11 November 2005

USA: Hurricanes drive sea turtle nesting numbers to historic lows

It wasn't the kind of record-breaking year sea turtle observers were hoping for across Southwest Florida.

"It was our lowest nesting season we have ever seen," Maura Kraus, Collier County's principal environmental specialist, said.

A barrage of hurricanes that struck or just missed the region drove the number of loggerhead nests on Collier and south Lee beaches to historic lows, environmental officials said. The six-month-long season ended Monday.

Other theories abound. Some think sea turtles' productivity rises and falls naturally. Others believe red tide is playing a role. And others speculate the influx of condominiums, homes and other buildings along the coast has forced turtles to hunt for more secluded egg-laying grounds.

Whatever the cause, the threatened species' numbers continue to fall at an alarming rate.

From Cape Romano to Barefoot Beach, observers counted 444 nests, down 206 from last year. The most nests ever recorded on Collier County's beaches was 1,135 in 1998, and the previous low was 611 in 2002, according to county records.

In south Lee County, loggerheads formed 46 nests on Bonita Beach, Big Hickory Island and Fort Myers Beach, down 61 from the previous year, according to Turtle Time Inc., which monitors turtles.

Bonita Beach has faced a dramatic decline in nesting, said Eve Haverfield of Turtle Time. From 2000 to 2004, an average of about 71 nests were discovered on the densely populated, 2.5-mile stretch of sand. This year, the total fell to 24.

"My hope is that it's not a permanent or ongoing trend," Haverfield said. "Loggerhead nesting is cyclical in nature."

Weighing between 250 and 400 pounds, female loggerheads lug themselves onto dry sand generally between May and August each year to dig their nests. The annual count of nests, including those that hatch, indicates whether the massive turtles are thriving.

Statewide figures for loggerheads won't be available until the end of this month, but the prognosis isn't good, Kraus and Haverfield said.

"The trend in Florida for the last five years, for the loggerhead nests anyway, has been on a downward slope," Haverfield said.

Scientists believe that the worst red tide outbreak in more than 30 years killed dozens of sea turtles this summer, particularly in the Gulf of Mexico's waters off Pinellas County. The bloom has dissipated in recent weeks.

Rain and storm surge from passing hurricanes drowned dozens of sea turtle nests, officials said. On Lovers Key, loggerheads dug nine nests, all of which were destroyed by Hurricane Dennis.

"Dennis took care of them all," said Lovers Key/Carl E. Johnson State Park Assistant Manager Heath Alboher.

Hurricanes also wiped away sandy beaches that were once popular nesting grounds. In August 2004, Hurricane Charley eliminated Morgan Island, near Cape Romano.

This year, Collier observers counted 35 nests on and around Cape Romano, but none hatched. Overall, the number of hatched nests rose this year compared with last year in Collier County, from 185 to 282.

Observers are still totaling the number of baby turtles that emerged from each nest. The nests typically hold between 80 and 100 eggs.

Even if nests in Collier and south Lee produced on the lower end of that scale this year, there could be 25,600 hatchlings plying the Gulf.

The end of turtle nesting season means condominiums and other buildings on the beach can open their drapes at night and shine security lights toward the water. A widely adopted law bars excess lighting during the season because it can disorient turtles.

Source: http://www.knoxstudio.com/shns/story.cfm?pk=SEATURTLES-11-02-05&cat=AN


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