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The 3 spotted owl (Strix occidentalis) subspecies in North America (i.e., northern spotted owl [S. o. caurina], California spotted owl [S. o. occidentalis], Mexican spotted owl [S. o. lucida]) have all experienced population declines over the past century due to habitat loss and fragmentation from logging. Now, the emerging influences of climate change, high-severity fire, and barred owl (Strix varia) invasion also appear to be synergistically and differentially affecting population trends of each subspecies. Our objective was to review the existing literature on the spotted owl to describe historical and emerging threats and whether those threats have been adequately examined for each subspecies. Using 527 publications from a Web of Science search of the literature from 1900-2015, we statistically evaluated the emphasis placed on each subspecies regarding 4 influences: mechanical tree removal, fire, climate change, and barred owl invasion. There were 98 papers that explicitly examined the effects of !1 of these influences. Most of these papers were focused on the northern spotted owl, and for all 3 subspecies, most papers examined short-term effects only. We used our results to identify significant information gaps relative to historical and emerging threats. Commercial timber harvesting remains a potential threat for all 3 spotted owl subspecies, but effects from forest thinning may be increasing because of the heightened emphasis on fuels reduction and forest restoration treatments on public lands. Owl response to mechanical tree removal, especially forest thinning, remains understudied. Climate change also may threaten all 3 subspecies. Changes in climate likely affect survival and reproduction of spotted owls and their prey, and alter habitat availability by affecting disturbance regimes and vegetation composition and succession, but little empirical information is available describing specific responses to climate change. The literature on response to high-severity fire is sparse for some subspecies, primarily short-term in nature, and not consistent. Barred owl invasion is a major threat to the northern spotted owl and the California spotted owl but does not currently threaten the Mexican spotted owl. Rigorous research on the response of spotted owls to all factors influencing population change, particularly for the Mexican spotted owl, is needed. The most useful information for predicting owl response to these threats stems primarily from long-term studies of owl demography. The lack of such studies within the range of the Mexican spotted owl greatly limits our understanding of its population dynamics and our ability to predict the effects of various threats on Mexican spotted owl populations. For all 3 subspecies, we encourage long-term studies of their responses to threats, using uniquely marked owls across large spatial extents to account for spatiotemporal variability in ecological conditions within and among subspecies. Ó 2018 The Wildlife Society.

Monitoring our natural resources will increasingly rely on genetic tools in order to understand and respond to invasive species, habitat degradation, fragmentation, disease, or climate-related changes. In recent years, the rapidly evolving field of genetic monitoring has seen explosive growth in sampling methods, genetic markers, and analytical approaches designed to estimate a wide range of parameters from connectivity to population growth rates. Some of these methods have taken root and now dominate particular aspects of population assessment and monitoring, whereas others have seen less success in real-world applications. To aid managers and researchers with limited genetics experience, we developed a web-based resource to help them identify which, if any, molecular genetic methods would be appropriate for population assessments or monitoring. The site was developed in cooperation with a team of experts in fields such as evolutionary biology, demographic parameter estimation, and exotic species detection to provide a broad, dynamic, and easily understood resource with limited jargon. The site also provides distilled examples from the recent literature, along with contact information for experts in various techniques. The website, Genetic Monitoring for Managers, is now available at http://alaska.fws.gov/gem/mainPage_1.htm.

Conservation efforts for tree-and snag-roosting bats are challenging because roost sites are difficult and costly to locate. We assessed the ability of scent detection dogs to locate bat roosts using controlled field experiments conducted at 2 sites in northern Arizona, USA, during July and August of 2007, with small bags of bat guano and known bat roosts. Scent detection dogs correctly detected 79% of guano bags and 29% of known bat roosts; but, when searching during shorter time periods for roosts only, dogs correctly detected 77% of known roosts. Factors affecting detection of guano bags included bag height and mass. Factors affecting detection of roosts included height, size of the bat colony, and air temperature. Rest breaks and competition between dogs apparently increased their success rate in finding roosts. Using a scent detection dog to locate roosts was similar in cost to radiotelemetry; however, the use of a scent detection dog was less invasive because the use of dogs precluded the need to capture and radiotag bats. Important considerations influencing the efficacy of using scent detection dogs include training and transportation costs, and skill level of dog handlers. Although some factors limit the ability of scent detection dogs to accurately locate roosts, dogs in our study approximated the roost location to within a 30-m radius, which may be sufficient to protect these areas during management activities. If managers have the ability within an area to retain all large-diameter snags that have bat roost characteristics, then scent detection dogs will likely not provide adequate added value to warrant their survey costs. However, scent dogs could be important for locating roosts of species that are imperiled or of conservation concern. Ó 2015 The Wildlife Society.