Table of Contents Ursus 5           

Bacon, Ellis S. and Burghardt, Gordon M. Food preference testing of captive black bears. 1983. International Conf. Bear Res. and Manage. 5, 102-105 ->

Beecham, John J., Reynolds, Doyle G., and Hornocker, Maurice G. Black bear denning activities and den characteristics in west-central Idaho. 1983. International Conf. Bear Res. and Manage 5, 79-86 ->

Blanchard, Bonnie M. Grizzly bear--habitat relationships in the Yellowstone area. 1983. International Conf. Bear Res. and Manage. 5, 118-123 ->

Bunnell, Fred L. and Hamilton, Tony. Forage digestibility and fitness in grizzly bears. 1983. International Conf. Bear Res. and Manage. 5, 179-185 ->

Burst, Tom L. and Pelton, Michael R. Black bear mark trees in the Smoky Mountains. 1983. International Conf. Bear Res. and Manage. 5, 45-53 ->

Cushing, Bruce S. Responses of polar bears to human menstrual odors. 1983. International Conf. Bear Res. and Manage. 5, 270-274 ->

DeMaster, Douglas P. and Stirling, Ian. The estimation of survival and litter size of polar bear cubs. 1983. International Conf. Bear Res. and Manage. 5, 260-263 ->

Eagle, Thomas C. and Pelton, Michael R. Seasonal nutrition of black bears in the Great Smoky Mountains National Park. 1983. International Conf. Bear Res. and Manage. 5, 94-101 ->

Garshelis, David L., Quigley, Howard B., Villarrubia, Charles R., and Pelton, Michael R. Diel movements of black bears in the southern Appalachians. 1983. International Conf. Bear Res. and Manage. 5, 11-19 ->

Graber, David M. and White, Marshall. Black bear food habits in Yosemite National Park. 1983. International Conf. Bear Res. and Manage. 5, 1-10 ->

Hansson, Rasmus and Thomassen, Jorn. Behavior of polar bears with cubs in the denning area. 1983. International Conf. Bear Res. and Manage. 5, 246-254 ->

Herrero, Stephen. Social behaviour of black bears at a garbage dump in Jasper National Park.1983. International Conf. Bear Res. and Manage. 5, 54-70 ->

Hoak, John H., Clark, Tim W., and Weaver, John L. Of grizzly bears and commercial outfitters in Bridger-Teton National Forest, Wyoming. 1983. International Conf. Bear Res. and Manage. 5, 110-117 ->

Jorgenson, Carole J. Bear-sheep interactions, Targhee National Forest. 1983. International Conf. Bear Res. and Manage. 5, 191-200 ->

Keay, Jeffrey A. and Van Wagtendonk, Jan W. Effect of Yosemite backcountry use levels on incidents with black bears. 1983. International Conf. Bear Res. and Manage. 5, 307-311 ->

Kendall, Katherine C. Use of pine nuts by grizzly and black bears in Yellowstone National Park. 1983. International Conf. Bear Res. and Manage. 5, 166-173 ->

Kingsley, M. C. S., Nagy, J. A., and Russell, R. H. Patterns of weight gain and loss for grizzly bears in Northern Canada. 1983. International Conf. Bear Res. and Manage. 5, 174-178 ->

Knight, Richard R. and Judd, Steven L. Grizzly bears that kill livestock. 1983. International Conf. Bear Res. and Manage. 5, 186-190 ->

Kolenosky, George B. and Prevett, J. Paul. Productivity and maternity denning of polar bears in Ontario. 1983. International Conf. Bear Res. and Manage. 5, 238-245 ->

Larsen, Thor, Jonkel, Charles, and Vibe, Christian. Satellite radio-tracking of polar bears between Svalbard and Greenland. 1983. International Conf. Bear Res. and Manage. 5, 230-237 ->

LeCount, Albert L. Denning ecology of black bears in central Arizona. 1983. International Conf.Bear Res. and Manage. 5, 71-78 ->

Lindzey, James S., Alt, Gary L., McLaughlin, Craig R., and Kordek, Walter S. Population response of Pennsylvania black bears to hunting. 1983. International Conf. Bear Res. and Manage. 5, 34-39 ->

Manville, Albert M. Human impact on the black bear in Michigan's Lower Peninsula. 1983. International Conf. Bear Res. and Manage.  5, 20-33 ->

Martin, P. Factors influencing globe huckleberry fruit production in Northwestern Montana. 1983. International Conf. Bear Res. and Manage. 5, 159-165 ->

Martin, Sandra K. and Jonkel, Charles J. Use of sea ice habitat by polar bears. 1983. International Conf. Bear Res. and Manage. 5, 255-259 ->

McArthur Jope, Katherine L. Habituation of grizzly bears to people:  a hypothesis. 1983. International Conf. Bear Res. and Manage. 5, 322-327 ->

Meagher, Mary and Phillips, Jerry R. Restoration of natural populations of grizzly and black bears in Yellowstone National Park. 1983. International Conf. Bear Res. and Manage. 5, 152-158 ->

Miller, Gary D. Responses of captive grizzly and polar bears to potential repellents. 1983. International Conf. Bear Res. and Manage. 5, 275-279 ->

Mysterud, Ivar. Characteristics of summer beds of European brown bears in Norway. 1983. International Conf. Bear Res. and Manage. 5, 208-222 ->

Nelson, Ralph A., Folk, G. Edgar Jr., Pfeiffer, Egbert W., Craighead, John J., Jonkel, Charles J., and Steiger, Dianne L. Behavior, biochemistry, and hibernation in black, grizzly, and polarbears. 1983. International Conf. Bear Res. and Manage. 5, 284-290 ->

Nozaki, Eikichi, Azuma, Shigeru, Aoi, Toshiki, Torii, Harumi, Ito, Tetsuro, and Maeda, Kishio. Food habits of Japanese black bear. 1983. International Conf. Bear Res. and Manage. 5, 106-109 ->

O'Pezio, John, Clarke, Stephen H., and Hackford, Charles. Chronology of black bear denning in the Catskill Region of New York. 1983. International Conf. Bear Res. and Manage. 5, 87-93 ->

Palumbo, P. J., Wellik, Dianne L., Bagley, Nancy A., and Nelson, Ralph A. Insulin and glucagon responses in the hibernating black bear. 1983. International Conf. Bear Res. and Manage. 5, 291-296 ->

Roth, Hans U. Diel activity of a remnant population of European brown bears. 1983. International Conf. Bear Res. and Manage. 5, 223-229 ->

Schwartz, Charles C. and Franzmann, Albert W. Effects of tree crushing on black bear predation on moose calves. 1983. International Conf. Bear Res. and Manage. 5, 40-44 ->

Servheen, Christopher and Klaver, Robert. Grizzly bear dens and denning activity in the Mission and Rattlesnake Mountains, Montana. 1983. International Conf. Bear Res. and Manage. 5, 201-207 ->

