American alligators have long been recognized as a keystone species in the wetland ecology of south Florida. The burrowing activities of alligators deepen existing open water ponds and also create depressions, or “gator holes”, along pond margins and underneath tree roots.
Gator holes typically retain water during the dry season and thus maintain aquatic habitat for numerous aquatic species. They function as aquatic refugia on a local scale in the dry season for amphibians, reptiles, fishes, and aquatic macro-invertebrates.
Seven survey transects were delineated within the study area to characterize American alligator distribution across the landscape. These were located within the Picayune Strand Restoration Project area and served as restoration (hydrologically disturbed) transects. Three transects were chosen within adjacent conservation lands (Fakahatchee Strand Preserve State Park and Florida Panther National Wildlife Refuge) to serve as reference (less disturbed) transects.
Two biologists utilized a canoe with trolling motor along five of the transects while the remaining two required ground transport or walking.
Surveys started a half hour after sunset and could last until 3 a.m. the following morning. Hand-held spotlights were the primary means of locating alligators by their reflective red eye-shine.
Animals were approached with stealth to avoid submersion and size estimates were recorded. A biologist with crocodilian survey experience recorded measurements for consistency.
Measurements were recorded as total length on 0.25 m increments within a scale from 0.25 to 3.0 m. Any alligator observed at 0.25 m was denoted as a hatchling. Juveniles were recorded as between 0.5 -1.5 m and adults as greater than 1.5 m.
Methodologies for one transect differed from the other transects because night surveys for alligators in the remote interior of the Fakahatchee Strand would have proved logistically unfeasible and unsafe.
A total of 2,297 American alligators were observed during the month long survey period. Abundance values and mean length of alligators were considerably greater along reference transects.
1495 Smith Preserve Way Naples, Florida 34102
Monday - Sunday 9:30 am - 4:30 pm (ET)
239-262-0304 phone 239-262-0672 fax
©2017 Conservancy of Southwest Florida. All Rights Reserved