9707622 Fitzpatrick This proposal will support the continuation of a long-term study of the ecology, demography, and conservation biology of the Florida Scrub Jay, a species listed as federally threatened. The study of a color-marked population at Archbold Biological Station in south-central Florida has proceeded uninterrupted since 1969. The study has produced a important discoveries in animal behavior, sociobiology, demography, life history theory, evolution, and ecology, and has spawned widespread attention to the conservation biology of an ancient ecosystem unique to Florida. In addition to labor-intensive demographic monitoring of about 60 Florida Scrub Jay territories, current field work emphasizes 1) distribution of arthropod, vertebrate, and plant food resources through space and time, 2) long-term effects of natural fire cycles and post-fire succession on jay demography, resource availability, and oak reproductive effort; 3) the role of episodic disease in population regulation; and 4) source-sink dynamics in natural as compared with human-modified habitats. Recent completion of a major program of GIS data-preparation, and a series of large-scale field experiments employing prescribed burning, have opened new opportunities to understand the long-term effects of environmental variation and natural perturbation within the Florida scrub ecosystem. Overall, this project uill continue the extensive regime of question-driven ecological monitoring which represents the foundation of this long-term study.