Shaffer, Mark L. Determining minimum viable population sizes for the grizzly bear. 1983. International Conf. Bear Res. and Manage. 5, 133-139 ->

Smith, Jane Kapler. BIMS--the bear reporting network for the National Park Service. 1983. International Conf. Bear Res. and Manage. 5, 297-301 ->

Stringham, Stephen F. Roles of adult males in grizzly bear population biology. 1983. International Conf. Bear Res. and Manage. 5, 140-151 ->

Tate, Jane and Pelton, Michael R. Human-bear interactions in Great Smoky Mountains National Park. 1983. International Conf. Bear Res. and Manage. 5, 312-321 ->

Williamson, James F. Jr. and Whelan, James B. Computer-assisted habitat mapping for black bear management in Shenandoah National Park. 1983. International Conf. Bear Res. and Manage. 5, 302-306 ->

Wooldridge, Donald R. Polar bear electronic deterrent and detection systems. 1983. International Conf. Bear Res. and Manage. 5, 264-269 ->

Worley, David E., Greer, Kenneth R., and Palmisciano, Dan. Possible relationships between trichinellosis and abnormal behavior in bears. 1983. International Conf. Bear Res. and Manage. 5, 280-283 ->

Zager, Peter, Jonkel, Charles, and Habeck, James. Logging and wildfire influence on grizzly bear habitat in Northwestern Montana. 1983. International Conf. Bear Res. and Manage. 5, 124-132 ->

Abstracts

Bacon, Ellis S. and Burghardt, Gordon M. Food preference testing of captive black bears.  1983. International Conf. Bear Res. and Manage. 5, 102-105

Abstract: A method was developed to test food preferences of 2 young captive female black bears (Ursus americanus) under controlled conditions.  Two sets of food items  (5 native and 7 non-native) were tested biweekly for 1 year in a seminatural enclosure in Tennessee.  The bears exhibited definite preferences among both sets of foods.  The preferences were significantly correlated between the bears and were consistent throughout the year.  In the native food test, acorns (Quercus alba) were the most preferred.  In the non-native food test, ish (Ictiobus sp.) was the most preferred food.  The foods most highly preferred were rich in either protein or carbohydrates.

Beecham, John J., Reynolds, Doyle G., and Hornocker, Maurice G. Black bear denning activities and den characteristics in west-central Idaho.  1983. International Conf. Bear Res. and Manage 5, 79-86

Abstract: Denning activities and den characteristics of black bears (Ursus americanus) were studied in west-central Idaho during 1973-77.  Den entry and emergence varied among bears and years, and the denning season extended from mid-October until mid-April.  Thirty-one radio-instrumented bears were handled 83 times in 65 different dens.  Forty-seven (72%) of the 65 dens were ground dens excavated into a hillside or under the base of a tree, stump, or shrub.  Thirteen (20%) dens were located in the base of hollow trees and 5 (8%) in hollow logs or rock cavities.  Bears denned at various elevations, slopes, and aspects, and under a variety of canopy coverages, but some selection for snow and vegetative cover characteristics at different elevations and aspects was noted.  No significant differences in den dimensions were noted for specific sex or age classes of bears, except that adult males dug larger entrances (P<0.05) than other bears.  Four instances of den reuse were observed. 

Blanchard, Bonnie M. Grizzly bear--habitat relationships in the Yellowstone area.  1983. International Conf. Bear Res. and Manage. 5, 118-123

Abstract: Habitat use by grizzly bears (Ursus arctos) was studied from 1977 through 1979 in a 20,000 km² area with Yellowstone National Park in the center.  Of 1826 aerial radio locations of 46 instrumented grizzlies, 90% were in timber.  Three fourths of the locations were 100 m or less from an edge between timber and an opening.  Timber over 3 m tall with canopy cover of 26-75% accounted for 50% of all activity sites from March through November.  The Abies lasiocarpal/Vaccinium scoparium community alone contained 23% of the total activity sites and 35% of the forested activity sites.  Of 507 observations of feeding activity, 45% were recorded in timber over 3 m tall with a canopy cover of 26-100%, 34% in timber with a 0.1-25% canopy cover, 20% in open habitats, and 3% in timber less than 3 m tall.  Ninety-nine percent of examined day beds were in forested communities.

Bunnell, Fred L. and Hamilton, Tony. Forage digestibility and fitness in grizzly bears.  1983. International Conf. Bear Res. and Manage. 5, 179-185

Abstract: Abilities to digest dry matter, crude protein, and gross energy were evaluated for 2 captive grizzly bears (Ursus arctos) in 1977 and 1978.  Four diets were used: 1 basal (horsemeat plus dog chow), 2 incorporating natural foodstuffs (blueberries and salmon), and 1 containing high fiber (beet pulp).  Average apparent digestibilities (% dry weight) for the horsemeat plus dog chow, blueberry, and salmon diets were 82% (dry matter), 90.2% (crude protein), and 88.1% (gross energy).  Relative digestibilities of specific foodstuffs in decscending order were: blueberries, salmon, and beet pulp.  Addition of beet pulp to the diet reduced measured digestibilities to: 48.7% (dry matter), 75.1% (crude protein), and 62.0% (gross energy).  Grizzly bears feeding on horsemeat exhibited digestibilities similar to those reported for obligate carnivores.  Although U. arctos has evolved omnivorous food habits and morphological adaptations for herbivory, it digests cellulose poorly but has apparently conserved the ability to digest meat efficiently.  The ability to digest high quality forage rapidly is presumably a necessary concomitant of denning. 

Burst, Tom L. and Pelton, Michael R. Black bear mark trees in the Smoky Mountains.  1983. International Conf. Bear Res. and Manage. 5, 45-53

Abstract: A total of 691 black bear (Ursus americanus) mark trees were located in the Great Smoky Mountains National Park.  Mark trees along preselected index trails were tagged, physiognomic parameters around the trees measured, and characteristics of the tree and mark recorded.  Trees along the index trails were reobserved periodically from April to December 1976-77 (bi-weekly between May and October) to monitor fresh marking.  Eight different coniferous and 26 different hardwood species were marked; the choice of species apparently reflects their availability in areas of high bear use.  Mark trees were located primarily along abandoned trails and ridge tops.  Most fresh marking occurred during May, June, and July.  Thirty-one percent and 23% of the mark trees along index routes exhibited fresh marks during 1976 and 1977, respectively.  Reduction of aggression may not be the only function of marking.  The incidence of fresh marking may be useful as an index to population density. 

