The golden-cheeked warbler (Setophaga chysoparia; warbler hereafter) is an endangered migratory songbird that breeds exclusively in central Texas and winters in southern Mexico and Central America. On the breeding grounds, warbler habitat loss and degradation are the greatest threats to population persistence and most often occur via urbanization along the Interstate 35 corridor, where the U.S. Army’s Fort Hood Military Reservation, the U.S. Air Force’s Joint Base San Antonio-Camp Bullis, and the U.S. Army’s Camp Stanley are located. Similar threats exist on the wintering grounds. However, models of the warbler’s wintering range are limited and there is a lack of predictive models to forecast habitat conversion risks on the both the warbler’s breeding and non-breeding grounds, which could aid development of a more effective conservation prioritization strategy for this species. There is also a lack of data to examine migratory connectivity for warblers, which is of particular importance because spatial segregation of breeding populations during the non-breeding period could have major implications for warbler population dynamics. The research team will use change detection analyses and habitat forecasting to identify areas at highest risk of habitat conversion on the breeding grounds. In addition, researchers will use light-level geolocator technology (geolocator hereafter) to (1) test and refine the winter habitat model, (2) identify migratory and stopover locations, and (3) determine how populations of the focal species interact in non-breeding habitat. Finally, researchers will develop a data-driven decision support framework that helps inform off-post landscape-scale conservation planning for the warbler and manages risks during all stages of the species’ lifecycle, which is a necessary step toward warbler recovery and protecting on-post capability to implement the defense mission.

The research team will use remotely-sensed imagery obtained on the breeding and wintering grounds to quantify land cover change over time (1990–2015) and use historic land trends data (e.g., population density) to forecast locations with the greatest risk of habitat conversion at 25, 50, and 75 years into the future. Researchers will improve on previous winter habitat models using all locality data available from published, unpublished, and online sources. They will deploy 100 geolocators per year at study sites located across the warbler’s breeding range and use the retrieved data to test and refine the warbler wintering habitat model. After researchers have forecasted locations with the greatest risk of warbler habitat conversion on their breeding and wintering grounds, they will develop a data-driven decision support framework for the warbler based on the biological requirements of the species, conversion risk, proximity to military lands, migratory connectivity, and feasibility of conservation efforts given local economies, public participation, availability of technical assistance, and the spatial distribution of formally protected land to assist with warbler recovery and protecting on-post capability to implement the defense mission.

Identifying focus areas for multi-agency conservation efforts on landscapes that include Department of Defense (DoD) facilities is essential for maintaining populations of threatened and endangered species (T&E) and protecting on-post capability to implement the defense mission. Achieving this goal requires scientifically defensible biological data and a thorough understanding of the spatial, temporal, economic, and jurisdictional factors that drive broad-scale habitat change over time. Where migratory species are concerned, minimizing potential impacts to the military mission further depends on the ability to manage potential risks during all stages of the species’ lifecycle. In addition to providing information necessary for warbler management and recovery, this research will demonstrate a model for strategic conservation planning that addressees the full life cycle of migratory T&E species, helps mitigate restrictions to military training, increases program efficiencies can be updated as new information becomes available, and provides baseline data to support initiatives similar to Sentinel Landscapes and Working Lands for Wildlife.