Bulletin 26: 113–117. White, G. C., and R. A. Garrott. 1990. Analysis of wildlife radiotracking data. Academic Press, New York, New York, USA. Citing Literature Volume32, Issue3September 2004Pages 987-991 ReferencesRelatedInformation

Risk of predation may affect individuals in prey populations by limiting their use of high-quality habitat. Predation risk, however, cannot be implicated as a factor in habitat selection by prey without data comparing quality of selected and avoided habitats, along with the predation risk associated with those habitats. If forage benefits and predation risk are not positively correlated among habitat types, then predation risk may have little influence on the habitat selected by prey. We evaluated habitat selection by mountain lions (Puma concolor) and mule deer (Odocoileus hemionus) in the eastern Sierra Nevada, California, USA, from 1994 to 1997, to determine how forage benefit or risk of predation by mountain lions affects habitat selection by mule deer. Mountain lions were the primary predator of mule deer in our study area. Stands of bitterbrush (Purshia tridentata) in the Great Basin provided more cover for mule deer than surrounding patches of rabbitbrush (Chrysothamnus nauseosum) or desert peach (Prunus andersonii). Bitterbrush also was important forage for mule deer during winter. We hypothesized that mountain lions would be more successful at stalking and killing mule deer in habitats with more concealment cover than in habitats with less cover, and therefore mule deer would choose between foraging on bitterbush and avoiding predation by mountain lions. We collected data on habitat characteristics in 3 types of locations: random locations (n = 180), deer foraging locations (n = 179), and locations where mountain lions killed deer (n = 41). Mule deer selected habitat at greater elevations (P < 0.001) with more bitterbrush (P < 0.001) and less rabbitbrush (P = 0.033) when compared with random locations. Logistic regression indicated that mountain lions killed deer in relatively open areas with more desert Peach (P < 0.001) than at locations in which deer foraged. Therefore, deer were not confronted with a trade-off when selecting habitat on winter range, and they minimized the ratio of predation risk to forage benefit by selecting habitat with more bitterbrush. Changes in diet among seasons, which occur for herds of migratory deer, lead to individuals experiencing changing predation risk to forage benefit ratios throughout the year. Hence, migratory populations of mule deer likely adopt different strategies of habitat selection among seasons.

Estimating size ofanimal populations is im­ portant for effective management and conser~ vation. Mountain lions (Puma concolor) have proven especially difficult to enumerate (Ander~

The removal of an incisiform tooth to determine age in live cervids has generated disagreement among wildlife professionals, but few data are available to resolve whether or not study animals are affected by that technique. We found no effect of tooth removal on body mass, percent body fat, pregnancy rate, or fetal rate among mule deer (Odocoileus hemionus) inhabiting a Great Basin winter range. Results from a population of deer in the Sonoran Desert were similar. This information is provided to assist others contemplating tooth removal as a method to determine age in cervids and to help resolve the current controversy.

measuring fat dynamics is extremely important in understanding the nutritional ecology of cervids. Estimates of body composition provide insight into an animal's energetic state, potential for reproduction and survival, and quality of habitat they occupy. We validated accuracy of in vivo and post-mortem indices to predict total body fat in mule deer (Odocoileus hemionus). Rump fat thickness measured using ultrasonography was related linearly to ingesta-free body fat, but disappeared at similar to5.6% body fat. Loin muscle thickness determined by ultrasonography and condition scores exhibited potential to quantify nutritional reserves when rump fat has been depleted. Whole body mass did not predict body fat in adult females, but was a good predictor of ingesta-free lean body mass. Kidney fat mass and kidney fat index were moderate predictors of total body fat, but the relationship was curvilinear. Of the post-mortem indices we tested, the Kistner Score exhibited the strongest linear relationship to ingesta-free body fat. We suggest that using an accurate in vivo method to assess nutritional reserves reveals much about past nutritional history and future productivity of individuals within a population, especially when determined repeatedly in radiocollared animals.

