Michael R. Pelton

Activity of Black Bears in the Great Smoky Mountains National Park

The activity of black bears ( Ursus americanus ) in the Great Smoky Mountains National Park was studied through the use of motion sensitive radio-collars. Bears exhibited a tendency toward a crepuscular activity rhythm, although mating activity and changes in the nature and abundance of the food supply modified this pattern seasonally. The most distinct crepuscular rhythm was observed in the spring when expendable energy was limited by a paucity of nutritious food. Bears were more active and more diurnal during the summer when berries were abundant. The level of activity reached a peak during the June–July breeding season. Extensive nocturnal activity was observed only during the fall, and probably was associated with increased foraging in preparation for denning. Activities of females with cubs did not vary seasonally, and this group was active more than any other sex-age group; subadults were active more than solitary adults of their respective sex. Rain, snow, and temperatures above 25°C or below 0°C substantially reduced the level of activity.

Genetic relatedness and female spatial organization in a solitary carnivore, the raccoon, Procyon lotor

Among mammals, some of the most common types of cohesive social groupings originate from natal philopatry through the extended mother family. This retention of females within social groups (i.e. the nonrandom dispersion of female relatives in space) should affect population genetic structure. We examined the relationship between genetic relatedness and female spatial organization in a wild population of the North‐American raccoon, Procyon lotor, a solitary carnivore in east Tennessee. Multilocus genetic band‐sharing data and 3½ years of radiotelemetry observations were used to study the spatial and genetic relationships among 38 adult females. DNA amplification employing primers of arbitrary sequence (random amplified polymorphic DNA; RAPD) indicated that female philopatry in raccoons led to a greater likelihood of neighbours being more related than expected by chance. Genetic distance based on RAPD band frequency was positively correlated with spatial distance among females (P = 0.0001) and genetic similarity was positively correlated with the extent of home‐range overlap (P = 0.0028). Philopatry seemed biased towards females; average female–female similarities were greater than average male–male similarities (P = 0.0001), or average male–female similarities (P = 0.0001). High home‐range overlap among some females with low or moderate levels of band sharing indicated that maternal inheritance of space was not a prerequisite for establishing or sharing home ranges. Female philopatry was the most probable explanation for the nonrandom spatial and genetic association of raccoons in east Tennessee.

Seasonal Foods and Feeding Ecology of Black Bears in the Smoky Mountains

Between June 1969 and January 1972, 75 stomachs and 1,025 scats from black bears (Ursus americanus) were collected from the Great Smoky Mountains National Park and vicinity for food content analysis. Grasses and the other herbaceous leaves and stems, squawroot (Conopholis americana), huckleberries (Gaylussacia spp.), black cherry (Prunus serotina), acorns from oaks (Quercus spp.), blackberries (Rubus spp.), and blueberries (Vaccinium spp.) composed 81 percent of the diet by volume. Eleven percent of the food consumed was animal matter, principally Coleoptera and Hymenoptera. Artificial food constituted 6 percent of the diet. The most critical season with regard to food availability appears to be late fall because mast (nuts) is the only preferred natural food source available and mast failures occur frequently. There is additional evidence that nutrition, productivity, movement, and bear/person incidents are also influenced by feeding ecology of the

