Protected 'Swimways' Urged For Endangered Leatherback Sea Turtle

ScienceDaily 20 Oct 08;

The International Union for the Conservation of Nature's (IUCN) World Conservation Congress this week adopted a resolution urging nations to protect the leatherback sea turtle and sharks from the world's industrial fisheries by identifying and creating marine protected areas along the Pacific leatherback's migratory routes.

More than 8,000 scientists, government officials and environmental organizations from over 250 nations overwhelmingly supported the resolution, which includes the "Cocos Ridge Marine Wildlife Corridor," designed to shield the critically endangered Pacific leatherback and the hammerhead shark from longline and gillnet fisheries. Recent satellite tracking data from Stanford University researchers shows that after nesting on the beaches in Playa Grande, Costa Rica, Pacific leatherbacks swim toward the Galapagos Islands.

Randall Arauz, President of Costa Rican-based PRETOMA that sponsored the resolution explained, "Our plan allows one of the largest reptiles on Earth to continue its 100-million-year-old existence by opening and closing portions of the migration corridor to fishing as turtles enter and exit the area." He added, "We believe this corridor is also used by other endangered species, such as hammerhead sharks and would benefit many other threatened marine species."

The resolution employs scientific recommendations based upon fieldwork and analyses by Stanford researcher, George Shillinger and an international team of co-authors who believe their work may make "adaptive" closures a realistic conservation approach, "These models will consider areas of highest risk/interaction with fisheries and provide governments and fisheries with the opportunity to protect leatherbacks as they move in real-time."

In the recent study, Persistent Leatherback Turtle Migrations Present Opportunities for Conservation, Shillinger used satellite tracking and remote sensing to describe the effects of oceanography, such as ocean currents, phytoplankton distribution and sea-floor topography, on Pacific leatherbacks' distribution and movement; and then developed a model that could predict the presence or absence of the sea turtles. His work is part of the Census of Marine Life's (CoML) Tagging of Pacific Pelagics (TOPP) initiative, a multidisciplinary, international research program utilizing electronic tags to track the migrations of a variety of open ocean animals. Shillinger adds, "Now it's time to turn the high-tech science into political will and conservation action for critically endangered leatherbacks."

The last members of an ancient lineage that has outlived the dinosaurs, leatherback sea turtles are ocean giants that grow to the size of small automobiles, dive more than half a mile deep, and migrate across the entire Ocean basins to feed in the jellyfish-rich waters off the west coast of North and South AmericaLeatherbacks swim over 6,000 miles within a single year - the largest geographic range of any living marine reptile, and one of the longest known migrations for any marine species in the world.

"Leatherback sea turtles survived the asteroid that killed off the dinosaurs, but they are unlikely to survive our unsustainable appetite for swordfish and tuna," said Todd Steiner, Executive Director of the U.S.-based Turtle Island Restoration Network and a member of the IUCN Marine Turtle Specialist Group. "If leatherbacks are to survive the coming decades, we must convert talk to action; otherwise we will lose one of the most ancient creatures on the planet, in the next ten to thirty years."

Leatherback sea turtles in the Pacific Ocean have declined by more than 90% over the past three decades as a result of drowning in industrial longline and gillnet fisheries targeting swordfish, sharks, and tunas. Egg harvesting, marine plastic debris and loss of nesting beaches due to global warming-induced sea level rise also threaten the leatherback. If current trends continue, Pacific leatherbacks are predicted to go extinct within the next few decades.