We haven’t seen our nesting turtles now for a few months, but for one special turtle named Enid Fern, we know exactly where she is, every single day!
People often ask us about the tagging we do with our turtles and if we are able to use those tags to see where the turtles are going. Normally, we use a rear flipper tag, which is a small metal tag that has a unique number on it. But the only way to track a flipper-tagged turtle is through observations on other beaches (very low chance!). Satellite tags are different. They are equipped with GPS locators and send their data to orbiting satellites when the turtle surfaces. We can then download the information and analyze it to figure out the fairly exact location of the turtle. This amazing technology has been used for hundreds of species to help us learn more about habitat use, migration patterns, and foraging grounds.
Enid Fern was a new turtle for us this year. She first nested on 24 April, and was named by team member Amy for her grandmother. She got her flipper tag that night (flipper tag SPP366), and then we saw Enid Fern three more times. She returned on 3 May for a nest and then on 13 May, she came back but didn’t nest (she’s a bit of fussy turtle when choosing a nesting site). But she was back the next night and nested successfully. That was the last we saw her on St. Croix. But on 8 June, I got an excited text from our friend Luis Crespo, leader of the community group ATMAR (Amigos de las Tortugas Marinas) in Maunabo, Puerto Rico: “SPP366 tried to nest at my beach, is she yours?” She was ours, and it was Enid Fern! She didn’t nest that night but returned to Maunabo on 9 June and did nest.
Now it gets interesting here because our colleagues Kara Dodge and Connie Merigo from the New England Aquarium (Anderson Cabot Center for Ocean Life) happened to be visiting Maunabo to deploy a couple of satellite tags on nesting leatherbacks in collaboration with ATMAR and the Puerto Rico Department of Natural and Environmental Resources. Enid Fern was in just the right place at the right time, and she got a satellite tag! Thanks to both organizations for sharing information and tracks with us! From that day until now, Enid Fern has been tracked as she migrated away from the nesting beaches and headed north to foraging grounds. The migration pathways and beach use by leatherbacks is an important management question in the Atlantic.
St. Croix and Puerto Rico share turtles sometimes, within and between seasons. From Sandy Point National Wildlife Refuge on St. Croix to the nearest leatherback beach (Maunabo, PR), it’s about 68 miles (~110 km). This distance is no problem for a leatherback to travel between nests (they spend 9-10 days at sea between nesting events). The reasons why the turtles choose a different beach is still a mystery. But the question of leatherback nesting distribution is an important one. Recently, leatherbacks have been declining in the Northern Caribbean. Next year we will begin a new satellite tagging program to understand just how leatherbacks are using all beaches in the region.
If you’d like to help us with our satellite tagging program collaborative in 2019, please consider a donation to one of our organizations (all are non-profit 501(c)(3))!
Thank you so much!