Environmental Relationships and the Denning Period of Black Bears in Tennessee

The denning period of black bears ( Ursus americanus ) in the Great Smoky Mountains National Park was determined through the use of motion-sensitive transmitter collars. Most (14, 83%) instrumented bears entered dens between 25 December and 7 January. Adult females entered dens first ( X = 31 December), subadults of both sexes entered dens next ( X = 7 January), and adult males entered dens last ( X = 12 January). Emergence generally occurred between 25 March and 7 April, with the denning period averaging 90 days. Females with cubs vacated dens later ( P < 0.002) and denned longer ( P < 0.011) than other adult females. Den entry and strong fidelity to dens by all instrumented bears indicated that the intensity of dormancy did not differ from that in northern regions; however, duration of dormancy was considerably shorter. Cumulative effects of increased precipitation and lower maximum and higher minimum temperatures, which correspond to passage of a low pressure weather front, provided a proximate stimulus to enter dens. Food supply also appeared to affect denning in a proximal manner because bears denned earlier in years with fair to poor mast yields than in years with excellent mast yields ( P < 0.0004). Emergence dates were less strongly correlated with environmental factors. Ultimate synchronization of denning behavior with the environment is best explained by a circannual (endogenous) rhythm; this rhythm is easily shortened or lengthened allowing flexibility depending on environmental variation and the ecology of a species. Such a rhythm encompasses the observed variation in environmental factors affecting the denning period of bears over their broad geographic range and diverse ecological conditions.

Ecology of Florida Black Bears in the Okefenokee‐Osceola Ecosystem

Abstract: The population status of the Florida black bear (Ursus americanus floridanus) is problematic within many portions of its range and its potential listing as a federally threatened species has been the subject of legal debate. We studied Florida black bears in 2 areas in the Okefenokee-Osceola ecosystem in southeast Georgia (i.e., Okefenokee) and north Florida (i.e., Osceola) from 1995 to 1999 to evaluate relationships between population characteristics, habitat conditions, and human activities. Bears in Okefenokee were hunted and those in Osceola were not. We captured 205 different black bears (124M:81F) 345 times from June 1995 to September 1998. We obtained 13,573 radiolocations from 87 (16M:71F) individual bears during the study. In Okefenokee, black gum (Nyssa sylvatica) and saw palmetto (Serenoa repens) fruits were the most important foods for bears based on scat analysis. In Osceola, corn from white-tailed deer (Odocoileus virginianus) feeders was the most stable food source but saw palmetto was heavily used when available. Corn from deer feeders was not available in Okefenokee. Adult bears in Osceola were 29% heavier than those in Okefenokee (t82 = 3.55, P < 0.001). The mean annual home-range size for Osceola females (x = 30.3 km2 ± 4.0 [SE], n = 53) varied little seasonally or annually and was almost half that of Okefenokee females (55.9 km2 ± 6.9, n = 69; Z = −2.47, P = 0.014). In contrast, radiocollared females in Okefenokee expanded their home ranges during years of poor black gum production. That expansion was most apparent between autumn 1998 and 1999, when mean home-range size for Okefenokee females increased from 14.5 km2 to 78.4 km2, respectively, and included a larger proportion of upland areas open to sport hunting. As a result, 5 females were harvested in the Okefenokee study area during the 1999 bear hunting season compared with only 7 harvested from 1996 to 1998. Home ranges of adult female bears were located in areas with disproportionately high loblolly bay (Gordonia lasianthus) and gum-bay-cypress (Taxodium spp.) vegetation associations in Okefenokee and gum-bay-cypress associations in Osceola. The pine vegetation association ranked lower than most other associations within the home ranges of bears in both study areas even though much of the summer and autumn diets of bears included food items found almost exclusively