Behavior, Ecology, and Conservation of Sea Turtles in the North Atlantic Ocean

• Main Author: McClellan, Catherine Marie
• Other Authors: Read, Andrew M
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: 2009
• Subjects: Biology; Ecology; Environmental Sciences; animal movement; Bycatch; marine vertebrates; satellite telemetry; sea turtle; stable isotopes; North Atlantic
• Online Access: https://hdl.handle.net/10161/1128

Sea turtles have experienced dramatic population declines during the last century as a consequence of direct harvest, by-catch in fisheries, and habitat loss. Despite almost 50 years of partial international protection, several populations of sea turtles are still at imminent risk of extinction. Our knowledge of their complex life histories is still far from complete; these knowledge gaps hinder our ability to provide scientific advice regarding their conservation and management. It is the very complexity of their life histories, which allows them to exploit widely separated habitats during development, often over the course of decades, which makes them inherently difficult to study. I used satellite telemetry (n=60) to investigate the movements and habitat use patterns of juvenile loggerhead ( Caretta caretta ), green ( Chelonia mydas ), and Kemp's ridley ( Lepidochelys kempii ) sea turtles on their summer feeding grounds in North Carolina estuaries. These turtles migrate into and out of the estuarine waters each spring and autumn, encountering a gauntlet of fishing gear on each journey. The by-catch of sea turtles is an important conservation issue in North Carolina, and throughout the world's oceans. I evaluated conservation measures established to reduce the by-catch of sea turtles in Pamlico Sound's autumnal large-mesh gill net fishery for southern flounder ( Paralichthys lethostigma ), using a spatially explicit predator/prey model. My findings indicated that species-specific habitat preferences contributed to a turtles' risk of encountering fishing gear and that areas of high by-catch are predictable from patterns of overlap between sea turtle habitat use and flounder fishing effort. I then examined how the behavior of green turtles affected their vulnerability to incidental capture in estuarine commercial fisheries. Individual green turtles interact with multiple gears per season as a result of strong site fidelity to habitats also preferred by fishers. Telemetry also allowed me to examine individual ...