Kemp’s ridley turtles (Lepidochelys kempii) are the smallest and the most endangered of all the sea turtle species. Although their native habitat is restricted to the Gulf of Mexico and east U.S. coast, occurrences of juvenile Kemp’s ridley turtles in the north-western European coasts have also been documented in the past, particularly in winter months. Since turtles are ectotherms, hypothermic conditions during winter induces sluggish behaviour in them and they lose their ability to actively swim, a condition termed as ‘cold stunning’. For Kemp’s ridley turtles, cold stunning is known to occur below ocean temperatures of 10-12°C, causing them to float at the surface ocean. Knowledge on the dispersion of these cold stunned turtles can help improve their rehabilitation success rate in the Netherlands. In this study, we perform Lagrangian modelling of surface ocean transport of juvenile turtles that were found stranded alive on the Dutch coast in cold stunned state over the last 15 years. We find that these turtles enter through the English Channel and only first encounter cold conditions from a few days to a months’ time before stranding.

Primary Presenter: Darshika Manral, Utrecht University (d.manral@uu.nl)

Authors:

Darshika Manral, Institute for Marine and Atmospheric Research, Utrecht University, Utrecht, Netherlands  (d.manral@uu.nl)

Ilse Bos, Department of Biology, Utrecht University, Utrecht, Netherlands  (ilse.bos@student.uva.nl)

Mark de Boer, Curator Fishes, Reptiles, Amphibians and Invertebrates, Rotterdam Zoo, Rotterdam, Netherlands  (m.de.boer@diergaardeblijdorp.nl)

Erik van Sebille, Institute for Marine and Atmospheric Research, Utrecht University, Utrecht, Netherlands  (e.vansebille@uu.nl)