Cushing, Bruce S. Responses of polar bears to human menstrual odors.  1983. International Conf. Bear Res. and Manage. 5, 270-274

Abstract: Laboratory and field tests were conducted at Churchill, Manitoba, in 1978 and 1979 to determine whether human menstrual odors attract polar bears (Ursus maritimus).  The polar bear was chosen because the odor of its primary prey, seals, could be used as a standard attractant against which the relative attractiveness of other scents could be measured.  When 4 captive bears were presented with a series of different odors a strong behavioral response was elicited only by seal scents and menstrual odors (used tampons).  When these materials were arrayed in a location frequented by free-ranging bears, the bears detected and consumed, the food scent samples and used tampons, but ignored the non-food scents and human blood.  The primary method of detection was by scent with a minority of samples being detected visually or by other means.  The lack of response to the other scents, combined with the fact that in the laboratory and field the bears' responses to seal scents demonstrated that menstrual odors attract polar bears.  Comparing bears responses to human blood and menstrual blood indicates that it is not the blood that is acting as the attractant, but some property peculiar to the menstrual products.

DeMaster, Douglas P. and Stirling, Ian. The estimation of survival and litter size of polar bear cubs.  1983. International Conf. Bear Res. and Manage. 5, 260-263

Abstract: The mark/recapture analyses that are currently used to study polar bears (Ursus maritimus) generally underestimate the average number of cubs per litter and assume that the annual survival of cubs is unity.  In this paper, a relationship among the number of yearlings per litter and 2-year-olds per litter is used to derive the survivorship of yearlings, which is then used to solve for the number of cubs per litter.  When this relationship was applied to published population data from North America, the resulting estimated survival rates of yearlings ranged from 0.70 to 0.75, and the estimated average number of cubs per litter was between 1.70 and 1.98.  These findings indicate that current estimates of sustainable yield for polar bear opulations may be in error because the reproductive rate of adult females was likely to be underestimated, and the survival rate of cubs of the year was likely to be overestimated.   

Eagle, Thomas C. and Pelton, Michael R. Seasonal nutrition of black bears in the Great Smoky Mountains National Park.  1983. International Conf. Bear Res. and Manage. 5, 94-101

Abstract: We sampled 86 composites of 646 scats collected at 2-week intervals during 1976 and 1977 and identified 5 seasonal patterns of food use by black bear (Ursus americanus) in the Great Smoky Mountains National Park.  Plant material composed 80% of the diet, and animal remains, mostly insects, were 12%.  Major plant food items were identified.  Crude protein and acid-detergent-fiber content of major food items were determined and nutritional value of each seasonal diet was evaluated.  The early spring diet was of low nutritional value and bears lost weight during spring.  The late spring, summer, and early fall diets were conducive to growth of bears because readily available energy and high-quality proteins were consumed.  The late fall diet, high in available energy, led to rapid increase in weights of bears.

Garshelis, David L., Quigley, Howard B., Villarrubia, Charles R., and Pelton, Michael R. Diel movements of black bears in the southern Appalachians.  1983. International Conf. Bear Res. and Manage. 5, 11-19

Abstract: Hourly movements of radio-collard black bears (Ursus americanus) were monitored periodically from May through December 1976-1979 in the Great Smoky Mountains National Park and Cherokee National Forest in eastern Tennessee.  Diel movements were affected by habitat, food supply, time of year, time of day, sex, age, presence of cubs, and social interactions. Bears were relatively sedentary where food was easily obtained but foraged over larger areas when high-energy foods were dispersed. Nocturnal movements were most affected by food supply.  Daily movements changed seasonally and from year to year in response to seasonal and year-to-year changes in food supply.  Adult males generally traveled more per day than adult females, and young bears traveled further than adult bears.  Females with cubs limited their movements, especially during the spring.  All bears utilized only a small portion of their seasonal range in the course of a day, often traveling in a zig-zag of circular pattern. Circuitous travel routes were particularly evident where bear densities were high.

Graber, David M. and White, Marshall. Black bear food habits in Yosemite National Park.  1983. International Conf. Bear Res. and Manage. 5, 1-10

Abstract: A 5-year study of black bears (Ursus americanus) in Yosemite National Park commenced in 1974 to provide park managers with information necessary for professional stewardship of the species.  At the time, both the public and the National Park Service were concerned about increasing property damage and personal injuries caused by bears, and that actions by visitors and park staff were inimical to a wild, healthy bear population.  Black bear food habits were investigated to determine the role of food of human origin in bear diet.  We found that plants comprised 75% of the diet of Yosemite black bears.  Herbage, including grasses, sedges, and herbaceous dicots, was the principal food during spring and early summer.  Nuts and berries, especially manzanita ( Arctostaphylos spp.) and oak acorns (Quercus  spp.) predominated in the late summer and fall.  Insects, especially ants (Formicidae), and deer (Odocoileus hemionus) were the principal animal foods.  Foods of human origin constituted 15% of the bear diet.  Great annual fluctuations in the proportions of the major food categories reflected varying weather patterns and efforts by the Park Service to eliminate human foods from black bear diets.

Hansson, Rasmus and Thomassen, Jorn. Behavior of polar bears with cubs in the denning area.  1983. International Conf. Bear Res. and Manage. 5, 246-254

Abstract: Observations were made on the behavior of female polar bears (Ursus maritimus) with cubs of the year in the first post-denning period in a densely populated denning area at Kongsoya, Svalbard.  This period has formerly not been studied.  During 2 field seasons 3,148 hours of observations on females, and 6,185 hours on cubs, were obtained from 25 family groups.  Mean litter size was 1.96, mean breakout date 17-18 March.  The bears usually emerged on sunny days.  Mean period spent in the area was 14 days.  Family groups tolerated each other within certain limits, but no evidence for a social hierarchy was found.  Cub motor ability and play intensity increased throughout the period, as did mutual distance within the groups.  Females ate vegetation and bear droppings, but the groups were mainly dependent on the females' fat reserves.  Females were inactive 93.5% of their total time, cubs 91.6%.  The post-denning period is probably of major importance for training and developing the cubs for hard travels on the ice.

Herrero, Stephen. Social behaviour of black bears at a garbage dump in Jasper National Park.  1983. International Conf. Bear Res. and Manage. 5, 54-70

Abstract: A minimum population of 34 black bears (Ursus americanus) visiting and feeding at the town dump in Jasper National Park, Alberta, were observed for over 750 hours on 141 days in 1968.  Females with young of the year visited the dump more than any other group.  Their average litter size of 2.67 for regular dump visitors suggests that food from the dump contributed to reproductive success.  Social interactions between bears were characterized by tolerance, avoidance, and spacing, but we did observe 141 intraspecific agonistic interactions.  In 89 out of 91 agonistic interactions, females with young of the year dominated all other age/sex classes, including adult males.  These females, even when not with their young, used agonistic behaviour to maintain an individual distance of 3 to 30 m.  Twelve postural and 4 vocal components of the agonistic repertoires are described and frequency of use is given for each identified bear.  Agonistic signals were sterotyped but not invariant; physical contact was rare.  Agonistic interactions were more frequent early in the season than later.  The dump was visited by 7,500 to 10,000 tourists; despite hundreds of close approaches, including 57 situations in which people threw rocks or chased bears, a bear never struck, bit, or touched a person.  Bears on 15 such occasions directed agonistic signals toward people; these were similar to signals used in intraspecific encounters.  Subadults and females with their young climbed trees, where they appeared to find safety from harassment.  Bears in trees were seen nursing, playing, sleeping, sheltering, relaxing, or cooling.  The dump offered a food source which was concentrated, high-quality, predictable, and prolonged in time.  Bears exploited this resource by forming social aggregations, tolerating other bears at shorter distances when at the dump than when away. 

Hoak, John H., Clark, Tim W., and Weaver, John L. Of grizzly bears and commercial outfitters in Bridger-Teton National Forest, Wyoming.  1983. International Conf. Bear Res. and Manage. 5, 110-117

Abstract: Information on grizzly bear (Ursus arctos horribilis) distribution seasonal abundance in the Bridger-Teton National Forest, Wyoming, was gathered by direct observation of bears and bear sign and by outfitter interviews in 1977-78.  Operation of commercial outfitting camps was examined and case histories of bear-human interactions documented in 1978 to assess the potential for bear-human conflict.  We compiled 394 reports of grizzly bear for 1968-78, including 228 reports for 1977-78.  Report localities were distributed widely throughout the northern portion of the Forest, but concentrated in Teton Wilderness (Buffalo Ranger District).  An estimated 45 grizzlies occurred on the Forest during May-November 1977: 15 single bears and 10 females with 20 young.  In 1978, 37-38 grizzly bears were tallied during May-November: 21-22 single bears and 7 females with 9 young.  Each of 20 outfitter camps examined had conspicuous bear attractants, including low-hanging racks of game meat, open garbage pits, and unsealed livestock and human foods. Attractants were near human quarters and concealment cover for bears.  Eighteen camps had histories of bear encounters.  Management guidelines could reduce attraction of camps for bears.

Jorgenson, Carole J. Bear-sheep interactions, Targhee National Forest.  1983. International Conf. Bear Res. and Manage. 5, 191-200

Abstract: Black bear (Ursus americanus), grizzly bear (U. arctos), and domestic sheep interactions and competition were investigated using radiotelemetry on the Targhee National Forest in Idaho and Wyoming during 1976 and 1977. (Black and grizzly bear intra- and interspecific relationships are discussed in terms of habitat utilization.)  Radio-monitored movements of 7 black bears and 1 grizzly were compared with movements of sheep herds on selected forest sheep allotments to investigate bear behavior near sheep herds and determine the extent of interspecific conflicts.  Competition between bears and sheep occurred when they utilized the same plants (primarily grasses and forbs) that were limited by either abundance or seasonal availability.  Additional conflict, resulting in losses of sheep to bear predation, occurred during concurrent habitat use by bears and sheep.    

Keay, Jeffrey A. and Van Wagtendonk, Jan W. Effect of Yosemite backcountry use levels on incidents with black bears.  1983. International Conf. Bear Res. and Manage. 5, 307-311

Abstract: Black bear (Ursus americanus) incidents, defined as property damage or personal injury by bears, increased dramatically in recent years in the backcountry of Yosemite National Park, California.  Since all backcountry zones do not receive the same level of visitor use, incidents could be compared between zones of various use levels.  Data collected from 1976 through 1979 showed that as visitor density increased, reported bear incidents increased linearly.  In order to reduce or maintain bear incidents at acceptable levels, managers of backcountry areas may have to reduce nonaversive bear/human encounters and the availability of human food items. 

Kendall, Katherine C. Use of pine nuts by grizzly and black bears in Yellowstone National Park.  1983. International Conf. Bear Res. and Manage. 5, 166-173

Abstract: Whitebark pine (Pinus albicaulis), an important tree of high altitudes in the northern Rocky Mountains and Sierra Nevada, produces nuts eaten by bears.  Grizzly bear (Ursus arctos) and black bear (U. americanus) use of pine nuts was studied in Yellowstone National Park and adjacent areas during 1978 and 1979.  Spring use appeared to be correlated with cone production in the preceding year, while fall use was correlated with the current crop.  Most of the nuts eaten by bears came from cones cached by red squirrels (Tamiasciurus hudsonicus).  Pine nuts were a nutritious food which was often present in early spring and late fall when alternate foods were scarce or low in digestible energy and when nutritional requirements of bears were high.  No evidence was found that bears ate the nuts of limber pine (P. flexilis).

Kingsley, M. C. S., Nagy, J. A., and Russell, R. H. Patterns of weight gain and loss for grizzly bears in Northern Canada.  1983. International Conf. Bear Res. and Manage. 5, 174-178

Abstract: Seasonal weight change in the grizzly bear (Ursus arctos) in two populations in northern Canada was studied by fitting growth curves to spring and fall weights.  The spring weight of females levels off soon after the average age of first reproduction; that of males continues to increase through maturity and eventually reaches nearly twice that of females.  Males lost in winter 22% of their fall weight, the fraction changing very little with age.  The weight change in females is much larger, and continues to increase with age, the oldest females gaining in summer 70% of their spring weight and losing in winter 40% of their fall weight.  Mature females gain and lose not only relatively, but absolutely, more weight than males.

Knight, Richard R. and Judd, Steven L. Grizzly bears that kill livestock.  1983. International Conf. Bear Res. and Manage. 5, 186-190

Abstract: Thirty-seven grizzly bears (Ursus arctos) equipped with radio transmitters were monitored in and around Yellowstone National Park between 1974 and 1979.  Ten of the bears were known or suspected to kill livestock; 3 preyed on cattle, 6 on sheep, and 1 on both.  Bears that killed livestock ranged widely in and out of Yellowstone Park and normally exhibited foraging habits similar to those of other bears.  All subadult and adult bears known to have the opportunity killed sheep.  Most bears that come into contact with cattle did not make kills.  All known cattle killers were adult bears, while 4 sheep killers were subadults.  Sheep grazing should be reduced as much as possible on grizzly range, and cattle grazing allowed only if owners are willing to absorb predation losses.

Kolenosky, George B. and Prevett, J. Paul. Productivity and maternity denning of polar bears in Ontario.  1983. International Conf. Bear Res. and Manage. 5, 238-245

Abstract: Aerial surveys to assess polar bear (Ursus maritimus) productivity were conducted along the northern coast of Ontario during February and March, 1974 through 1978.  Cub production varied from 33 to 112 annually, and averaged 71 during the 5 year period.  Average litter size was 2.0. Emergence extended from late February to early April with the peak around 1-15 March.  Maternity dens occurred throughout the northern coast; distances inland extended from 29 to 118 km.  The section between the Winisk and Severn Rivers consistently contained the greatest concentration of family groups.  Most dens were situated in open or treed bog habitat where snow accumulation was greatest.  Maternity dens lacked the presence of an earth chamber or intricate internal structures recorded in areas futher north.  After emergence, family groups remained in the den vicinity for 2 to 3 weeks.  Movement to the sea was usually quite direct, and invariably towards Hudson Bay, although James Bay was sometimes much closer.  Some groups traveled over 300 km to reach seal (Phoca hispida) hunting areas on the Hudson Bay ice.  Maternity denning on Akimiski Island represents the most southerly occurrence of reproducing polar bears currently known anywhere in the world.  

Larsen, Thor, Jonkel, Charles, and Vibe, Christian. Satellite radio-tracking of polar bears between Svalbard and Greenland.  1983. International Conf. Bear Res. and Manage. 5, 230-237

Abstract: An aerial survey program in 1977 and 1979 revealed that tracks of polar bears (Ursus maritimus) were abundant from Svalbard to Northeast Greenland south of 81° north latitude.  In order to obtain evidence on possible exchange of polar bears between Svalbard and Greenland, 4 bears were instrumented with satellite radio collars from the ice drift station FRAM l in the northern Greenland Sea.  After 1 month, 2 bears had moved eastwards to Svalbard and Frans Josef Land, and 2, which were instrumented further south, had moved southwards with the East Greenland Current.  At times, some of the instrumented bears must have moved more than 40 km per day.  Polar bears are able to compensate for the ice drift current, and can move against it.  Helicopter observations revealed that there is an influx of bears, and particularly females with cubs, from the pack ice area off Northeast Greenland to Svalbard and the Barents Sea in early spring.

LeCount, Albert L. Denning ecology of black bears in central Arizona.  1983. International Conf. Bear Res. and Manage. 5, 71-78

Abstract: A total of 68 black bear (Ursus americanus) dens were located by radio-tracking 27 radio-instrumented animals from October 1974 through May 1979.  Regardless of mild weather conditions and year-around availability of food, all bears denned.  Duration of denning varied with sex and age class but averaged 4 to 5 months.  Ninety-one percent of the dens studied were located in the Interior Chaparral vegetation type.  Site selection appeared to be based on a combination of dense vegetative cover at bear height (0.3-1.8 m) and early development of spring forage.  All dens were located under large rocks.  Den sites appeared to be abundant, with most bears preparing numerous dens.  Only 6% of our bears reused dens.  Den sites of adult animals appeared to be within normal home range areas.  Because of the ready availability of den sites, plans for conversion of chaparral areas to grassland should limit neither bear den sites nor bear populations.

Lindzey, James S., Alt, Gary L., McLaughlin, Craig R., and Kordek, Walter S. Population response of Pennsylvania black bears to hunting.  1983. International Conf. Bear Res. and Manage. 5, 34-39

Abstract: Annual legal harvests of black bears (Ursus americanus) in Pennsylvania during 61 hunting seasons from 1915 through 1979 ranged from 149 to 929 and averaged 424.  Data for 1971-1977 showed high hunting pressure, with 95,000-250,000 hunters estimated active during 1-day bear seasons and success averaging 318-507 hunters per bear harvested.  In 1971-1979 total known bear losses were 92-129 for years with no hunting and 297-1017 for years with bear seasons.  In hunting years, legal kills accounted for 70-84% of all losses; other significant causes of loss were illegal kills (including cubs), road kills, and damage control.  Increasing hunting pressure in 1976 and 1977 and a decline in the average age of harvested bears from 4.2 in 1967 to 2.8 in 1976 led to closed seasons in 1977 and 1978.  In 1979, a 1-day season resulted in 736 legal kills and 120 cub kills; known losses totaled 1017.  A high reproductive rate and good cub survival, probably related to good nutrition, have allowed the Pennsylvania black bear population to respond with sustained high productivity that has compensated for population losses in most years.  Control of hunting pressure is the most important management need.

Manville, Albert M. Human impact on the black bear in Michigan's Lower Peninsula.  1983. International Conf. Bear Res. and Manage.  5, 20-33

Abstract: Thirty-five black bears (Ursus americanus) were captured (22 males, 13 females), 25 were radio-collared, 4,224 telemetric observations, and 1,112 radio triangulations were made from ground and air between September 1977 and March 1980 in connection with a study of the interactions between humans and bears in Michigan's Lower Peninsula (mainly in Crawford, Kalkaska, Missaukee, and Roscommon counties). Identified positive effects of humans on bears included changes in hunting regulations possibly resulting in an increasing bear population; bears frequently using oil pipeline right-of-ways, oil well service lanes, and lumber roads as travel routes; early-successional vegetational stages induced by roadside cutting, commercial lumbering, clear-cutting deer (Odocoileus virginianus) management projects, and controlled burns; and bee-keeping.  Negative effects included loss of habitat due to human encroachment, heavy automobile traffic, hunting aided by service roads, marked bears (11 of 28) and females with cubs being shot, and bears which fled their dens when approached.  Questionable impacts included proximity of den sites to centers of human activity, closure of most sanitary landfills, and disturbance by small game and deer gun hunters.  Unknown impacts included those of oil wells, snowmobile activity near denned bears, and contact between humans and bears.  Data were insufficient to indicate whether a high incidence of periodontal disease (11 of 35 bears in varying degrees of severity) affected bear behavior, although diseased animals suffered tooth loss and jaw and gum atrophy.  Twenty-three marked animals were sighted and reported 63 different times by the public.  Forty-six nuisance and damage complaints were reported in the study area between August 1977 and July 1980.  Average home range for males (>= 6 months telemetric data) was 150.4 km² (SD = 96.6 km²); for females, 68.9 km² (SD = 64.0 km²).  Six adults made seasonal summer treks of 140, 105, 50, 47, 42, and 32 km from fall-winter-spring home ranges, returning before denning. 

Martin, P. Factors influencing globe huckleberry fruit production in Northwestern Montana.  1983. International Conf. Bear Res. and Manage. 5, 159-165

Abstract: Globe huckleberry (Vaccinium globulare) fruit is a major food source for the grizzly bear (Ursus arctos horribilis) in northwestern Montana. A ranked-set sampling pattern was used to determine the effects of wildfires, timber harvest practices, and physical and vegetative site characteristics on globe huckleberry fruit production.  Timber stands not disturbed within the last 60 years were among the least-productive sites sampled.  Stands on mesic, northern or eastern aspects that were burned by wildfire 25-60 years ago, or clearcut and broadcast-burned 8-15 years ago, were the most productive sites.  Wildfires or timber harvests on xeric, southern or western aspects reduced fruit production and percent cover of globe huckleberry plants, as did scarification of clearcuts on any aspect.  The relationships between fruit production and vegetative site characteristics reflected the age and physical features of the stands, though fruit production was not related to the percent cover or height of the globe huckleberry plants.  Crop failures were apparently related to meteorological events.  Therefore, long-range planning to assure production of globe huckleberry fruit crops in the future is recommended for manipulation of grizzly bear habitat.

Martin, Sandra K. and Jonkel, Charles J. Use of sea ice habitat by polar bears.  1983. International Conf. Bear Res. and Manage. 5, 255-259

Abstract: Use of the habitat by polar bears (Ursus maritimus) on coastal sea ice was investigated through observation of undisturbed polar bears and their environment.  Nearshore sea ice was kept under 24-hour surveillance from 4 field camps established successively from 19 May to 19 July 1979 on island coasts bordering Barrow Strait, Northwest Territories, Canada.  Two of these study areas received relatively more use by polar bears than the other 2.  Polar bears also exhibited selection of sea ice types within each study area.  Recorded activities of the bears included travel, play, sleep, and several hunting behaviors. 

McArthur Jope, Katherine L. Habituation of grizzly bears to people:  a hypothesis.  1983. International Conf. Bear Res. and Manage. 5, 322-327

Abstract: Reports of grizzly bear (Ursus arctos) observations between 1977 and 1979 in Glacier National Park were examined to test whether the behavior of grizzly bears was different in areas with high versus low levels of human activity.  In both types of areas, females with young were more likely than adults and subadults to avoid human-use areas and showed little habituation to people.  A midseason increase in habituated behavior by adult and subadult bears occurred in both areas, but adults and subadults showed a greater degree of habituation throughout the season in the high-use area.

Meagher, Mary and Phillips, Jerry R. Restoration of natural populations of grizzly and black bears in Yellowstone National Park.  1983. International Conf. Bear Res. and Manage. 5, 152-158

Abstract: Yellowstone National Park began an intensive bear management program in 1970, with the stated goal of restoring and maintaining natural populations of grizzly bears (Ursus arctos) and black bear (U. americanus).  The Park closed the last of its large open-pit garbage dumps in 1971.  During the decade 1970-79, bear management went through 3 phases.  In 1970-72 most incorrigible bears that had developed strong ties to sources of human foods were translocated or removed.  This period also included intensive efforts to educate people, increased law enforcement, intensified sanitation, refinement of management techniques, and development of a monitoring system to provide management information.  The next period, 1973-78, represented a transition from emphasis on correction of a situation to awareness that a high level of preventive bear management must be routine and never-ending part of Park operations. By the summer of 1979, the bears with prior knowledge of sources of unnatural foods within the Park appeared to be gone.  Thus, in 10 years Park management appears to have attained the objective of restoring the populations of bears to subsistence on natural forage to the extent that outside influences beyond the Park's control will permit.  The future of the grizzly bear in and around Yellowstone appears increasingly dependent on management decisions which give the bear adequate priority over human desires.

Miller, Gary D. Responses of captive grizzly and polar bears to potential repellents.  1983. International Conf. Bear Res. and Manage. 5, 275-279

Abstract: Potential bear repellents were tested on 2 male grizzly bears (Ursus arctos horribilis) and 2 female polar bears (U. maritimus) at the Churchill Bear Laboratory, Churchill, Manitoba.  Fifteen to 18 stimuli were tested on each bear.  The stimuli were selected randomly from a list of possible repellents that included recorded bear and people sounds, bells, horns, chemicals, and others.  Extremely loud, sharp sounds and most of the chemicals were consistently repellent.  Although some of the stimuli were very effective, the effects on the bears were consistently short-lived.  Laboratory tests on caged animals is a valid method for screening the effectiveness of a large number of stimuli in a short time, but the results of such tests must be verified by field tests. 

Mysterud, Ivar. Characteristics of summer beds of European brown bears in Norway.  1983. International Conf. Bear Res. and Manage. 5, 208-222

Abstract: One hundred and nineteen European brown bear (Ursus arctos arctos) daybeds and their surroundings were studied in Hedmark County, Norway, in 1974-77.  In addition to bed type and size, the following parameters were measured or estimated: slope, aspect, altitude, type and age of vegetation, cover, distance to close objects, and distance from the site to farms and roads.  Abiotic exposure avoidance, concealment, defense/safety, and construction behavior are discussed as elements of bed site selection.  Bed studies based on field signs met with difficulties such as distinguishing daybeds from dens, and problems of bed classification are discussed.

Nelson, Ralph A., Folk, G. Edgar Jr., Pfeiffer, Egbert W., Craighead, John J., Jonkel, Charles J., and Steiger, Dianne L. Behavior, biochemistry, and hibernation in black, grizzly, and polar bears.  1983. International Conf. Bear Res. and Manage. 5, 284-290

Abstract: Annual behavioral and biochemical patterns of black bears (Ursus americanus), grizzly bears (Ursus arctos horribilis), and polar bears (Ursus maritimus) were reviewed.  We propose that black and grizzly bears show 4 annual physiological stages: Stage I--hibernation, in which lean body mass is preserved and body fat supplies energy; Stage II--walking hibernation, in which the biochemistry of hibernation is integrated with physical activity, but food and water intake are minimal; Stage III--normal activity, in which patterns are consistent with those of nonhibernating mammals; and Stage IV--hyperphagia, which increases fat reserves for hibernation.  For polar bears, using published reports and recently collected data, we propose that all 4 stages are possible and that polar bears appear able to shift between Stages l and ll in both summer and winter, which permits successful adaptation to the arctic environment. 

Nozaki, Eikichi, Azuma, Shigeru, Aoi, Toshiki, Torii, Harumi, Ito, Tetsuro, and Maeda, Kishio. Food habits of Japanese black bear.  1983. International Conf. Bear Res. and Manage. 5, 106-109

Abstract: The food habits of Japanese black bears (Selenarctos thibetanus japonicus) were studied in the Neo Nishitani Valley, Gifu Prefecture, between 1973 and 1977.  The bears live in the temperate forest zone where beech (Fagus crenata), Mongolian oak (Quercus mongolica var. grosserata), and Japanese white oak (Q. serrata) dominate.  Their diet was composed mostly of plant matter throughout the year.  During spring, bears ate nuts of beech and oaks which had fallen in the previous year, beech buds and shoots of herbaceous plants.  During summer, bears ate a large quantity of animal matter such as ants and other insects, and much plant matter such as the fruits of Japanese cluster cherry (Prunus grayana) and dogwood (Cornus controversa).  Nuts of oaks and beech were consumed in large quantities during fall.  A census of the numbers of fruit trees with branches broken by bears revealed that the animals mainly used beech in 1973, Japanese white oak and Japanese chestnut (Castanea crenata) in 1974, chestnut and Mongolian oak in 1975, beech in 1976, and chestnut in 1977.  In 1976, when few broken branches of beech tree were found, fallen beechnuts were eaten. 

O'Pezio, John, Clarke, Stephen H., and Hackford, Charles. Chronology of black bear denning in the Catskill Region of New York.  1983. International Conf. Bear Res. and Manage. 5, 87-93

Abstract: In radio-telemetry studies of black bears (Ursus americanus) in the Catskill region of New York State during 1975-79, denning chronology was recorded for 62 den entries and 38 exits by 35 male and female bears 1 to 17 years of age.  The median den entry date for female bears with cubs (22 November) was somewhat earlier than that for pregnant females (24 November) and barren females (30 November).  Collectively, females denned significantly earlier than males (24 November versus 10 December).  Median den emergence dates also varied with sex and reproductive status.  Males were the first to leave their dens (26 March), followed by females with yearlings (5 April) and barren females (8 April).  Females with cubs left their den site significantly later (15 April) than males and females with yearlings.  Although autumn temperatures, snowfall, and snow depths differed significantly between years, they appeared unrelated to denning dates.