in pine. Sixteen mortalities of radiocollared bears were documented in Okefenokee; hunting accounted for 11 (68.8%) of these deaths. The annual survival rate of radiocollared males in Okefenokee was 0.71 (95% CI = 0.53-0.88) whereas survival of females in Okefenokee was higher (Z = 18.87, P < 0.001) at 0.89 (95% CI = 0.83-0.95). The survival rate for females in Osceola was 0.97 (95% CI = 0.92-1.00). Overall, 67 bears (51M:16F) were killed by hunters in the Okefenokee study area from 1995 to 1999. Based on all radiocollared bears in Okefenokee, many of which resided within areas closed to hunting, we estimated an annual harvest rate of 0.22 (95% CI = 0.03-0.37) for males and 0.07 (95% CI = 0.01-0.12) for females. When we excluded those bears that were not in areas open to hunting, however, the annual harvest rate rose to 0.37 (95% CI = 0.07-0.58) for males and 0.39 (95% CI = 0.09-0.58) for females. Following a black gum shortage in autumn 1995, only 1 of 15 radiocollared females in Okefenokee produced cubs in winter 1996. That low reproductive rate was in contrast to winter 1997, which followed heavy black gum production, when 21 of 22 radiocollared females produced cubs. Reproductive output was more consistent in the Osceola study area, with 46 cubs being produced from 8, 5, and 9 litters in 1997, 1998, and 1999, respectively. To estimate population size, we maintained 88 and 94 barbed-wire hair traps during 1999 in the Okefenokee and Osceola study areas, respectively. Using DNA collected at the hair traps, mark-recapture models produced estimates of 71 bears (95% CI = 59–91) in Okefenokee and 44 bears (95% CI = 40–57) in the Osceola study area during 1999. The estimated densities in the Okefenokee and Osceola study areas were 0.12 and 0.14 bears/km2, respectively. Alternative density estimates based on the amount of time bears spent within study area boundaries were similar (0.11 and 0.14 bears/km2 on Okefenokee and Osceola, respectively). We used a population model to estimate the effect of harvest in the Okefenokee bear population. Excluding harvest, bears at Osceola experienced higher average annual population growth (Λ = 1.184 ± 0.002) than those at Okefenokee (1.064 ± 0.002; t18 = 3.93, P = 0.001), most likely due to protection from hunting and higher recruitment. Including the effects of emigration and immigration, we estimated an average annual sustainable harvest at Okefenokee of approximately 9 bears (12.6%), which was slightly less than the average 1995–1999 annual harvest of 9.4. That level of hunting in Okefenokee is sustainable but likely represents the highest exploitation rate in the region. Our mark-recapture data from Osceola suggest a high dispersal rate by subadult bears, and our population modeling data support this hypothesis; we documented bears in Okefenokee that originated from Osceola but not the reverse. We speculate that bears from the interior of the Okefenokee National Wildlife Refuge (ONWR), and to some extent northern Florida, served as a source to the population sink caused by hunting mortality in Okefenokee and in the surrounding Georgia counties. Corn from deer feeders was the most probable reason for smaller home-range sizes and greater body masses and reproductive output at Osceola. Changes in management to eliminate or reduce baiting for deer with corn would negatively affect the Osceola bear population. On Okefenokee, sporadic black gum and palmetto production influenced harvest rates and cub production and, thus, governed bear population dynamics. The U.S. Fish and Wildlife Service (USFWS) concluded in 1998 that listing the Florida black bear as threatened under the Endangered Species Act of 1973 was not warranted. That decision was largely based on the stability and protection afforded to a few subpopulations within the range of the subspecies, which includes the Okefenokee-Osceola subpopulation; our results support that conclusion. However, we suggest that metapopulation processes among the various subpopulations be given greater consideration, with the ultimate goal of managing the subspecies as a unit rather than as an assemblage of independent components. Our study illustrates the importance of travel corridors for maintaining metapopulation processes.

