Wildlife managers at Kenai Fjords (KEFJ) National Park, Alaska, are developing a comprehensive bear management plan. An important first step in this plan is to establish a baseline of bear abundance and inventory approaches for future monitoring efforts. In this study we use non-invasive genetic sampling and DNA-based capture–mark–recapture (CMR) analysis to estimate abundance of American black bears (Ursus americanus) using coastal habitats in the park. We used 2 multi-session CMR models in program MARK and 2 continuous-occasion models specifically designed for DNA-based capture data in the programs CAPWIRE and BAYESN. The latter 2 models maximize data from non-invasive sampling by allowing the entire sampling period to be considered a single continuous capture–mark–recapture occasion. Although all models yielded similar point estimates of population size, confidence intervals varied widely among methods. CAPWIRE yielded the most precise estimates of bear abundance. The number of bears estimated in each KEFJ bay ranged from 73 in the least populated to 324 in the most populated bay. Overall, the continuous-occasion CMR models provided the best estimates with our dataset, and we found that this approach offers a practical option when trapping seasons are constrained by biological or logistical factors.

The Japanese brown bear (Ursus arctos yesoensis) lives only on Hokkaido Island, where human–bear conflicts are common, but the status of bear populations are unknown. The Shiretoko Peninsula in northeastern Hokkaido supports one small population. The distal half of the 1,000-km² peninsula has been protected as a wildlife reserve since the 1980s. Reduction in harvest and frequent sightings of bears suggests that the population has been increasing since that time. On the other hand, human–bear conflicts and management kills are not uncommon in the proximal half, and occur occasionally even in the protected area. Also, unreported harvest might be substantial. Lacking unbiased survival data from marked bears, we modeled the Shiretoko population using female-only matrix models in a series of “what if?” scenarios that we believe bounded reality. We assumed, alternatively, that true mortality equaled reported kills (best case) and that it double reported kills (worst case). During 1985–2004, known mortality was 12.9 animals/year (1.9 adult females/year), and we doubled this for our scenarios that assumed the detection of mortality was 50%. We estimated reproductive rates by monitoring marked and unmarked — but individually recognizable — females, and estimating transition rates among reproductive states. From 1990 to 2004, 13 identifiable females were observed in west-central Shiretoko for a total of 67 female-years, with 51 unduplicated cubs. Mean litter size was 1.594 (n = 32), and reproductive rate was estimated as 0.604 cubs/female/year (0.302 for female cubs). Our model suggested that if the female population size (N_f) had been 200, it would have been increasing regardless of whether known mortality was 50% or 100% of true mortality. Under the assumption of N_f = 150 and a mortality-detection rate of 50% (worst case), projections suggested the possibility of either an increase or decline (95% CI of λ = 0.986–1.150). The current harvest rate remains unknown because the population size remains unknown, but we could not reject the possibility that current harvest rates are beyond the sustainable level. We call for more efforts to closely monitor the population and harvest, and to promote preventive measures to reduce human–bear conflicts.

I examined the sex and age at death of Asiatic black bears (Ursus thibetanus) killed by sport hunters or during nuisance incidents in 2 neighboring mountain ranges (Kitakami Highland [KH] and Ohwu Mountains [OH]) in northern Honshu, Japan. Between 1993 and 2000, 1,005 bears were killed in these areas (361 nuisance kills, 644 sport-hunting kills). Nuisance bear removals were 1.3 times greater in KH than in OM. Males removed during nuisance incidents tended to be younger in OM than in KH; older males as well as females made up proportionately more of KH nuisance removals. The monthly nuisance removals varied widely by year in both areas, with the largest yearly variation in September in KH and August–September in OM. Female deaths accounted for much of the increase in nuisance kills in KH during September. Both sexes contributed to the increase in OM nuisance kills during August and September. The number of bears killed by sport hunting in KH was 4.7 times larger than in OM. OM terrain is steep and has deep snow during winter, which largely restricts human settlement and agriculture to the eastern edge of this area. Conversely, KH is gently sloping with less snow cover, allowing human settlement and agriculture to disperse more widely into mountainous bear habitat. Such differences in habitat conditions likely influence the degree of human–bear conflict and hunting pressure. Because the population was isolated and many females were removed in KH, I recommend more careful monitoring of the population by examining the sex and age structure of harvested animals relative to densities and real measures of hunting effort.

