Post-nesting migrations of Galápagos green turtles Chelonia mydas in relation to oceanographic conditions: integrating satellite telemetry with remotely sensed ocean data

Abstract

ESR Endangered Species Research Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsSpecials ESR 4:57-72 (2008) - DOI: https://doi.org/10.3354/esr00066 Post-nesting migrations of Galápagos green turtles Chelonia mydas in relation to oceanographic conditions: integrating satellite telemetry with remotely sensed ocean data Jeffrey A. Seminoff1,*, Patricia Zárate2, Michael Coyne3, David G. Foley4,5, Denise Parker1, Boyd N. Lyon6,†, Peter H. Dutton1 1NOAA-National Marine Fisheries Service, Southwest Fisheries Science Center, 8604 La Jolla Shores Dr., La Jolla, California 92037, USA 2Charles Darwin Research Station, Puerto Ayora, Santa Cruz, Galápagos Islands, Ecuador 3SEATURTLE.ORG, 1 Southampton Place, Durham, North Carolina 27705, USA 4Joint Institute for Marine and Atmospheric Research, University of Hawai’i at Manoa, 1000 Pope Road, Honolulu, Hawai’i 96822, USA 5NOAA Fisheries, Environmental Research Division, Southwest Fisheries Science Center, 1352 Lighthouse Avenue, Pacific Grove, California 93950-2097, USA 6Department of Biology, University of Central Florida, PO Box 162368, Orlando, Florida 32816, USA *Email: jeffrey.seminoff@noaa.gov. †Deceased. ABSTRACT: Post-nesting movements of 12 green turtles from the Galápagos Islands (Ecuador) were tracked with satellite telemetry during the 2003 and 2005 nesting seasons. To illuminate potential environmental influences on turtle movements we compared tracks with a variety of remotely sensed oceanographic variables including sea surface temperature (SST), SST front probability, surface height anomaly, surface current, and surface chlorophyll a concentration. Three distinct post-nesting migratory strategies were observed, including oceanic migration to Central America (Type A1 movements, n = 3), residency within the Galápagos (Type A2 movements, n = 2), and movement into oceanic waters southwest of the Galápagos (Type B movements, n = 7). Two turtles migrating to Central America reached neritic foraging areas in Nicaragua and Panama that were 1500 and 1542 km, respectively, from their nesting sites, and one resident turtle established a foraging home range 75 km from its final nesting site. Oceanic movements occurred in waters with a mean SST of 26.5°C and mean surface chlorophyll a concentration of 0.18 mg m–3, whereas neritic movements were in waters with a mean SST of 24.3°C and mean surface chlorophyll a concentration of 0.47 mg m–3. All turtles accessed SST frontal zones at a greater rate than their availability, and at least 2 turtles conducted movements in the oceanic zone that were indicative of foraging activity. This is the first report of migratory corridors for Galápagos green turtles, confirming prior flipper tagging data that show that the Galápagos is a source rookery for green turtles in coastal areas of Central America. The high proportion of green turtles departing the Galápagos (83%) indicates that marine fisheries bycatch and directed hunting on this stock outside the Galápagos may impact this population more than previously believed, and underscores the need for multi-national conservation efforts that combat these threats. KEY WORDS: Black turtle · Chelonia agassizii · Cheloniidae · Chlorophyll a · Eastern Tropical Pacific Ocean · Frontal zones · Migration · Sea surface temperature · Sea surface height anomaly Full text in pdf format Supplementary appendix PreviousNextCite this article as: Seminoff JA, Zárate P, Coyne M, Foley DG, Parker D, Lyon BN, Dutton PH (2008) Post-nesting migrations of Galápagos green turtles Chelonia mydas in relation to oceanographic conditions: integrating satellite telemetry with remotely sensed ocean data. Endang Species Res 4:57-72. https://doi.org/10.3354/esr00066Export citation Mail this link - Contents Mailing Lists - RSS Facebook - Tweet - linkedIn Cited by Published in ESR Vol. 4, No. 1-2. Online publication date: January 18, 2008 Print ISSN: 1863-5407; Online ISSN: 1613-4796 Copyright © 2008 Inter-Research.