Defense Date

8-11-2022

Document Type

Thesis

Degree Type

Master of Science

Degree Name

Marine Science

First Advisor

Derek Burkholder

Second Advisor

David Kerstetter

Keywords

egg chamber depth, hatching success, emergence success, clutch size, nest relocation, loggerhead sea turtle, Florida, embryonic development

Abstract

All seven extant species of sea turtle are either threatened or endangered due to a multitude of anthropogenic and environmental factors. There has been strong emphasis on reversing this trend through various conservation efforts at multiple life stages, yet, if hatchlings never develop within the nest or are unable to escape the egg chamber, then these efforts are futile. Understanding how they develop, the factors impacting this development and their ability to emerge from the egg chamber are essential for sea turtle conservation. Important factors that may impact hatching success (HS) and emergence success (ES) are egg chamber depth (ECD) and clutch size. The ECD contributes to the cumulative effects of most parameters affecting embryonic development and emergence from the egg chamber while clutch size contributes to the amount of metabolic heating within the nest. If ECD and clutch size significantly impact HS and ES, then identifying an optimal egg chamber depth (OECD) based on clutch size may be useful in maximizing HS and ES. This study examined this relationship through model development for in situ and relocated nests in Broward County, FL. The ECD and clutch size influenced HS and ES, allowing the OECD that maximizes HS and ES to be determined for all nests as well as specified clutch size ranges. Nest location impact to OECD, HS, and ES was examined but no strong trends were observed. Results from this study can be applied to nest relocation methodologies to maximize the hatchling output of any given relocated nest.

Download
Share Feedback

Share

COinS