UNC Pembroke researcher races to save the sea turtle

CorrespondentApril 13, 2014 

  • Meet a scientist

    When he was a child, UNC Pembroke biology professor John Roe, 38, did something he would definitely not condone now: “I picked up a box turtle and kept it a few days.”

    Now he knows that taking a turtle out of its environment can kill it, and that even if a well-meaning human lets the turtle go, it’s lost without its familiar paths to water, food and shelter.

    Now the Nashville, Tenn., native seeks out – but does not remove – turtles in the pine forests of Weymouth Woods Sandhills Nature Preserve in Southern Pines and Lumber River State Park in Orrum.

    He has attached radio transmitters to some two dozen: little round devices that look like snails stuck to the turtles’ backsides.

    Through them, he learns what routes the turtles take to find food, shelter and mates, and how those routes intersect with human activity.

    He and fellow scientists sought the same kind of information recently when tracking the endangered leatherback sea turtle.

    Roe joined the leatherback study in 2009. He was a postdoctoral student at Purdue University working with Dr. Frank Paladino, an international expert. Roe had already earned an undergraduate degree in biology from Davidson College, a master’s at Purdue studying water snakes, and a doctorate studying freshwater turtles at the University of Canberra in Australia.

    Roe came to Pembroke in 2010 and while there finished work on the paper published in January.

  • N.C.: Pit stop or adopted home?

    On the rare occasion when a mother leatherback nests in North Carolina, is she just making an emergency stop or is she calling North Carolina, however temporarily, home?

    Kelly Stewart of the Ocean Foundation, who has studied East Coast turtles for some time, thinks they may be headed up the coast to forage after laying the majority of their eggs in the popular nesting spots in the Caribbean and south Florida.

    Mama Turtle, she thinks, then realizes she has some eggs left. (One turtle will have about 600 to 700 in a season and will drop them by 80 or so in as many as nine nestings).

    “Oh, wait a minute. I thought I was finished with that,” Stewart imagines the turtle saying, then heading for the nearest beach.

    But Michael Frick of the University of Florida cites repeated visits by Joann, a leatherback he first tagged in 2001 on Georgia’s Wassaw Island and named for his mother. Joann has since been seen at the state’s Blackbeard and Jekyll islands.

    And biologist Jon Altman of North Carolina’s Cape Lookout National Seashore, says that, although leatherbacks don’t visit every year, when one does appear she’ll lay eggs in five to seven different nestings.

    Since 2004, the refuge has had 19 nestings, and those mothers, Altman said, “weren’t just dropping off eggs they forgot.”

You can’t tell a 1,000-pound leatherback sea turtle what to eat or where to nest.

He – or she – will eat the same thing nearly every day of the year: plump, tentacle-streaming jellyfish.

And a female will usually return to the area where she’s always nested, during a life that may extend up to 50 years.

“It was successful for her mother,” explained John Roe, UNC Pembroke biology professor. Even if those beaches are overrun by development or washed away by a hurricane, he says, she will keep on trying.

Nesting beaches are often a continent away from the turtles’ feeding grounds, and they spend several months crossing thousands of miles of ocean to get from one to the other. They’ve been clocked at what for turtles is lightning speed – 22 mph.

The leatherback has a lineage stretching back more than 100 million years. It’s the largest sea turtle, at up to 6 1/2-feet long, and sometimes weighs more than a ton. Its size and the blue-black rubbery skin that serves as a shell make it distinctive.

“If you ever saw a leatherback, you’d never mistake it,” said the Ocean Foundation’s Kelly Stewart, who studies leatherbacks off the Carolinas coasts.

But its instincts, particularly for long-distance travel, are bringing it increasingly in conflict with one of humankind’s ancient activities: fishing.

The same algae blooms that attract jellyfish also attract small fish that are eaten by larger fish. Those larger fish are in turn devoured by the tuna, swordfish and marlin that attract fishing boats, hooks at the ready.

Longline fishing fleets don’t set out to harm turtles, said Roe, who is lead author of one of two recent reports on the locations – and possible collision spots – of leatherbacks and fishing fleets.

But accidental hooking or being tangled in long lines leads to drowning, and this bycatch is considered one major reason that leatherbacks’ numbers in the Pacific have plummeted drastically, as much as 90 percent in the last 25 years, Roe said.

Tracking turtles and boats

In Costa Rica, one of the main Pacific nesting areas, leatherback numbers have dwindled from 1,500 in the late 1980s to a few dozen, he said.

In a 16-year effort, Roe and 13 other U.S. and Costa Rican scientists pooled data from their satellite tracking of 135 turtles migrating across the Pacific. They analyzed data on catches of billfish and tuna, then pinpointed “hotspots” of dual turtle/fishing activity.

Another group of 27 scientists from 13 nations did the same in the Atlantic, tracking 106 turtles. Lead co-authors of that report are Sabrina Fossette, now at the Southwest Fisheries Science Center in California, and M.J. Witt, lecturer at the University of Exeter in the United Kingdom.

The studies were recently published in the journal of Britain’s Royal Society for the Biological Sciences.( http://bit.ly/1ksgrle and http://bit.ly/MKfEgo.)

The idea, said Roe, is to provide broad, general data that hopefully will lead to more specific, localized studies, which in turn will persuade governments and coalitions of governments to provide protection.

For an unknown reason, “the Atlantic populations are doing pretty well,” Fossette said. “Some are stable, and some are increasing.”

But more study and more protection are needed, she said. Though some countries ringing the Atlantic have protections in place, others do not.

A rare sight

A nesting leatherback is a rare sight on Carolinas beaches; there have been eight recorded in North Carolina and 11 in South Carolina in the last five years.

South Florida and the Caribbean are popular nesting spots, and turtles leaving those areas to forage northward make the waters off the Carolinas coast one of the potential hotspots for conflict mentioned in the report.

Protections in place here include turtle excluder devices on shrimp trawlers that are large enough to let leatherbacks escape, and the use of circle hooks, rather than older “J”-shaped hooks, by Longline fleets.

Circle hooks, National Oceanic and Atmospheric Administration biologist Robert Hoffman said, are harder for the turtles to swallow.

When Hawaiian fisheries first substituted fish for squid as bait and started using circle hooks, bycatch of leatherbacks dropped 80 percent, Roe said. For loggerheads, it was 90 percent, and the swordfish catch increased.

Other measures in use elsewhere include closing certain waters to fishing at certain times and the creation of marine protected areas that function like wildlife-friendly national parks.

Roe said the most advanced effort currently is in Hawaii, where a NOAA agency issues electronic advisories to boats, based on satellite information.

It checks currents, algae blooms and weather and tells fleets, “On this date, these are the regions of the ocean where we advise against fishing because there are going to be a lot of turtles out there,” Roe said.

A basis for action

Roe hopes that the information in the recently published reports, when spread by conservationists, will become a springboard for cooperation between governments in affected areas.

Costa Rica and its neighbors already have cooperatively designated their mutual waters as a critical marine habitat, he said.

And in the area of greatest Pacific nesting – Papua, New Guinea, and nearby Indonesian provinces – nations are talking to one another but have no protections in place yet, Roe said. That area and the open ocean southwest of the Galapagos Islands are perceived to offer the greatest risk.

The ultimate goal, Roe said, is to find mechanisms to maintain a balance between an ancient creature’s right to exist and an important human activity.

“Our study is a step in that direction,” he said.

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