Food Habits of Brown Bears (Ursus arctos) in the Cantabrian Mountains, Spain

The diet of the European brown bear ( Ursus arctos ) was studied in the Cantabrian Mountains, Spain, by analyzing the frequency of occurrence and percent volume of 929 feces collected 1983–1988. Plant material was the predominant food during spring and summer (84.1 and 44.8% of total volume, respectively) until more nutritious foods became available. During autumn and winter, hard mast formed the greatest part of the diet constituting 61.5 and 49.9% of the total volume, respectively. Livestock and wild ungulates were supplementary foods for bears, usually obtained by scavenging rather than predation. Insects were consumed year-round, ranging from 19.5% volume in summer to 0.1% in winter. Remnant deciduous forests and upland creek drainages were prime feeding areas of bears.

BAIT STATIONS, HARD MAST, AND BLACK BEAR POPULATION GROWTH IN GREAT SMOKY MOUNTAINS NATIONAL PARK

Abstract Bait-station surveys are used by wildlife managers as an index to American black bear (Ursus americanus) population abundance, but the relationship is not well established. Hard mast surveys are similarly used to assess annual black bear food availability, which may affect mortality and natality rates. We used data collected in Great Smoky Mountains National Park (GSMNP) from 1989 to 2003 to determine whether changes in the bait-station index (ΔBSI) were associated with estimated rates of bear population growth (λ) and whether hard mast production was related to bear visitation to baits. We also evaluated whether hard mast production from previous years was related to λ. Estimates of λ were based on analysis of capture–recapture data with the Pradel temporal symmetry estimator. Using the Akaikes Information Criterion (AIC), our analysis revealed no direct relationship between Δ BSI and λ. A simulation analysis indicated that our data were adequate to detect a relationship had one existed. Model fit was marginally improved when we added total oak mast production of the previous year as an interaction term suggesting that the BSI was confounded with environmental variables. Consequently, the utility of the bait-station survey as a population monitoring technique is questionable at the spatial and temporal scales we studied. Mast survey data, however, were valuable covariates of λ. Population growth for a given year was negatively related to oak mast production 4 and 5 years prior. That finding supported our hypothesis that mast failures can trigger reproductive synchrony, which may not be evident from the trapped sample until years later.

The influence of a small sanctuary on survival rates of black bears in North Carolina

Sanctuaries for black bears (Ursus americanus) were established in North Carolina in 1971 to protect breeding females and provide surplus bears for hunting. To test the efficacy of this management technique, we studied survival rates of 51 black bears captured from 1982-89 in and around Harmon Den Bear Sanctuary, North Carolina. We determined the proportion of daily locations that each bear spent off the sanctuary (POFF). We fit a Cox proportional hazard model to these data to determine which combinations of sex, age, and POFF most affected survival. The model selection procedure selected a 2 covariate model of POFF and age as the best model. This model and the mean POFF for each sex and age group indicated adult females had highest survival rates, followed by adult males, subadult females, and subadult males. Harmon Den Bear Sanctuary appears to protect adult females and produces subadult bears for recreational hunting.

Homing of Black Bears in the Great Smoky Mountains National Park

The interactions between nuisance black bears (Ursus americanus) and people create many problems in the Great Smoky Mountains National Park (GSMNP or Park) as well as in other areas of North America. These interactions necessitate management guidelines determined from biological data about the bears. Personnel of the National Park Service (NPS) have handled nuisance bears by moving them to various areas within the Park, transporting them to state wildlife management areas or in some instances destroying habitually nuisance animals. Generally, bears have been destroyed only when other management procedures failed and the animal was judged to present a potential danger to Park visitors.

Spatial response of American black bears to prescribed fire in northwest Florida

Abstract Little is known about the effects of prescribed burning on American black bears (Ursus americanus) in the Southeastern Coastal Plain. In Florida, Eglin Air Force Base is home to 1 of 8 relatively disjunct populations of black bears (U. a. floridanus) in the state. Prescribed burning has been used on Eglin since the late 1980s to reduce the dense oak (Quercus spp.) midstory that occupies the longleaf pine (Pinus palustris)–wiregrass (Aristida beyrichiana) community. We studied black bear habitat use during 1994–96 to determine if temporal and spatial relationships existed between prescribed fire and black bear habitat use from 9 years of burning data. Within all habitat types, our results showed that black bears used unburned areas more than burned areas, both annually and seasonally. Among burned areas, black bear use was greatest in 3- and ≥5-year-old burns, both annually and seasonally, for most habitat types. Our results are consistent with published reports on timing of peak soft mast production following prescribed fire, and we conclude that higher use of particular burn ages was related to production of several soft-mast species. We suggest that longer burning cycles be applied within and adjacent to important habitats, like riparian zones, in the Southeastern Coastal Plain. Planning for juxtaposition of various successional post-fire stages is the best approach for managing habitats to maintain cover and availability of primary bear foods and effectively minimize the area needed to satisfy the needs of black bears.