Nearshore Habitat Usage of Juvenile Kemp's Ridleys in the Northern Gulf of Mexico

Understanding the causes of sea turtle strandings is key for minimizing the occurrence of such events and their impacts on sea turtle population status. Knowledge about the origins of stranded turtles, their susceptibility to human impacts such as fisheries bycatch, and their post-interaction behaviors are fundamental components that can help guide the most appropriate management strategies. In the northeast Gulf of Mexico there has been a recent spike in strandings of juvenile Kemp¿s ridley turtle since 2010, signaling the need for focused research to determine the causes for this apparent increase. To better understand these strandings we conducted an initial study to learn more about Kemp¿s ridley turtles using the Mississippi Sound and nearby nearshore waters, we applied satellite transmitters to and collected tissue samples for stable isotope analysis from three juveniles (38.1cm, 49.8cm, and 53.1cm SCL) caught incidentally during trawl gear evaluation research which began in early May 2014.

The intention of the project is to learn how juvenile Kemp's ridley turtles in the northeastern Gulf of Mexico are using the nearshore habitats by identifying habitat usage and movements, paying particular attention to areas where turtles congregate. We will identify a prey base through foraging ecology sampling collecting tissue from putative prey species and will analyze stable carbon and nitrogen ratios in skin and or blood samples.

This project is being worked on collaboratively by the individuals/agencies listed below.

Lisa Belskis- NOAA NMFS SEFSC, Miami, Florida

Wendy Teas- NOAA NMFS SEFSC, Miami, Florida

Chris Sasso- NOAA NMFS SEFSC, Miami, Florida

Jeffrey Seminoff- NOAA NMFS SWFSC, La Jolla, California

Brian Stacy- NOAA NMFS OPR, Gainesville, Florida

Melissa Cook- NOAA NMFS SEFSC, Pascagoula, Mississippi

Dominy Hataway- NOAA NMFS SEFSC, Pascagoula, Mississippi

Jeff Gearhart- NOAA NMFS SEFSC, Pascagoula, Mississippi

Paul Richards- NOAA NMFS SEFSC, Miami, Florida

Lee Saxon- Riverside Technology Inc.

A cruise report entitled ¿2014 Comparative Towing and Gear Evaluation Cruise, R/V Caretta, April 30-May 09¿ produced by Lee Saxon summarizing the trip.

Carapace measurements are taken in centimeters to the nearest tenth of a centimeter.

As of April 2, 2015 three of the anticipated ten Kemp's ridley turtles have been caught, sampled and tagged.

CLSL-Carapace length straight length is measured from the nucal notch to the longest tip of the carapace taken with calipers in centimeters.

CLSL Min-Carapace length straight length minimum is measured from the nucal notch to the notch between the superpygal scutes at the tip of the carapace taken with calipers in centimeters.

CWSL-Carapace width straight length is measured at the widest point of the carapace taken with calipers in centimeters.

CLOC- Carapace length over curve measured from the nucal notch to the longest tip of the carapace taken with a flexible tape measure in centimeters.

CLOC Min-Carapace length over curve minimum is measured from the nucal notch to the notch between the superpygal scutes at the tip of the carapace taken with a flexible tape measure in centimeters.

CWSL-Carapace width over curve is measured at the widest point of the carapace taken with a flexible tape measure in centimeters. Note- this location may be different then the CLOC depending on the shape of the individual turtle.