Palumbo, P. J., Wellik, Dianne L., Bagley, Nancy A., and Nelson, Ralph A. Insulin and glucagon responses in the hibernating black bear.  1983. International Conf. Bear Res. and Manage. 5, 291-296

Abstract: To study the hormonal changes during hibernation in the black bear (Ursus americanus), 2 adult male bears were injected with insulin and with glucagon during their active and hibernating phases, and plasma urea, glucose, insulin, glucagon, and corticosteroids were measured before and after.  The baseline urea values decreased during hibernation a pattern consistent with protein conservation.  Baseline insulin values increased during the fall active phase, when bears are hyperphagic, returning to the normal range during early hibernation.  Baseline glucagon levels increased during the fall hyperphagia phase and early hibernation and then tended to decrease at the end of hibernation. Baseline corticosteroid levels were lower during the summer active phase than during the other three periods.  The insulin, glucagon, and corticosteroid responses to glucagon and insulin injection were variable, but in general were delayed during early hibernation.  The plasma glucose response to insulin stimulation was also delayed during early and late hibernation but more so during early hibernation.  The glucose response to glucagon stimulation was delayed to similar degrees during both early and late hibernation.  These findings are consistent with decreased glucose utilization and increased lipolysis during hibernation.  Furthermore, the apparent increase in glucose utilization at the end of hibernation when fat stores are nearly exhausted suggests a continuum of metabolic activity from early to late hibernation with a transition to the active phase by the end of hibernation.

Roth, Hans U. Diel activity of a remnant population of European brown bears.  1983. International Conf. Bear Res. and Manage. 5, 223-229

Abstract: The temporal distribution of activity and rest over the 24-hour cycle is characteristic of a species and, to some extent, a function of the environment.  Parameters of this distribution could possibly be used to estimate the stress on a given animal population.  To measure the diel activity pattern of the last brown bears (Ursus arctos) of the Alps, which live in a relatively densely populated area (70 human inhabitants/km²) in northern Italy, 3 bears were equipped with radio collars.  The bears were active about 50% of their time.  Pooled hourly data for the proportion of telemetry readings showing bear activity were combined, through an iterative procedure based on a succession of chi-square values, into 5 diel periods showing significant (P<0.01) differences.  The basic pattern of diel activity was found to be bimodal with the major activity peak in the evening from 1800 to 2300 hours and a secondary peak in the early morning between 0500 and 0800.  The main rest period was in the late morning from 0800 to 1300.  However, the variability of the activity schedule, even of the same individual from day to day, was large; bears could be found active at any time of the day.

Schwartz, Charles C. and Franzmann, Albert W. Effects of tree crushing on black bear predation on moose calves.  1983. International Conf. Bear Res. and Manage. 5, 40-44

Abstract: Mortality of young moose calves (Alces alces gigas) was evaluated on the Kenai Peninsula, Alaska, during spring and early summer 1977 and 1978.  Studies were conducted both inside and outside of a 461-ha browse-rehabilitated area (Willow Lake) where standing vegetation had been crushed with LeTourneau tree crushers in winter 1974-75.  Uncrushed areas (control) were regrowth of vegetation that was burned by forest fire in 1947.  Moose calves were radio-collared with mortality-sensor transmitters soon after birth.  Black bear (Ursus americanus) predation accounted for 40-42% of the calf mortality in control areas (6 of 15 calves collared in 1977 and 10 of 24 in 1978); no calves (of 8 collared in 1978) were killed by black bears within the rehabilitated areas. Movements of 23 radio-collared black bears were also monitored during 1978 and 1979.  Radio-collard bears, including 15 whose home ranges bordered or included rehabilitated areas, either did not utilize or avoided crushed sections.  Results of our studies indicated that neonatal mortality of moose calves was significantly reduced within browse-rehabilitated areas.

Servheen, Christopher and Klaver, Robert. Grizzly bear dens and denning activity in the Mission and Rattlesnake Mountains, Montana.  1983. International Conf. Bear Res. and Manage. 5, 201-207

Abstract: Forty-one grizzly bear (Ursus arctos horribilis) dens were found in the Mission and Rattlesnake Mountains, Montana, from 1976 through 1979.  Ten of these dens were used by transmitter-equipped grizzly bears.  Thirty-nine dens were excavated in open, side-hill park habitat and 2 were under forest canopy.  Two dens occurred at 1250 m while 39 were between 2050 and 2500 m. Slope angle of sites averaged 30° for 15 measured dens.  Dens occurred on all aspects except northwest.  Movement to the den site in the fall was independent of low-elevation weather conditions and occurred between 10 October and 20 November.  Two adult females moved to their dens prior to any snow and may have displayed a period of pre-hibernation lethargy prior to final den entry. Final den entry was closely associated with severe snowstorms at the den site that apparently sealed the den entrance with snow.  Final den entry dates varied from 2 November until after 21 November.  Dates of emergence varied from prior to 31 March to 26 April.  Adult females accompanied by young remained at the den site after emergence for 7 to 12 days.  All other grizzly bears left the den and moved to lower elevations immediately after emergence.  One transmitter-equipped grizzly bear used its winter den during August as a bedding site.  This is the first verification of summer use of a den by a grizzly bear.  Two adult male black bears (Ursus americanus) were radio-instrumented to determine their denning habits.  Both denned below 1800 m under forest canopy.  Significant differences (P<0.001) between den entrance height of excavated black bear and grizzly bear dens indicate that this measurement may be a useful indicator of species.

Shaffer, Mark L. Determining minimum viable population sizes for the grizzly bear.  1983. International Conf. Bear Res. and Manage. 5, 133-139

Abstract: A stochastic computer simulation is presented for use in determining the relationship of population size to extinction probabilities for populations of grizzly bears (Ursus arctos).  Published data on numbers, age, sex reproduction, and mortality for the grizzly bear population of Yellowstone National Park were used to develop and test several simulation models.  The results indicate that, for the Yellowstone grizzlies, 35 to 70 bears constitute a minimum viable population (the smallest population with a 95% probability of surviving at least 100 years).  Minimum area requirements for populations of this size range from 700 to 10,000 km².

Smith, Jane Kapler. BIMS--the bear reporting network for the National Park Service.  1983. International Conf. Bear Res. and Manage. 5, 297-301

Abstract: The U.S. National Park Service employs a nationwide computer network to make reports of bear-related events available to managers in parks, regional, and national offices simultaneously.  This is the Bear Information Management System, BIMS.  It is operated by managers and technicians through use of interactive programs.  A flexible structure enables each park to store data in up to 91 information categories, using a reporting form tailored for field use.  Through database management programs, managers retrieve specific records or analyze large volumes of data to carry out effective day-to-day management and to plan for future needs.  System support at the national level and commitment by the user parks to complete, accurate data reporting are essential for reliable operation.

