Longest Recorded Nesting Leatherback Sea Turtle Returns To Nest

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Rafe Boulon with “Snagglepuss,” first seen and tagged (AAG 347) on Sandy Point, St. Croix, in 1979 and last seen there in 1998, when the photo was taken.

Leatherback returns to Sandy Point and sustains head injury

Scientists at the Sandy Point National Wildlife Refuge (SPNWR) were thrilled to encounter an old friend nesting on the beach this year.

Leatherback sea turtle number AAG322, first observed in 1981 returned 31 years later to lay another nest at SPNWR.

“Other projects studying nesting leatherbacks have recorded females returning to beaches for 18 and 19 years but none of them coming close to 31 years,” said SPNWR biologist Claudia Lombard.

AAG322 has returned many times through the years to lay a total of 59 nests at Sandy Point, a fact that is known thanks to the consistent monitoring efforts of many different scientists and volunteers.

Every leatherback that nests at SPNWR receives a flipper tag with a unique number so that scientists can track individual turtles through time as well as assess the population status.

“Although AAG322 is the turtle that has been coming to Sandy Point for the longest time, there are a couple of other turtles that are not far behind her,” said Jennifer Valiulis, director of the sea turtle project for Geographic Consulting, the group which currently does the sea turtle monitoring at SPNWR.

Each year between 90 and 200 leatherback turtles migrate from feeding grounds in the North Atlantic to nest at SPNWR on St. Croix. SPNWR hosts the largest nesting population within United States jurisdiction and in the Northern Caribbean.
The leatherback sea turtle recovery program at SPNWR began monitoring and protecting turtles in 1977 and has since developed into one of the most unique, long-term sea turtle research and recovery efforts in the world.

The number of nesting females has grown from under 20 in 1982 to more than 100 in most recent years. The 2009 nesting season set a record with 202 nesting females and over 1000 nests.

The endangered leatherback sea turtle is the largest, deepest diving, most migratory, and widest ranging of all sea turtles. The leatherback turtle is distributed worldwide in tropical and temperate waters of the Atlantic, Pacific, and Indian Oceans.

It is also found in small numbers as far north as British Columbia, Newfoundland, and the British Isles, and as far south as Australia, Cape of Good Hope, and Argentina.

Throughout this entire range, the leatherback sea turtle is considered endangered. Adult female leatherbacks migrate to tropical sandy beaches to nest every two to three years.

Females emerge from the ocean at night and lay approximately 80 to 100 eggs deep in the sand. They nest an average of 5 to 6 times each season, typically at 10-day intervals.

The excitement of this new record is diminished by the fact that the turtle later suffered a serious head injury. When scientists first saw AAG322 this year nesting on March 16 she appeared healthy.

Only two weeks later she emerged to nest again, but this time had multiple wounds to her head, mostly around her eyes. These wounds appeared to be caused by a boat propeller. She was able to lay one more nest about 10 days later, her last of the season, and scientists documented a rotten smell coming from her wounds.

“Wounds from boat propellers are not uncommon here, and her’s were especially severe,” said Valiulis.

A disturbing increase in the number of boat strike injuries to sea turtles has been documented at SPNWR.

All sea turtles spend time at the surface breathing, basking in the sun, and searching for suitable beach nesting habitat. At these times, sea turtles are very susceptible to boat traffic.

Sea turtles can be seriously injured or killed if hit by the hull of a boat or a boat propeller. Boats operating erratically or at high speeds do not allow turtles enough time to dive and avoid a boat.

Lombard and Valiulis urged boaters to operate boats responsibly and at safe speeds to protect sea turtles, especially when driving close to nesting beaches or foraging areas.