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Nearctic Neotropical migratory songbirds incur the highest mortality during migration. En-route, songbirds rely on a network of stopover sites to rest, refuel, and/or seek refuge during poor weather. Conservation strategies prioritize protection of sites that best meet these needs. However, the specific function of a stopover site is expected to vary in relation to factors, such as geographic location, surrounding landscape, and weather. To identify sites with the highest conservation value for migratory songbirds, a conceptual framework was independently developed to classify sites into three functional categories based on their geographic and landscape features: fire escapes, convenience stores, and full-service hotels. The few attempts to empirically validate this framework have focused on temperate stopover sites. We evaluated the framework by testing the hypothesis that a site’s geographic and landscape characteristics can predict its function. We used capture and radio-tracking data at an island and mainland site in the Yucatan Peninsula, Mexico to quantify mean and variance in daily capture rate, body condition, stopover duration, and departure behavior during autumn, with a focus on four species: Swainson’s Thrush ( Catharus ustulatus ), Red-eyed Vireo ( Vireo olivaceus ), Gray Catbird ( Dumetella carolinensis ), and Prothonotary Warbler ( Protonotaria citrea ). Our results supported our predictions that the island functions as a fire escape, providing refuge for very high numbers of birds after encountering crosswinds or headwinds over the Gulf of Mexico, and the mainland forest site serves as a full-service hotel. The framework provides valuable insight for strategic conservation planning and management of stopover sites for songbirds. We suggest future studies evaluate the framework’s application to non-forest bird species. Additionally, we encourage collaborative efforts to consolidate and integrate tracking data, capture data from migration banding stations, and radar-based bird density estimates across a broad geography to test the framework’s ability to inform conservation planning across species’ full migratory range.

Abstract The conservation of migratory birds poses a fundamental challenge, their conservation requires coordinated action across the hemisphere, but those actions must be designed and implemented locally. To address this challenge, we describe a multilevel framework for linking broad‐scale, full annual cycle prioritizations to local conservation actions for migratory birds. We developed hemisphere‐scale spatial prioritizations for the full annual cycle of migratory birds that breed in six different ecosystems in North America. The full annual cycle prioritizations provide a hemispheric context within which regional priorities can be identified. Finer resolution, regional prioritizations can then inform local conservation actions more effectively. We describe the importance of local conservation practitioner contributions at each level of the process and provide two examples of regional spatial prioritizations that were developed to guide local action. The first example focused on coastal North and South Carolina, USA, and used information on marsh birds, shorebirds, ecological integrity, and co‐benefits for people to identify Cape Romain, South Carolina as a high‐priority site for conservation action. The second example in Colombia used information on migrant and resident birds to identify the Cauca Valley as a high‐priority site. The multilevel conceptual framework we describe is one pathway for identifying sites for implementation of local conservation actions that are guided by conservation priorities for migratory birds across their full annual cycle.

Abstract Using acoustics to survey for bats has increased as the need for data on increasingly rare species has also increased. We set out to better understand the difference between mist netting and acoustic detection probabilities between these two methods for the little brown bat (Myotis lucifugus), a species highly impacted by white‐nose syndrome and currently considered for federal listing in the United States. We also analyzed occupancy relationships with local and landcover variables. We surveyed 15 sites using mist netting paired with an acoustic recorder for multiple nights to estimate detection probability of this species. We also deployed acoustic recorders at another 73 sites. We found that detection rates for mist netting were very low but increased with day of year and decreased from proximity to water. Acoustic surveys had higher detection rates, but there was an approximately 30% likelihood of false‐positive detections. At the mean distance to water and day of year, acoustic surveys had a detection rate 55 times higher than mist netting. There were not significant factors influencing occupancy of little brown bats, only a slight positive relationship between forested largest patch, landscape patch richness and forest basal area. Given the declines in little brown bat populations since white‐nose syndrome, it is even more critical that we consider the very low detection rate of mist netting compared to acoustic surveys.