We assessed antler size of Alaskan moose (A lees a/ces gigas) with respect to the geographic region and dominant vegetation community (taiga or tundra) from which they were harvested from 1968 to 1983. Our retrospective analysis indicated that moose from the Copper River Delta and Alaska Peninsula possessed the largest antlers, whereas those from southeast Alaska, USA, had the smallest antlers. Delta flood plains of the Copper River offer a rich food supply for moose, and browse on the Alaska Peninsula also is plentiful; both areas have mild maritime climates and longer growing seasons than tundra and taiga habitats in interior Alaska-large antlers in those moose populations likely were the result of superior nutrition. After controlling for age, antlers of moose from tundra communities were significantly larger than those inhabiting taiga. Willows (Salix spp.), which are an important food for moose, dominate braided rivers and associated riparian areas in tundra habitat, and provide a high-quality and stable food supply over time. Fire and subsequent successional changes dominate taiga landscapes, which results in a variable food supply that is sometimes low in quality and quantity. Again, forage abundance and quality likely play important roles in determining antler size for populations of Alaskan moose inhabiting those plant communities. Nonetheless, antlers of A. a. gigas from taiga regions in Alaska, USA, were larger than those of A. a. andersoni from similar habitat in northeastern Minnesota, USA, and Saskatchewan, Canada. In addition, moose from tundra habitat on the Seward Peninsula, Alaska, which have colonized that area within the last 30 years from the boreal forest, possessed antlers intermediate in size between moose inhabiting taiga and tundra. Moreover, moose from forested areas of southeast Alaska, which have a unique mitochrondial DNA haplotype from other subspecies of moose, also had comparatively smaller antlers than other moose in Alaska. Those outcomes indicated that differences in antler size likely have a genetic in addition to a nutritional basis. We hypothesize that differences in antler size of Alaskan moose in relation to habi tat may have genetic as well as nutritional underpinnings related to openness of habitat, but more research is needed. Finally, our results on antler morphology, in concert with information on pelage coloration and recent data on genetics, do not support hypotheses concerning a double migration, or eastern and western races of moose, forwarded to explain morphological variation in moose inhabiting the New World. Likewise, we reject the hypothesis that ecotypical differences are primarily responsible for morphological variation in subspecies of moose inhabi ting North America. ALCES VOL. 38: 155-165 (2002)

We studied effects of mechanical crushing on abundance of forage and quality of feltleaf willow (Salix alaxensis) in winter, 3 years following habitat manipulation in interior Alaska, USA. We also examined differences in snow depth and track counts for Alaskan moose (Alces alces gigas) between the crushed site and an adjacent area containing old-growth stands of willow. Likewise we tested for differences in foraging by moose between areas, and noted differences in use of the 2 sites by adult males, and females and their young. Mechanical crushing resulted in a 5-fold increase in the number of leaders of current annual growth and a 3-fold increase in dry mass for willows subjected to crushing compared with the uncrushed site. The size of individual leaders of feltleaf willow did not differ between sites, probably because the growth form of leaders resprouting from the crushed area was similar to stump sprouts available to moose on the uncrushed area. Moose took larger bites, however, on the crushed compared with the uncrushed site. No significant differences occurred in the chemical composition of willows, including concentration of tannins, between crushed and uncrushed areas. Similarly, there were no differences in in vitro dry matter digestibility of willows between sites. Moose sexually segregated in winter. Males occurred predominantly on the more open crushed area, whereas females and young used the uncrushed area where the dense vegetation offered substantial concealment cover. We hypothesized that mechanical manipulation of willows benefited primarily male moose 3 years following crushing, and that females and young faced a tradeoff between feeding on the greater abundance of forage on the crushed area and a reduced risk of predation on the uncrushed site. We see merits in considering the sexes of moose as if they were separate species for purposes of management, and recommend that future management of habitat to benefit moose consider differences in requirements of the sexes, especially factors related to risk of predation.

