Limited Range

Green Sea Turtle (Chelonia mydas) Photo: Tim Laman/National Geographic
Green Sea Turtle (Chelonia mydas)
Photo: Tim Laman/National Geographic

The green sea turtle (Chelonia mydas) can be found around the world in tropical and warm temperate waters, and is ranked as endangered by the IUCN and CITES for a variety of reasons: pollution, habitat destruction, fishing practices, illegal poaching; the usual suspects. Because the turtles range between their nesting sites and feeding grounds, even if the nesting areas themselves are protected, the turtles are still in critical danger once they venture far and wide to forage.

Marine Protected Areas (MPAs) around the world, and are designated areas where human activities such as fishing are restricted. And while the negative economic impact on fishing or local activities has often been used as an argument against MPAs, the success of these areas in protecting not only sea turtles but a wide array of other marine life is gaining ever more evidence. The big breakthrough in finding this evidence has been the use of reliable satellite tracking technology, as well as the development of extensive underwater habitat maps.

In Florida, conservation efforts have found success in protecting both nesting areas and feeding areas – and a new study out shows that the turtles which use Dry Tortugas National Park off the southwestern tip of the Florida Keys also have more limited feeding ranges. They are using many of the surrounding areas of the Florida Keys Marine National Sanctuary rather than swimming farther afield.

Turtles have been around for over 220 million years. They are older than alligators or lizards, and outlived the dinosaurs. What I’m wondering is, did the Florida population of adult turtles alter their habitual foraging range to take advantage of the protected areas of the Florida Keys?

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Dry Tortugas National Park and the Florida Keys
More:
ScienceDaily article – Sea turtles benefiting from protected areas
ScienceDaily article – Marine turtle movements tracked