Stringham, Stephen F. Roles of adult males in grizzly bear population biology.  1983. International Conf. Bear Res. and Manage. 5, 140-151

Abstract: Developing on my earlier work (Stringham 1980) and that of McCullough (1981), influences of adult male abundance on rates of reproduction and subsequent attrition (mortality + net emigration) were evaluated for grizzly bears (Ursus arctos) by analysis of the data of Craighead et al. from Yellowstone National Park 1959-70.  Years when adult males were most abundant were also those in which (1) the litters conceived were smallest when censused at median age 0.5 year postpartum, and (2) the cohorts born were comprised of fewest litters at that age.  Cohorts produced during years of peak adult male abundance were not only smallest at age 0.5, but showed the highest rates of attrition to at least age 2.5 years.  Apparently adult male abundance and/or some closely linked factor, perhaps availability of food, governed not only abundance but quality of infants, which in turn governed survivorship and competitive ability for space and resources in Yellowstone National Park to age 2.5.  That coincides generally with relationships between rates of reproduction and of attrition vs. abundances of adult males and of food observed by Rogers (1976, 1977) for black bear in Minnesota.  McCullough (1981) reached some of these same conclusions.  

Tate, Jane and Pelton, Michael R. Human-bear interactions in Great Smoky Mountains National Park.  1983. International Conf. Bear Res. and Manage. 5, 312-321

Abstract: An ethological investigation of panhandler black bear (Ursus americanus), conducted in Great Smoky Mountains National Park from 1976 through 1978, focused on agonistic behavior exhibited by these bears in their interactions with park visitors.  Seven different types of aggression were recorded.  Apparent precipitation factors for such behavior were divided into 20 categories, e.g., handfeeding, petting, photographing, crowding.  Of 392 panhandling sessions, 43.9% involved at least one incidence of agonistic behavior; overall, 624 aggressive acts were recorded.  Some types of aggression were more likely to occur, and certain precipitating factors were likely to result in specific types of agonistic behavior.  Less than 6% of all aggression led to actual physical contact with visitors.  Some individual bears reacted more aggressively than others in their interactions with people.  In general, more aggressive behavior was shown by males.  Management implications include the need for visitor education, enforcement of National Park Service regulations, removal of garbage, and priorities in relocation of bears.

Williamson, James F. Jr. and Whelan, James B. Computer-assisted habitat mapping for black bear management in Shenandoah National Park.  1983. International Conf. Bear Res. and Manage. 5, 302-306

Abstract: The objective of black bear (Ursus americanus) management in Shenandoah National Park has been to minimize property damage and personal injury to Park visitors while maintaining the bear population as a part of the natural fauna.  Past management attention has been directed at educating visitors; however, future efforts will incorporate more biologically oriented strategies, and will require new information on ecological matters such as bear habitat suitability, the location of areas of sensitive or critical habitat, and the impacts of proposed developments on bear habitat.  A computer mapping system designed to assist in the bear management effort by meeting these types of information needs is described.  Sample maps were prepared.

Wooldridge, Donald R. Polar bear electronic deterrent and detection systems.  1983. International Conf. Bear Res. and Manage. 5, 264-269

Abstract: The responses of free-ranging polar bears (Ursus maritimus) to acoustic and electrified-fence repellents, and to trip-wire and proximity detection systems, were evaluated in a 4-year study.  Natural and synthesized acoustic repellents deterred 69% (N=71) of bears who attempted to enter a test perimeter.  Position of speakers, sound amplitude, and the timing of presentations are important factors in the effectiveness of acoustic repellents.  A 20-kV electrified fence repelled 35% (N=52), and a 60-kV fence repelled 33% (N=6) of intruding bears.  Tests on a patch of polar bear fur indicated that a nominal 200 kV is required to reliably deliver an electric shock through the highly insulating hair of this species.  Tests on single, double, and triple trip-wire fences yielded a 93% (N=161) success rate for detecting intruding bears.  A proximity (capacitance-sensing) detection system detected 100% (N=13) of bear entries, but was too sensitive to stray electrical inputs.  A modified system in the 2nd season detected 63% (N=41) of intrusions.  Refined versions of these devices could offer significant improvement in safety for personnel who must work in close proximity to free-ranging polar bears, black bears (U. americanus), or grizzly bears (U. arctos).

Worley, David E., Greer, Kenneth R., and Palmisciano, Dan. Possible relationships between trichinellosis and abnormal behavior in bears.  1983. International Conf. Bear Res. and Manage. 5, 280-283

Abstract: Data compiled from parasite studies of grizzly bears (Ursus arctos) and black bears (U. americanus) in the Yellowstone and Glacier National Park populations and surrounding areas of Montana and Wyoming during 1969-79 are reviewed with reference to the possible influence of infection with the muscleworm Trichinella sp. on bear behavior.  In grizzly bears, the high prevalence of this parasite (61% of 254 bears infected), the elevated larval concentrations in sensitive anatomical sites such as the tongue (average, 51 larvae per gram of tissue), and the chronic nature of bear infections as indicated by the tendency for highest infection rates to occur in older age classes (_16 yrs.), suggest a potential behavior-modifying effect might exist.  However, retrospective analysis of recent human attacks by 4 grizzlies and 2 black bears in the northern Rocky Mountain region failed to demonstrate a consistent connection between erratic conduct and levels of Trichinella larvae (trichinae) in bear tissues.  Clinical similarities of trichinellosis in bears and humans are hypothesized, and possible behavioral effects of ursine trichinellosis are discussed.

Zager, Peter, Jonkel, Charles, and Habeck, James. Logging and wildfire influence on grizzly bear habitat in Northwestern Montana.  1983. International Conf. Bear Res. and Manage. 5, 124-132

Abstract: Vegetation was sampled on 330 sites known to be used by grizzly bears (Ursus arctos).  The response to disturbance of 6 shrub species important as grizzly bear foods was determined by comparing their percent canopy cover on disturbed sites with that on undisturbed, old-growth sites.   Overall, the canopy cover of these species was higher on sites burned by wildfire 35-70 years ago than on comparable old-growth sites.  The canopy cover of these species was generally less on clearcut sites where the slash was bulldozer-piled than on burned sites.  The shrub response on clearcut sites where slash was not treated was intermediate; some shrubs increased while others declined.  Site treatment is at least partially responsible for this differential response; bulldozer-scarification apparently destroys the vegetative reproductive organs of these shrubs.  Habitat use patterns of 4 radio-collared grizzly bears were studied in 1979.  Grizzly bears preferred snowchutes, ridgetops, and creek bottoms during the spring; they preferred shrubfields, slabrock, ridgetops, and creek bottoms during the summer/fall.  Cutting units and habitat affected by open, travelled roads were avoided throughout the active season.  Cutting units used by grizzly bears were generally isolated from human disturbance factors and provided nearby cover (within 50 m) in the form of well developed shrub strata, leave trees, and cutting unit boundaries.