Seasonal movements of immature Kemp's ridley sea turtles (Lepidochelys kempii) in the northern gulf of Mexico

Abstract

ABSTRACT1. Seasonal movements and core habitat areas of immature Kemp's ridley sea turtles (Lepidochelys kempii) in the northern Gulf of Mexico were tracked via satellite telemetry. Tagged turtles were incidentally captured by recreational fishermen and rehabilitated at the Institute for Marine Mammal Studies in Gulfport, Mississippi.2. The average size of the core habitat areas (50% KDE (kernel density estimation)) was 1660.2 km 2 ± 3438.2 SD. Turtles displayed strong intra-and inter-annual site fidelity to the Mississippi Sound during the spring, summer, and autumn months. During the winter months, most turtles, probably influenced by water temperatures, migrated to nearshore waters of Louisiana on either side of the Mississippi River Delta. However, other migration strategies were also observed. 3. Overall, these data indicate that the Mississippi Sound is an important developmental habitat for this critically endangered species. In addition, their wintering grounds in Louisiana are utilized by adult Kemp's ridleys and other sea turtle species as foraging grounds and migratory corridors. The high use of these areas by sea turtle populations increases the potential for negative impacts from anthropogenic disturbances (e.g. shrimp trawling, oil production, hypoxia) that occur there.

Regional Variation in Kemp’s Ridley Sea Turtle Diet Composition and Its Potential Relationship With Somatic Growth

“…Therefore, in order for stranding to occur before carcasses dissociated due to decomposition, drift times and distances would have needed to be low (∼2-5 days, 15-30 km; Nero et al, 2013;Santos et al, 2018). Second, Kemp's ridleys display relatively high intra-and inter-annual site fidelity to nearshore, shallow (<50 m depth) foraging areas (generally <1,000 km 2 ) that are well constrained spatially within our defined geographic regions (Renaud and Williams, 2005;Schmid and Witzell, 2006;Shaver and Rubio, 2008;Seney and Landry, 2011;Coleman et al, 2017). Therefore, turtles that stranded within each geographic area are likely to have been foraging within their stranding location-assigned geographic area prior to death.…”

Variability in age and size at maturation, reproductive longevity, and long-term growth dynamics for Kemp's ridley sea turtles in the Gulf of Mexico

“…Previous studies recognized that sufficient habitat and forage would be required to accommodate this influx of juveniles [54] and indicated that carrying capacity for the population might be reached at smaller sizes than in the past and that an abrupt “crash” might occur [10, 11]. Both juvenile and adult Kemp’s ridleys exhibit site fidelity to GOM foraging areas [54–60], with juveniles preferring shallower-water habitat [55, 57, 61, 62]. Furthermore, studies have reported that Kemp’s ridleys may specialize in their diet preferences, focusing on swimming crabs (in particular the blue crab, Callinectes sapidus ), with additional consumption of various walking crab species [58, 63, 64].…”

Contribution of Remote Sensing Technologies to a Holistic Coastal and Marine Environmental Management Framework: A Review

“…• Turtles Satellite telemetry has been used to track the movement of turtles and changes. Coleman et al, 2017 [233] used a UUV attached to the back of sea turtles (called Platform Terminal Transmitter PPT) that is tracked with earth-orbiting satellite to follow the movement of turtles. The collected data showed changes that happened in the Mississippi-Gulf region.…”