A relict population of unique desert dwelling brown bears (Ursus arctos) inhabits a series of remote oases along the southern portion of the Great Gobi Strictly Protected Area in Mongolia. Little is known about these bears, which may number as few as 25 animals. We used noninvasive genetic techniques in an attempt to estimate minimum population size, determine sex ratios, and evaluate genetic diversity and degree of isolation between population centers. Between 1996 and 1998 we collected 200 hair samples using hair-traps from rub posts and attempted to amplify 6 microsatellite loci for 75 samples with 3 or more follicles. Microsatellite amplification rates were low (63%), and 3 loci were monomorphic. Complete genotypes could be obtained for only 28 samples, which provided a minimum count of 8 bears. Observed heterozygosity (0.29) and average number of alleles (2) were very low compared to other brown bear populations. Genetic data were obtained for only 2 of the 3 population centers, and sample sizes were not large enough to accurately evaluate sex ratio or levels of isolation. A 263 base-pair segment of the mitochondrial DNA control region was sequenced for 3 bears and a single control region haplotype was obtained. This haplotype was identical to a previously published haplotype for the Gobi bear, and earlier work has shown that this haplotype is closely related to brown bear haplotypes from Pakistan. Future genetic analyses that attempt to use hair or fecal samples will need to increase the number of loci to provide sufficient resolving power for individual identification and should attempt to collect fresher samples to increase success rates. The detection of very low levels of genetic diversity supports the hypothesis that this population is very small and isolated from other brown bear populations. Further studies of the Gobi bear and conservative management actions are greatly needed.

Of American black bears (Ursus americanus) killed by vehicles in Florida from 1976 to 2003, 45% were from the population in central Florida centered in Ocala National Forest (ONF). This area contains 8 of the state's 15 most severe roadkill areas. More bears were killed along State Road 40 (SR-40), which bisects this population, than along any other road in the state. Interest in widening this road provided an opportunity to document bear movements and the frequency with which they crossed SR-40 when average annual daily traffic (AADT) volume was at each of two levels: 5,100 vehicles per day (vpd) in ONF and 15,700 vpd in the adjacent community of Lynne. We analyzed the locations of 86 radiocollared bears (33 F∶40 M in ONF and 13 F in Lynne) and monitored them 1–3 times/week from May 1999 through May 2003. Forty-eight bears crossed SR-40 a minimum of 388 times. ONF female bears were 2.9 times more likely than Lynne females to cross SR-40, but this rate was only marginally significant. ONF male bears were 4.3 times more likely to cross SR-40 than ONF females and 12.3 times more likely to cross than were Lynne females. We documented the mortality of 7 radiocollared bears by vehicles, 4 males in ONF and 3 females in Lynne. There were no deaths of ONF females due to vehicular collisions, but female bears in Lynne died from vehicle collisions at near the rate of ONF male bears. We recommend that a minimum of 6 crossing structures be incorporated along this highway to reduce the effect of highway expansion on the Ocala population of Florida black bears.

During 1995–2006 research projects in Florida and Kentucky, USA, we captured 191 (72 F∶119 M) American black bears (Ursus americanus) 251 times using modified Aldrich spring-activated snares. In our modification, the swivel at the base of the foot loop was attached to 2 cables that ran in opposite directions and were anchored to trees. Shortening the free cable to only the foot loop limited the area in which the captured animal could move and provided more options for snare placement. This smaller area reduced the distance that a captured bear could run when attempting to charge or flee, which made immobilization easier. This modification also prevented the bear from climbing or reaching the anchor trees. Using this modification also increased available trap sites by allowing use of trees that would have been inadequate as a single anchor because of low branches, forked or leaning trunks, proximity to hazards, or small size. We believe this alternative anchor method is an improvement, particularly for snares set on trails, because they often require longer anchor cables to reach the desired location. This anchor method should work with any snare trigger and for any species that is trapped using an anchored foot snare.