Predation on mule deer (Odocoileus hemionus) by mountain lions (Puma concolor) and coyotes (Canis latrans) was examined to test effects of hunting style and body size, and for mountain lions reproductive status, on selection of prey. Mountain lions, which hunt by stalking, selected Ii-year-old mule deer as prey. Body condition of mule deer did not affect prey selection by coyotes or mountain lions, and both predators preyed upon females and older adult deer more often than expected based on the percentage of these groups in the population. Female mountain lions selected female deer, but male mountain lions did not. Female mountain lions without offspring, however, did not differ from male mountain lions in prey selection. Coyotes did not select for young deer. Female mountain lions with kittens were selective for young deer in late summer.

Mountain lions (Puma concolor) are thought to regulate their populations via social behavior. The proposed mechanism is a land-tenure system that results in exclusion of individuals from the population through territoriality and temporal avoidance. In the absence of mortality from intraspecific aggression, social behavior can regulate a population only by limiting reproduction. Successful reproduction among large mammals is related to the availability of food. Four states of nature must hold if a population is regulated by social behavior via a land-tenure system in mountain lions: (1) individuals should not be distributed randomly, but each should have its own distinct distribution, and those individuals should maintain regions of exclusivity; (2) use of food within the distribution of an individual should not be random, but should be clumped as individuals try to exclude each other from access to prey; (3) those clumps of prey must not be simply the result of prey distribution, but of social interactions among lions; and (4) social interactions and defense of food should occur in regions where distributions of individuals overlap; therefore, prey use by individual lions in areas of overlap should be less than expected based on the distribution of prey. We tested hypotheses regarding social regulation for a population of mountain lions that co-occurred on a winter range with a population of mule deer (Odocoileus hemionus) in the eastern Sierra Nevada, California, from 1991 to 1997. Individual mountain lions (n = 10) exhibited distinct distributions, and deer killed by individuals (n = 112) were not distributed randomly within the distribution of the lion that did the killing. Furthermore, the nonrandom distribution of lion-killed deer could be explained by the distribution of live deer alone, but that result was marginally not significant (P = 0.06) and indicated that something else affected the locations of kills made by lions. Results from tests of whether the presence of another mountain lion affected where individuals chose to kill prey indicated that social interactions had no effect. The distribution of deer killed by individual mountain lions in areas of exclusive use and areas of overlap was identical to that expected based on the distribution of live deer alone. That outcome indicated social behavior was not regulating the population of mountain lions via partitioning of prey, and temporal differences in use of space could not explain the distribution of mountain lions we observed. A system of land-tenure and mutual avoidance did not limit the population of mountain lions in Round Valley via partitioning of prey. Our results are concordant with other studies of large mammalian carnivores, which reported that populations were not limited primarily by territoriality but by the supply of food.

This study refines a method reported by Smallwood and Fitzhugh (Smallwood, K.S., Fitzhugh, E.L., 1993. A rigorous technique for identifying individual mountain lions Felis concolor by their tracks. Biological Conservation 65, 51–59) that attempted to discriminate between individual mountain lions by certain measurements of their tracks in the field. During the months of January–March 1996, we followed 10 radio-collared mountain lions in the Sierra Nevada of California and obtained photographs of their tracks in the soil and snow under many different environmental conditions. Linear and area measurements were determined from track photographs and Fisher’s discriminant analysis was used to differentiate between each track set. Unlike the Smallwood and Fitzhugh analysis, we were certain about the identity of most of the mountain lions that made tracks. Our results indicate that track sets had both correct and incorrect “groupings” and that these groupings were sensitive to the type of substrate in which a track set was found, the time of day it was photographed, and the number of tracks in a set. In general, it is important to minimize variation associated with substrate and time of day between track sets and to concentrate on sets that contain three or more tracks. This technique has potential application in wildlife conservation; however, the cautionary guidelines, developed in this paper, should be considered.

We studied movements of mountain lions (Puma concolor) in the southern Sierra Nevada of California from 1992-1997. We observed two distinct patterns, which likely represent strategies of mountain lions for coping with variability in abundance of their primary prey, mule deer (Odocoileus hemionus). Some mountain lions migrated together, often slowly, following movements of mule deer from winter range toward the summer range of their prey. Those mountain lions remained together on the eastern scarp of the Sierra Nevada and overlapped in distribution throughout the year. Other mountain lions exhibited rapid movements to disjunct summer ranges, on the western side of the Sierra Nevada, shared with mountain Lions that did not occur on their winter range. Mountain lions that moved more slowly and overlapped in distribution had large annual home ranges (95% adaptive kernel; (X) over bar = 817 km(2)), whereas mountain lions with distinct summer ((X) over bar = 425 km(2)) and winter ((X) over bar = 476 km(2)) distributions had smaller home ranges. Such disparate patterns of movement may lead to difficulties in sampling population size for mountains lions. Moreover, maintaining corridors that would allow for both patterns of movement may be critical for the conservation of these large felids. Finally, extensive overlap in the distribution of mountain lions, especially the association of one group of individuals on winter range and another on summer range for mountain lions with disjunct distributions, indicates a more flexible social system than previously described.

We adapted the expandable collars used by others on young mouflon sheep, Ovis musimon, for use on juvenile mule deer, Odocoileus hemionus. We used these collars to investigate survivorship and cause-specific mortality among these cervids during 1994-1998. The collars were economical and simple to construct, and retention rate among 109 juvenile mule deer was >98%. Even after 2.5 years, no collars appeared to fit too tightly and we observed no evidence of injury to animals. These collars offer a dependable and economical alternative to expensive, factory-made, expandable collars.

Onset of feeding by mountain lions (Puma concolor) on individual prey was studied with an automatic camera near mule deer (Odocoileus hemionus) that had been killed and cached by mountain Lions. We categorized mountain lions as adult males, adult females, females with juveniles, and females with kittens. After sunset, females with kittens returned to kills significantly earlier than males, females, or females with juveniles. Early feeding by females with kittens might reflect avoidance of conspecifics, which are known to kill kittens. Alternatively, mothers with young kittens may remain closer to caches of prey than lone males, females, or mothers with juveniles. Increased energetic needs of lactating mothers also may dictate earlier feeding.

-We used radiotelcmehY and searched with a trained hound to locate the dens of 3 recently parturient mountain lions (Felis cnncolor). "J11ese dens were located in dense riparian vegetation along the same stream in the bottom of a steep canyon. We monitored the circadian temperatures of 2 dens at I-h intervals and compared them to ambient temperatures recorded simultaneously. We found mountain lion dens to effectively moderate high ambient temperatures, but these dens failed ta provide a thermal advantage at the lowest ambient temperatures recorded in this investigation. We conclude that mountain lion dens provide effective protection from thermal maxima for young, immobile kittens. Key wonk Felis concalor, mountain lion, temperature, California, den, behavior. Female mountain lions (Felis concolor) select protected locations in which to bear young (Shaw 1989:7, Beier et al. 1995), but little information is available on den site characteristics for this elusive felid. Here, we describe some characteristics of 3 dens used by different females and their litters and quantify the thermal characteristics of 2 of those dens. DESCRIPTION OF STUDY AREA Our study area is located in Mono Co., California, approximately 35 km NW of Bishop (118°25'\V, 37°20'N), Inyo Co., California. This area is on the western edge of the Great Basin, immediately east of the crest of the Sierra Nevada. The dominant vegetation type in the general area is sagebrush (Artemisia tridentata) scrub with pinyon pine (Pinus monophylla) forest at higher elevations. Dense vegetation, dominated by willows (Salix spp.) and wild rose (Rosa spp.), occurs along the major water courses.