The goal of our work...

is to gain knowledge that will inform decision makers on the steps necessary to recover threatened and endangered species, while providing training to future scientists and policy makers through graduate education. Legally, recovery entails removal of a species protected by the Endangered Species Act from the list of endangered or threatened species. Ecologically, recovery requires that there is a high probability of persistence of a viable population for the foreseeable future. Our focus is on understanding the ecological factors that cause reductions in the distribution and abundance of a species. Our approach involves integration of methods across the range of a study species so that results are comparable in space (geography) and time (years). The education of graduate students forms the foundation of our program: graduate students lead the design, implementation, analysis, and reporting of our work.

Our program currently focuses on the ecology of the federally endangered golden-cheeked warbler (Dendroica chrysoparia) and black-capped vireo (Vireo atricapilla). The warbler is confined during breeding to juniper-oak woodlands of central Texas, while the breeding range of the vireo is largely confined to low scrubby deciduous vegetation in Texas and northern Mexico. For both species we are exploring broad-scale (landscape) factors that drive presence or absence of the species; more local (patch) scale factors that influence bird abundance; and micro-scale (foraging and nest site) factors that determine productivity and survival. Within the context of our overall research goals for these species, graduate students conduct specific studies that explore how various ecological factors influence the activity of the species and ultimately limit population sizes.