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Context Researchers and managers often use DNA analysis and remote photography to identify cryptic animals and estimate abundance. Remote video cameras are used less often but offer an increased ability to distinguish similar-looking individuals as well as to observe behavioural patterns that cannot be adequately captured with still photography. However, the use of this approach in species with minimally distinguishing marks has not been tested. Aims To determine the utility and accuracy of distinguishing characteristics of American black bears, Ursus americanus, observed on remote video for identifying individuals in an open population. Methods We compared individuals identified on video with individuals and their sex identified by DNA analysis of hairs collected from hair traps visited by the bears. Key results We found that remote video could be used to determine the number of male and female black bears sampled by the video cameras. Specifically, we matched 13 individual bear genotypes with 13 video identifications, one genotype for each individual. We correctly matched ~82% of video identifications with all 38 genotypes collected from hair traps. Conclusions We demonstrated that distinguishing characteristics of a cryptic animal in remote video can be used to accurately identify individuals. Remote video complements genetic analysis by providing information about habitat use and behaviour. Implications When remote video cameras can be used to identify individuals, a wealth of other information will subsequently be obtained. Multi-year video-based studies can show sex ratios, and relative physical condition; shed light on fine-scale habitat use, such as when and where animals feed and what they eat; and display social interactions and rare behaviours.

Camera or genetic data are increasingly used to estimate wildlife abundance and density. We integrated video camera data with genetic data over 7 years to estimate annual age‐structured apparent survival of American black bears (Ursus americanus). We identified 70 individuals through meticulous scrutiny of 7531 video captures, cross‐referenced with 721 genetic captures from hair samples concurrently collected from stations in view of cameras. We used the Cormack–Jolly–Seber model in Program Mark to estimate annual age‐structured apparent survival for yearling males, yearling females, 2+ year‐old males, and 2+ year‐old females. We manually calculated cub survival. We compared parameter estimates based on combined video and genetic data with those based on only genetic data. Combining video and genetic data provided a means to test video‐based identification accuracy, which was highest for females (97%–100%). Annual apparent survival was highest for yearling females (φ = 0.92, SE = 0.07), followed by 2+ year‐old females (φ = 0.88, SE = 0.05), 2+ year‐old males (φ = 0.84, SE = 0.06), and yearling males (φ = 0.80, SE = 0.14). Annual cub survival (φ = 0.86, SE = 0.07) was likely biased because we could not account for mortality that occurred in‐den through early spring. Annual apparent survival and recapture probabilities derived from only genetic data were lower than those derived from combined video and genetic data. Our finding that noninvasive data can be used to estimate annual age‐structured apparent survival of a species with relatively indistinct traits is broadly relevant to wildlife research and conservation.

SynopsisPreliminary data from the National Institute of Mental Health – Clinical Research Branch Collaborative Program on the Psychobiology of Depression dealing with the human growth hormone (hGH) response to the Insulin Tolerance Test (ITT) during the pre-treatment (drug-free) period of the study are presented in this paper. Data are reported for 54 unipolar depressed, 21 bipolar depressed, and 40 normal control subjects, who represent approximately 50% of the final subject sample to be studied. In this population the unipolar depressed subjects showed a significantly greater resistance to insulin-induced hypoglycaemia than bipolar and control subjects. After applying the inclusion/exclusion criteria necessary to interpret hGH responses accurately, the data from only 54 subjects were acceptable. Mean peak hGH concentrations were not significantly different among the three groups. There was, however, a significant difference in the distributions of the hGH peak response, with the bipolar depressed population demonstrating greater variability in response than unipolar and control populations. These findings are discussed as they relate to previous reports and theoretical considerations.

Many North American river otter (Lontra canadensis) populations are threatened or recovering but are difficult to study because they occur at low densities, it is difficult to visually identify individuals, and they inhabit aquatic environments that accelerate degradation of biological samples. Single nucleotide polymorphisms (SNPs) can improve our ability to monitor demographic and genetic parameters of difficult to study species. We used restriction site associated DNA (RAD) sequencing to discover 20,772 SNPs present in Montana, USA, river otter populations, including 14,512 loci that were also variable in at least one other population range-wide. After applying careful filtering criteria meant to minimize ascertainment bias and identify high quality, highly heterozygous (H o = 0.2-0.50) SNPs, we developed and tested 52 independent SNP qPCR genotyping assays, including 41 that performed well with diluted DNA. The 41 loci provided high power for population assignment tests with only 1 misassignment (1.6 %) between closely neighboring populations. Our SNPs showed high power to differentiate individuals and assign them to population of origin, as well as strong concordance of genotypes from high and diluted concentrations of DNA, and between original RAD and the SNP qPCR array.