Wildlife researchers and managers have been using Aldrich foot snares to capture American black bears (Ursus americanus) and grizzly bears (U. arctos) for decades. Recently, failures have been reported in snare cable assemblies, resulting in escapes of both black and grizzly bears. We tested different configurations of snare cable and hardware using a hydraulic pull machine. Snare foot loops constructed with compression sleeves or Crosby® clips torqued to 20.3 newton-meters (N-m) consistently exceeded minimum strength requirements for use on large bears (>16.8 kilonewton [kN]). In our tests, anchor sections of snares using compression sleeves and 0.794 cm swivels never failed below 30 kN. It is important to use robust, manufacturer-rated hardware and precise methodology when building snare cables to achieve consistent holding strength. The use of substandard components and improper torquing of clamps can result in failure of the snare endangering both bears and capture personnel.

Although the Chinese government and international organizations have spent millions of dollars estimating the population size of giant pandas (Ailuropoda melanoleuca), the outcomes of such surveys have been debated because the methods used had uncertain ability to differentiate individuals. Our work in Wanglang Reserve was the first attempt at using fecal microsatellite analysis to enumerate giant pandas (Zhan et al. 2006), and we found the molecular enumeration for the reserve more than doubled that estimated in the third National Survey. Recently, Garshelis et al. (2008) challenged our DNA estimate on the grounds that our study lacked geographic closure and that genotyping errors confounded our results. We challenge both assertions. First, we realize the violation of the assumption of geographic closure is a common problem for noninvasive genetic capture–recapture studies; therefore, we tried in our methodology to minimize geographic closure effects. We conclude that immigration did not greatly affect our main conclusions because of a geographic barrier circling the study area, the limited mobility of giant pandas, and the same sampling intensity was applied to the whole study area. Second, internationally accepted standards were applied to our molecular analysis and appropriate laboratory procedures were taken to produce reliable genotypes. Although we did not report an estimate of genotyping error in our previous work (Zhan et al. 2006), genotyping error rates have now been estimated, but are still pending publication. Based on the Wanglang result, we raised the possibility that there might be more giant pandas in the wild than previously thought. If our prediction is shown to be correct, we do not believe the new estimate will serve to downgrade current endangered status of the giant panda, because population numbers remain very low and panda habitats are fragmented (even more so since the 2008 earthquake). For future conservation of giant pandas, we suggest more attention should be paid to panda habitat conservation, including habitat restoration at the landscape scale and scientific research on detailed population processes.

We report the discovery of a partial skeleton of the oldest spectacled bear (Tremarctos ornatus) known to date. It was found at 2,950 m elevation in the Chaquil cave, in the Departamento de Amazonas, north central Peru. Its age, as determined by accelerated mass spectrometry conventional radiocarbon dating, was, within 50 years, 5,980 years before present (YBP). After a standard correction for Holocene irregularities of atmospheric ¹⁴C (carbon 14) levels, this conventional radiocarbon age translates into a calendar age of about 6,790 years before present. Anatomical features of the skull shows no significant differences from extant spectacled bears. Comparative analysis of Chaquil remains with those of modern specimens revealed some intraspecific variation at the sagittal crest, mandibular ramus and symphysis, masseteric crest, and coronoid process. We suggest that the extremely worn teeth, with the pulpar cavity exposed in the sub-fossil, are related to a primarily carnivorous diet.

We report on a young male, cinnamon-phase American black bear (Ursus americanus) that was collected in northwestern Nebraska on 12 May 2008. This specimen represents the first black bear taken in Nebraska since 1907. Cranial characteristics and mass of the individual indicated a 15–16 month old bear. This bear may have dispersed from the Laramie Mountains in southeastern Wyoming along the North Platte River into western Nebraska. This record adds to the growing number of cases where large carnivores are reinvading previously occupied territory in the Great Plains. These reinvasions potentially have broad ecological implications to local prey populations and overall biodiversity.