Where do Black Sea Turtles feed? Using Stable Isotopes and Satellite Tracking
Latest update May 31, 2019 Started on December 10, 2018The largest Black Sea Turtle nesting population arrives at Colola, Mexico. Where will they migrate after nesting? We will use stable isotopes and satellite tracking to know what they´re eating, and identify the important feeding areas!
We are very excited to say that we recieved our Trident under water drone, donated by the SEE initiative the SOFAR technologies!!! We are testing the drone and getting the hang of using it! This will help us in a great way to study sea turtle in-water behavior.
The next step is testing the drone in the field in an olive ridley feeding area off-coast of Sinaloa in the Gulf of California. We will keep you updated on the awesome videos we record. Thank you, on behalf of the Wildlife Conservation Team at the CIIDIR-Sinaloa in Guasave, Sinaloa, Mexico.
Turtlers invade Colola in search for female nesting black turtles. We finally tagged 10 nesting turtles with satellite transmitters and reached our goal sample for this season! We use a mix of epoxy adhesives and glass fiber cloth to place the tags on the turtles carapace. After this dries, the turtles are ready to head back to the ocean and lead the way to their feeding grounds in the eastern Pacific!
After weeks of preparation and years of planning, we have started tagging turtles on Colola beach. Looking for a turtle that is ready to carry a satellite tag has been a great challenge. We are searching for nesting females that have a "dry" carapace (green turtles tend to have a very oily carapace, which makes tag retention difficult), that has finished laying eggs, and we have to make sure this is the last clutch the turtle will lay this season. To do this, the candidates’ oviduct is revised for follicles. According to one of our collaborators, Dr. Carlos Delgado, this year is the first ever for him to see so many turtles nesting so near to the end of the season. This is very good, in theory for us, because this means that we reach our goal samples faster and easier. But the surprising aspect of this field-trip is that all of the turtles which have had an ultrasound exam are apparently on their first laying of the season. Dr. Catherine Hart, who is also collaborating in this project, thinks that the population may be divided into two or more cohorts and this may be likely the reason these particular "batch" of turtles are not at the "end of the season".
The green sea turtle (Chelonia mydas), known in the Eastern Pacific region as a black turtle, has been proposed as an independent species or subspecies by several authors due to its morphological characteristics. It is considered a very important genetic heritage for the Chelonia mydas species for which it is considered a distinct population segment (DPS) because of its evolutionary potential. The present work aims to identify the spatial ecology of the black sea turtles that nest on the beach of Colola Michoacán, Mexico, with the use of stable isotope analysis and satellite telemetry. The data provided by this study can finally provide information on the conservation at the marine landscape level, characterizing the home environment of the species, through physical, chemical and biological variables; contributing to marine spatial planning activities to ensure the sustainable persistence of both the C. mydas species in its range in the Eastern Pacific and the conservation of the habitat it occupies.
