|Session VI: Bird & Animal Studies
||Abstract #: 97602
WATER BIRD USAGE OF FLORIDA BAY
Joan Browder, Oron Bass, Jennifer Gebelein, and Haolon Huang
NOAA/National Marine Fisheries Service, Miami, & NPS/Everglades National Park, Walt Dineen Homestead
An aerial census of Florida Bay conducted from an HH65 Dolphin helicopter (courtesy U.S. Coast Guard, Miami Air Station) provides the first comprehensive multi-species, baywide view of wading bird abundance, spatial distribution, and habitat use. More than two complete years' of monthly observations reveal seasonal patterns.
Objectives are to (1) determine usage of various types of bay habitat, (2) determine overall abundances, (3) compare present to past abundances for a few species that have been counted previously, and (4) compare abundances and seasonal usage of the bay to that in mangrove and freshwater areas of Everglades National Park. During the first 9 mo, we flew regularly spaced north-south transects and diverted from the flight path to circle islands within one-half mile distance. Beginning month 10, we adopted a more efficient strategy that focused on islands and nearly exposed banks. White Ibis were the most abundant wading bird species the first winter, followed by Great and Snowy Egrets. The Great White Heron was the wader that most fully used the Bay. It was consistently the most widely distributed species across Florida Bay in all months. The Great Blue Heron was less numerous than the Great White Heron, more seasonal in its occurrence, and more restricted in its distribution (mainly the western and southwestern bay). During the winter, Great and Snowy Egrets were more numerous than Great White Herons. The spatial distribution of Great Egrets was similar to that of Great White Herons. One surprise was the large number of small wading bird species using the bay. Little Blue Herons, Snowy Egrets, and Tri-colored Herons extended deeply into the bay, not just along the northern fringe.