Keywords
Chelonia mydas, foraging ecology, nutrient analysis, juvenile green turtle, feeding selectivity, electivity index
Abstract
For the endangered green turtle, Chelonia mydas, a fundamental component of recovery and conservation is an understanding of its foraging ecology. Foraging optimality models suggest animals will select resources of high quality over those of low quality. For green turtles, this behavior is important, as sufficient quantities of nutritionally adequate forage items are necessary for growth and reproduction. One intrinsic element in the understanding of green turtle foraging ecology is to identify and document the availability and quality of forage resources preferred by green turtles. The objectives of this study were: 1) determine whether juvenile green turtles showed a feeding preference by comparing prey items in the diet to the availability of those items in the habitat, 2) identify species for which there was selection or avoidance, 3) identify nutritional factors determining selection or avoidance of prey items, and 4) evaluate the nutritional content of the diet. This research was conducted by comparing lavage samples from juvenile green turtles to samples from benthic surveys within the habitat. To determine feeding preference, Ivlev's Electivity Index was used to compare ingested species of algae with those available in the habitat. Nutritional analysis of forage was conducted to identify possible nutrients relating to feeding preference. Juvenile green turtles selectively foraged on Chlorophyta and Rhodophyta. Results indicate that diet selection was based on nutritional content. Both the composite diet and the main diet item, Hypnea spp, had a higher gross energy value, were higher in protein, and lower in fiber than prey items that were avoided. Conservation of green turtles requires effective habitat management, which must be informed by an understanding and evaluation of the habitat. For juvenile green turtles, this study indicates that habitats dominated by Chlorophyta and Rhodophyta may be more important for the health of green turtle populations than habitats dominated by Phaeophyta.
Notes
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Graduation Date
2005
Semester
Spring
Advisor
Ehrhart, Llewellyn
Degree
Master of Science (M.S.)
College
College of Arts and Sciences
Department
Biology
Degree Program
Biology
Format
application/pdf
Identifier
CFE0000487
URL
http://purl.fcla.edu/fcla/etd/CFE0000487
Language
English
Release Date
January 2006
Length of Campus-only Access
None
Access Status
Masters Thesis (Open Access)
STARS Citation
Gilbert, Eliza, "Juvenile Green Turtle (chelonia Mydas) Foraging Ecology:feeding Selectivity And Forage Nutrient Analysis" (2005). Electronic Theses and Dissertations. 325.
https://stars.library.ucf.edu/etd/325