Age-specific survival rates, causes of death, and allowable take of golden eagles in the western United States.

In the United States, the Bald and Golden Eagle Protection Act prohibits take of golden eagles (Aquila chrysaetos) unless authorized by permit, and stipulates that all permitted take must be sustainable. Golden eagles are unintentionally killed in conjunction with many lawful activities (e.g., electrocution on power poles, collision with wind turbines). Managers who issue permits for incidental take of golden eagles must determine allowable take levels and manage permitted take accordingly. To aid managers in making these decisions in the western United States, we used an integrated population model to obtain estimates of golden eagle vital rates and population size, and then used those estimates in a prescribed take level (PTL) model to estimate the allowable take level. Estimated mean annual survival rates for golden eagles ranged from 0.70 (95% credible interval = 0.66-0.74) for first-year birds to 0.90 (0.88-0.91) for adults. Models suggested a high proportion of adult female golden eagles attempted to breed and breeding pairs fledged a mean of 0.53 (0.39-0.72) young annually. Population size in the coterminous western United States has averaged ~31,800 individuals for several decades, with λ = 1.0 (0.96-1.05). The PTL model estimated a median allowable take limit of ~2227 (708-4182) individuals annually given a management objective of maintaining a stable population. We estimate that take averaged 2572 out of 4373 (59%) deaths annually, based on a representative sample of transmitter-tagged golden eagles. For the subset of golden eagles that were recovered and a cause of death determined, anthropogenic mortality accounted for an average of 74% of deaths after their first year; leading forms of take over all age classes were shooting (~670 per year), collisions (~611), electrocutions (~506), and poisoning (~427). Although observed take overlapped the credible interval of our allowable take estimate and the population overall has been stable, our findings indicate that additional take, unless mitigated for, may not be sustainable. Our analysis demonstrates the utility of the joint application of integrated population and prescribed take level models to management of incidental take of a protected species.

Video capsule endoscopy in the emergency department: a prospective study of acute upper gastrointestinal hemorrhage.

STUDY OBJECTIVE: Video capsule endoscopy has been used to diagnose gastrointestinal hemorrhage and other small bowel diseases but has not been tested in an emergency department (ED) setting. The objectives in this pilot study are to demonstrate the ability of emergency physicians to detect blood in the upper gastrointestinal tract with capsule endoscopy after a short training period, measure ED patient acceptance of capsule endoscopy, and estimate the test characteristics of capsule endoscopy to detect acute upper gastrointestinal hemorrhage. METHODS: During a 6-month period at a single academic hospital, eligible patients underwent video capsule endoscopy (Pillcam Eso2; Given Imaging) in the ED. Video images were reviewed by 4 blinded physicians (2 emergency physicians with brief training in capsule endoscopy interpretation and 2 gastroenterologists with capsule endoscopy experience). RESULTS: A total of 25 subjects with acute upper gastrointestinal hemorrhage were enrolled. There was excellent agreement between gastroenterologists and emergency physicians for the presence of fresh or coffee-ground blood (0.96 overall agreement; κ=0.90). Capsule endoscopy was well tolerated by 96% of patients and showed an 88% sensitivity (95% confidence interval 65% to 100%) and 64% specificity (95% confidence interval 35% to 92%) for the detection of fresh blood. Capsule endoscopy missed 1 bleeding lesion located in the postpyloric region, which was not imaged because of expired battery life. CONCLUSION: Video capsule endoscopy is a sensitive way to identify upper gastrointestinal hemorrhage in the ED. It is well tolerated and there is excellent agreement in interpretation between gastroenterologists and emergency physicians.

Landscape characteristics influence morphological and genetic differentiation in a widespread raptor (Buteo jamaicensis).

Landscape-scale population genetic structure in vagile vertebrates was commonly considered to be a contradiction in terms whereas recent studies have demonstrated behaviour and habitat associated structure in several such species. We investigate whether landscape features influence morphological and genetic differentiation in a widespread, mobile raptor. To accurately describe genetic differentiation associated with regional landscape factors, we first investigated subspecies relationships at a continental scale. We used 17 microsatellite loci and five morphological measurements to investigate differentiation between eastern and western subspecies of red-tailed hawks (Buteo jamaicensis) and to identify patterns between differentiation and habitat within western North America. Bayesian and frequency-based analyses of microsatellite data revealed clear distinctions between B. j. borealis (eastern) and B. j. calurus (western) samples. Furthermore, hawks sampled in Texas were stouter than those collected from the Rocky Mountains and farther west. Among western samples, birds from the Great Basin, Rocky Mountains, and Washington were significantly different in morphology than those from Oregon and California. We identified a pattern of isolation by distance among western breeding sites around the Sierra Nevada. Given the long-range dispersal capabilities of raptors, this pattern suggests that population-specific habitat preferences, corresponding with habitat breaks between eastern and western slopes of the Sierra Nevada, and/or regionally variable population densities limit migration between the Mediterranean habitat of central California and the xeric habitats of southern California and interior west. We suggest habitat preferences and regionally disparate population densities may play a role in shaping genetic structure in vagile avian taxa.