Wednesday, September 14, 2011

Hawksbill Sea Turtles: endangered species discovered in Pacific mangroves

Sea turtles, collectively, are some of the most endangered animals in the sea, due to loss of habitat, illegal poaching for the turtles and their eggs, and as accidental bycatch. The hawksbill sea turtle is no exception and, in fact, is listed by the World Conservation Union as critically endangered and CITES prohibits the capture and trade of hawksbill trutles and any products derived from them.

However, such proclamations of status and prohibitions have not yet prompted the hawksbill turtle populations to recover. Even in the best of natural circumstances, sea turtle eggs and young hatchlings face formidable challenges that thins the population so just the hardiest, smartest, and luckiest survive.

Found throughout all oceans, primarily in warmer climates, hawksbill sea turtles often live among the corals reefs in the Caribbean and Indo-Pacific. By 2007, the eastern Pacific population of hawksbills were considered effectively wiped out. However, recent tracking studies lead by Conservation International has shown that the eastern Pacific variety of hawksbill may have found another habitat to call its home: saltwater mangroves.

The study, recently published in Biology Letters, reports,
"New satellite tracking data on female hawksbills from several countries in the eastern Pacific revealed previously undocumented behaviour for adults of the species. In contrast to patterns of habitat use exhibited by their Caribbean and Indo-Pacific counterparts, eastern Pacific hawksbills generally occupied inshore estuaries, wherein they had strong associations with mangrove saltwater forests. The use of inshore habitats and affinities with mangrove saltwater forests presents a previously unknown life-history paradigm for adult hawksbill turtles and suggests a potentially unique evolutionary trajectory for the species."

It's not clear as to whether the hawksbill migrated from more open water environments to the mangroves - perhaps as a defense reaction to a declining habitat - or whether the eastern Pacific hawksbill had, by some evolutionary quirk eons ago, found the mangroves to be a suitable home along with coral reefs. But it does add one more reason for preserving mangrove ecosystems which are currently losing ground to coastal development and pollution.

Today, every species of sea turtle is threatened with extinction to one degree or another; as yet, none are in the clear. There are several organizations - Conservation International, PRETOMA, Turtle Island Restoration Network, and others - who are working to preserve and protect sea turtles and the environments within which they thrive.

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