Characterizing juvenile green turtles, (Chelonia mydas), from three east central Florida developmental habitats

Keywords

Green turtle -- Habitat -- Florida; Sea turtles -- Florida

Abstract

The life history of marine turtles remains poorly understood even after more than five decades of study. Adults and hatchlings are commonly studied on the nesting beach where they are readily accessible. Much less is understood about the juvenile years because of the difficulty both in locating developmental habitats and studying marine turtles in the marine environment. Juvenile green turtles (Chelonia mydas) have been studied continuously in three distinctly different developmental habitats in east central Florida. The first one is in the Indian River Lagoon, a shallow, poorly flushed estuary. The second is the nearshore Atlantic reef system, characterized by worm rock formed by Sabellariid polychaetes. The third is the Trident Submarine Turning Basin at Port Canaveral, Florida, is a manmade enclosure lined with algae-covered granite boulders. The UCF Marine Turtle Research group has worked in these areas since 1982, 1989 and 1993 respectively. To characterize these three aggregations in terms of morphometrics, sex ratio, fibropapillomatosis and genetics, 100 immature turtles from each site were captured, tagged, a blood sample collected, measured, examined, photographed and released. The size range of all 300 turtles was 24.1 to 73.0 cm SCL, with means of30.9 cm, 39.6 cm and 40.1 cm. Radioimmunoassay indicates that all three aggregations are significantly female biased at 68%, 79% and 80%. While the fibropapillomatosis prevalence is as high as 71.6% at one site, it remains at low frequency in another, and no trace of the disease has been found in the third. Analysis of mitochondrial DNA reveals that, in terms of numbers of haplotypes found, these three aggregations are the most

genetically diverse studied to date. Mixed stock analysis suggests that the contributions to these three aggregations from previously surveyed nesting populations were 53-94% from Florida and Mexico, 3-40% from Costa Rica, 1-4% from Aves Island and Surinam, 1-3% from Ascension Island and Guinea Bissau and 1-2% from Cyprus. Locally, the greatest threats to immature animals seem to be boat collisions and monofilament entanglement. Tag returns indicate that turtles leaving the east central Florida coast are captured in local fisheries in Belize, Cuba, the Dominican Republic and Nicaragua.

Notes

This item is only available in print in the UCF Libraries. If this is your thesis or dissertation, you can help us make it available online for use by researchers around the world by STARS for more information.

Graduation Date

2003

Advisor

Ehrhart, Llewellyn M.

Degree

Master of Science (M.S.)

College

College of Arts and Sciences

Department

Biology

Format

PDF

Pages

113 p.

Language

English

Length of Campus-only Access

None

Access Status

Masters Thesis (Open Access)

Identifier

DP0029090

Subjects

Arts and Sciences -- Dissertations, Academic; Dissertations, Academic -- Arts and Sciences

This document is currently not available here.

Share

COinS