Suchergebnisse

White-nose syndrome (WNS) has caused dramatic declines of several cave-hibernating bat species in North America since 2006, which has increased the activity of non-susceptible species in some geographic areas or during times of night formerly occupied by susceptible species-indicative of disease-mediated competitive release (DMCR). Yet, this pattern has not been evaluated across multiple bat assemblages simultaneously or across multiple years since WNS onset. We evaluated whether WNS altered spatial and temporal niche partitioning in bat assemblages at four locations in the eastern United States using long-term datasets of bat acoustic activity collected before and after WNS arrival. Activity of WNS-susceptible bat species decreased by 79-98% from pre-WNS levels across the four study locations, but only one of our four study sites provided strong evidence supporting the DMCR hypothesis in bats post-WNS. These results suggest that DMCR is likely dependent on the relative difference in activity by susceptible and non-susceptible species groups pre-WNS and the relative decline of susceptible species post-WNS allowing for competitive release, as well as the amount of time that had elapsed post-WNS. Our findings challenge the generality of WNS-mediated competitive release between susceptible and non-susceptible species and further highlight declining activity of some non-susceptible species, especially Lasiurus borealis, across three of four locations in the eastern United States. These results underscore the broader need for conservation efforts to address the multiple potential interacting drivers of bat declines on both WNS-susceptible and non-susceptible species. ; U.S. Fish and Wildlife Service White-nose Syndrome Grant Program [4500900398]; Fort Drum through the U.S. Army Corps of Engineers' Cooperative Agreement [W9126G-15-2-0005]; Southern Appalachian Cooperative Ecosystems Study Unit Program ; Published version ; Funding for this study was provided by the U.S. Fish and Wildlife Service White-nose Syndrome Grant Program Agreement #4500900398 to the U.S. Geological Survey South Carolina Cooperative Fish and Wildlife Research Unit and the Virginia Cooperative Fish and Wildlife Research Unit. Additional support came from Fort Drum through the U.S. Army Corps of Engineers' Cooperative Agreement W9126G-15-2-0005 and the Southern Appalachian Cooperative Ecosystems Study Unit Program to the Virginia Tech Department of Fish and Wildlife Conservation. We thank P. White and the Wisconsin DNR for providing long-term acoustic data from Wisconsin. Fieldwork assistance was provided by L. Coleman, T. Nocera, J. Rodrigue, A. Silvis, and C. Whitman. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. All authors conceived the ideas and designed methodology; Robin Russell, Michael St. Germain, Chris Dobony, Mark Ford, Susan Loeb, and David Jachowski collected the data; Sara Bombaci and Robin Russell analyzed the data; Sara Bombaci and David Jachowski led the writing of the manuscript. All authors contributed critically to the drafts and gave final approval for publication.

Montana's wolf (Canis lupus) conservation and management plan is based on adaptive management principles and includes regulated public harvest as a population management tool. The need and opportunity to implement public harvest in 2008, 2009, and 2010 required Montana Fish, Wildlife and Parks (FWP) to develop a stepped down adaptive management framework specific to harvest. For 2008 and 2009, FWP set modest objectives: implement a harvest, maintain a recovered population, and begin the learning process to inform development of future hunting regulations and quotas. In 2010, FWP used a formal Structured Decision Making Process to more clearly define priorities and challenges of setting a wolf season, outline objectives of a successful season, and evaluate consequences and trade-offs between alternative management actions. For all years, FWP used a modeling process to simulate a wide range of harvest rates across three harvest units and to predict harvest effects on the minimum number of wolves, packs and breeding pairs. Model inputs were derived from minimum wolf numbers observed in the field. Modeling allowed consideration of a range of harvest quotas, predicted outcomes, and risk that harvest could drive the population below federally-required minimums. It also facilitated explicit consideration of how well a particular quota achieved objectives and how to adapt future regulations and quotas. Legal challenges to federal delisting restricted implementation of the first fair chase hunting season to 2009. Montana's wolf population is securely recovered, despite the dynamic political and legal environments. Regardless, FWP remains committed to a scientific, data-driven approach to adaptive management.