A team of researchers have tracked by satellite 135 leatherback turtles to determine that there are two spots in the Pacific where the creatures are in the greatest danger from longline fishing.
For a population of the giant turtles that nests in Costa Rica and Mexico the greatest danger is in a broad area off Perú known as the South Pacific Gyr, according to a report from Cornell University.
This group migrates along a corridor past the Galapagos Islands.
The gyr is an area where the ocean moves in a broad circle due to currents and winds.
One of the researchers is Stephen Morreale, a Cornell research associate. Also involved is James R. Spotila of Drexel University, who is known to Costa Ricans as the president of the Leatherback Trust.
Researchers also identified a second Pacific turtle population that nests in Indonesia and feeds off the California coast, according to a Cornell University summary.
Morreale and others entered the satellite data into a computer program along with other fishing data to predict the hot spots where turtles are snagged by commercial fishing boats, said the university.
“It’s a waste,” Morreale was quoted as saying. “This is not a case of people merely trying to feed their families. The fishing industry does not want to catch leatherbacks, and the turtles that are caught are just discarded.”
The maps created by the research reveal seasonal and geographic areas of greatest risk. The university said that the researchers hope to work with fisheries managers to avoid fishing when and where there is higher risk of catching turtles in the area.
The Proceedings of Royal Society B. published the study last month.
The university said that Morreale noted that much of the conservation emphasis has been on the turtle nesting spots, but only recently, through satellite transmitters, are researchers beginning to understand the turtles’ complex habits in the ocean, which will hopefully lead to better protection.
Leatherbacks (Dermochelys coriacea) are the largest sea turtles and the most massive reptile, reaching maximum weights of close to 2,000 pounds, the university noted.
John Roe, an assistant professor at the University of North Carolina, Pembroke, was the research paper’s lead author, along with Morreale and Frank Paladino at Indiana University-Purdue University at Fort Wayne.
Spotila founded the Leatherback Trust in 2001 with Paladino and has done research in Playa Grande on Costa Rica’s Pacific coast. That is a key turtle nesting spot.