Estimating Grizzly and Black Bear Population Abundance and Trend in Banff National Park Using Noninvasive Genetic Sampling

We evaluated the potential of two noninvasive genetic sampling methods, hair traps and bear rub surveys, to estimate population abundance and trend of grizzly (Ursus arctos) and black bear (U. americanus) populations in Banff National Park, Alberta, Canada. Using Huggins closed population mark-recapture models, we obtained the first precise abundance estimates for grizzly bears ( = 73.5, 95% CI = 64–94 in 2006;  = 50.4, 95% CI = 49–59 in 2008) and black bears ( = 62.6, 95% CI = 51–89 in 2006;  = 81.8, 95% CI = 72–102 in 2008) in the Bow Valley. Hair traps had high detection rates for female grizzlies, and male and female black bears, but extremely low detection rates for male grizzlies. Conversely, bear rubs had high detection rates for male and female grizzlies, but low rates for black bears. We estimated realized population growth rates, lambda, for grizzly bear males ( = 0.93, 95% CI = 0.74–1.17) and females ( = 0.90, 95% CI = 0.67–1.20) using Pradel open population models with three years of bear rub data. Lambda estimates are supported by abundance estimates from combined hair trap/bear rub closed population models and are consistent with a system that is likely driven by high levels of human-caused mortality. Our results suggest that bear rub surveys would provide an efficient and powerful means to inventory and monitor grizzly bear populations in the Central Canadian Rocky Mountains

Iron Behaving Badly: Inappropriate Iron Chelation as a Major Contributor to the Aetiology of Vascular and Other Progressive Inflammatory and Degenerative Diseases

The production of peroxide and superoxide is an inevitable consequence of aerobic metabolism, and while these particular "reactive oxygen species" (ROSs) can exhibit a number of biological effects, they are not of themselves excessively reactive and thus they are not especially damaging at physiological concentrations. However, their reactions with poorly liganded iron species can lead to the catalytic production of the very reactive and dangerous hydroxyl radical, which is exceptionally damaging, and a major cause of chronic inflammation. We review the considerable and wide-ranging evidence for the involvement of this combination of (su)peroxide and poorly liganded iron in a large number of physiological and indeed pathological processes and inflammatory disorders, especially those involving the progressive degradation of cellular and organismal performance. These diseases share a great many similarities and thus might be considered to have a common cause (i.e. iron-catalysed free radical and especially hydroxyl radical generation). The studies reviewed include those focused on a series of cardiovascular, metabolic and neurological diseases, where iron can be found at the sites of plaques and lesions, as well as studies showing the significance of iron to aging and longevity. The effective chelation of iron by natural or synthetic ligands is thus of major physiological (and potentially therapeutic) importance. As systems properties, we need to recognise that physiological observables have multiple molecular causes, and studying them in isolation leads to inconsistent patterns of apparent causality when it is the simultaneous combination of multiple factors that is responsible. This explains, for instance, the decidedly mixed effects of antioxidants that have been observed, etc...Comment: 159 pages, including 9 Figs and 2184 reference

Using genetics in the conservation management of the American black bear (Ursus americanus) in Missouri

By the early 1900s, black bears were believed to be almost extinct in Missouri and Arkansas, presumably due to extensive logging and overharvest. To reestablish Arkansas populations, the Arkansas Game and Fish Commission conducted a translocation program from 1958 to 1968, moving 254 bears from Minnesota and Manitoba, Canada, to the Ozark and Ouachita National Forests. This remains one of the most successful large mammal translocations ever conducted, and the Arkansas population grew rapidly into the thousands. However, bear sightings and nuisance reports suggested that 50 years after the translocations, populations in Missouri were small, and densities were low. We conducted a spatially explicit genetic capture-recapture study to estimate the size and density of the black bear population in south-centralMissouri.We genotyped hair samples collected over two years using 15 microsatellite loci and estimated the population size at 279 ± 54 (SE) and the density at 1.7 bears/km2. To infer the source of bears colonizing Missouri, we analyzed the resulting genotypes in the Bayesian clustering program STRUCTURE along with genotypes from Arkansas, Oklahoma, and source populations. The results revealed unique genetic clusters in the Ouachitas, the Ozarks, and the source populations and found that Missouri bears were divided between those that clustered with the Ozarks and a unique cluster. The presence of the unique cluster in Missouri supports the hypothesis that black bears in the Missouri Ozarks were not extirpated but were reduced to very low densities during European settlement and have subsequently become admixed with bears that trace their ancestry to the reintroduction. While some might suggest that the unique Missouri population should be designated as a separate management unit, we caution that this might not be beneficial to the preservation of the Missouri bear population as we have no evidence that it is ecologically or geographically distinct, it has low genetic diversity, and the genetic differentiation may not be related to adaptive differences