Featured Research

from universities, journals, and other organizations

Critically endangered leatherback turtles tracked to reveal danger zones from industrial fishing

Date:
February 3, 2014
Source:
Cornell University
Summary:
One of the biggest threats to critically endangered leatherback turtles is bycatch from industrial fishing in the open oceans. Now, a team of researchers has satellite-tracked 135 leatherbacks with transmitters to determine the turtles’ patterns of movement in the Pacific Ocean. Combined with fisheries data, the researchers entered the information into a computer model to predict bycatch hotspots in the Pacific.

A green turtle injured by a longline hook off the west coast of Costa Rica.
Credit: Samuel Friederichs

One of the biggest threats to critically endangered leatherback turtles is bycatch from industrial fishing in the open oceans.

Now, a team of researchers has satellite-tracked 135 leatherbacks with transmitters to determine the turtles' patterns of movement in the Pacific Ocean. Combined with fisheries data, the researchers entered the information into a computer model to predict bycatch hotspots in the Pacific.

With this information, researchers and authorities hope to work with fisheries managers to avoid fishing when and where there is higher risk of also catching turtles in the area. Though the ocean is vast and the turtles' movements are dynamic and unpredictable, the small chance of an individual leatherback getting hooked or caught in fishing lines is multiplied by 760 million in the Pacific Ocean alone, said Stephen Morreale, referring to the number of longline hooks set annually in the Pacific. Morreale is a Cornell University senior research associate and adjunct associate professor in the Department of Natural Resources. He is a co-author of the study published online Jan. 7 in the Proceedings of Royal Society B.

"It's a waste," Morreale said. "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."

In the Pacific, the researchers identified two genetically distinct populations, one western Pacific population that nests in Indonesia and feeds off the California coast, and another eastern Pacific population that nests in Costa Rica and Mexico and migrates along a corridor past the Galapagos Islands to a broad pelagic zone known as the South Pacific Gyre.

The maps reveal seasonal and geographic areas of greatest risk. For the western Pacific nesting populations, areas of highest risk included water around the Indonesian Islands near primary nesting beaches, and for the eastern Pacific populations, areas of greatest risk were in the South Pacific Gyre.

Leatherbacks are the largest sea turtles and the most massive reptile, reaching maximum weights of close to 2,000 pounds. The leathery-shelled turtles, which feed on jellyfish, use their flippers like wings to swim vast distances at surprising speeds; they also dive to depths of 1,200 meters, shuttling to and from the surface to breathe.

Once they hatch, males spend their entire lifetimes in the water. They take up to 20 years to reach maturity. As adults, females return throughout their lifetimes to the same nesting beach to lay clutches of 80 to 100 eggs in the sand, which they may repeat every two weeks over the course of a nesting season. Once they have laid all their eggs, they may not return for three to five years.

Because of the many risks over decades that leatherbacks face before they reach maturity, "an adult's [ecological] value is huge," said Morreale. Also, since so little has been known about their movements once they enter the ocean, conservationists have historically focused on protecting beach areas where they can be monitored and protected.

But "their protection at sea is extremely important," and only recently, through satellite transmitters, are researchers beginning to understand the turtles' complex habits in the ocean, which will hopefully lead to better protection, said Morreale.

Next steps for this research include acquiring more Pacificwide data for interactions between fisheries and turtles, as well as data for the Atlantic Ocean, Morreale added. John Roe, an assistant professor at the University of North Carolina, Pembroke, was the paper's lead author, along with Morreale and Frank Paladino at Indiana University-Purdue University at Fort Wayne, while Drexel University professor James Spotila assembled the research team.

Funding was provided mainly by the Lenfest Oceans Program.


Story Source:

The above story is based on materials provided by Cornell University. Note: Materials may be edited for content and length.


Journal Reference:

  1. J. H. Roe, S. J. Morreale, F. V. Paladino, G. L. Shillinger, S. R. Benson, S. A. Eckert, H. Bailey, P. S. Tomillo, S. J. Bograd, T. Eguchi, P. H. Dutton, J. A. Seminoff, B. A. Block, J. R. Spotila. Predicting bycatch hotspots for endangered leatherback turtles on longlines in the Pacific Ocean. Proceedings of the Royal Society B: Biological Sciences, 2014; 281 (1777): 20132559 DOI: 10.1098/rspb.2013.2559

Cite This Page:

Cornell University. "Critically endangered leatherback turtles tracked to reveal danger zones from industrial fishing." ScienceDaily. ScienceDaily, 3 February 2014. <www.sciencedaily.com/releases/2014/02/140203101001.htm>.
Cornell University. (2014, February 3). Critically endangered leatherback turtles tracked to reveal danger zones from industrial fishing. ScienceDaily. Retrieved July 25, 2014 from www.sciencedaily.com/releases/2014/02/140203101001.htm
Cornell University. "Critically endangered leatherback turtles tracked to reveal danger zones from industrial fishing." ScienceDaily. www.sciencedaily.com/releases/2014/02/140203101001.htm (accessed July 25, 2014).

Share This




More Earth & Climate News

Friday, July 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Goma Cheese Brings Whiff of New Hope to DRC

Goma Cheese Brings Whiff of New Hope to DRC

Reuters - Business Video Online (July 24, 2014) — The eastern region of the Democratic Republic of Congo, mainly known for conflict and instability, is an unlikely place for the production of fine cheese. But a farm in the village of Masisi, in North Kivu is slowly transforming perceptions of the area. Known simply as Goma cheese, the Congolese version of Dutch gouda has gained popularity through out the region. Ciara Sutton reports. Video provided by Reuters
Powered by NewsLook.com
Bill Gates: Health, Agriculture Key to Africa's Development

Bill Gates: Health, Agriculture Key to Africa's Development

AFP (July 24, 2014) — Health and agriculture development are key if African countries are to overcome poverty and grow, US software billionaire Bill Gates said Thursday, as he received an honourary degree in Ethiopia. Duration: 00:36 Video provided by AFP
Powered by NewsLook.com
Higgins Breaks Record at Mt. Washington

Higgins Breaks Record at Mt. Washington

Driving Sports (July 24, 2014) — Subaru Rally Team USA drivers David Higgins and Travis Pastrana face off against a global contingent of racers at the annual Mt. Washington Hillclimb in New Hampshire. Includes exclusive in-car footage from Higgins' record attempt. Video provided by Driving Sports
Powered by NewsLook.com
Storm Kills Three, Injures 20 at Virginia Campground

Storm Kills Three, Injures 20 at Virginia Campground

Reuters - US Online Video (July 24, 2014) — A likely tornado tears through an eastern Virginia campground, killing three and injuring at least 20. Linda So reports. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

    Health News

      Environment News

        Technology News



          Save/Print:
          Share:  

          Free Subscriptions


          Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

          Get Social & Mobile


          Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

          Have Feedback?


          Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
          Mobile iPhone Android Web
          Follow Facebook Twitter Google+
          Subscribe RSS Feeds Email Newsletters
          Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins