* By Steve Patterson
* Story updated at 11:34 AM on Monday, Aug. 24, 2009
Loggerhead sea turtles whose nests line Florida and Georgia beaches each summer could face "quasi-extinction" despite efforts to protect nesting grounds, federal scientists have concluded.
The warning this month to the National Marine Fisheries Service comes as monitoring groups around Florida report an apparent drop in loggerhead nesting this year. The grim news has been compounded by a realization there is probably not a single, easy-to-spot problem wholly responsible for the pattern.
The findings have drawn a dire response from activists.
"This isn't just a problem. This is really a crisis," said Dave Allison, senior campaign director at Oceana, a group that wants more turtle protections.
"We're talking about a trend line that leads to extinction."
Because sea turtles have long lives, an extinction that takes three generations might play out over 100 years. The federal government considers loggerheads a threatened species, one level below endangered.
But scientists said the risk is evident today.
Based on factors such as the survival rates of turtle hatchlings and the number of nests seen over time, researchers assembled by the fisheries service and the U.S. Fish and Wildlife Service forecast circumstances that could push loggerheads into a long downward spiral of shrinking numbers.
The researchers found a "high likelihood of quasi-extinction" in a lot of scenarios for loggerheads along America's Atlantic and Gulf coasts. Worldwide, there were only a couple of places where the turtles' numbers weren't immediately worrisome.
Warning signs have accumulated for some time in Florida, said Anne Meylan, a scientist at Florida's Fish and Wildlife Conservation Commission. She was not part of the federal review team.
Loggerhead nesting fell by more than half between 1998 and 2007 at a core group of heavily monitored Florida beaches, the commission found. Counts rebounded briskly last year, but Meylan said preliminary reports from most of those beaches suggest things are worse this summer.
That pattern has been seen locally, too.
"They're slower this year," said Mary Duffy, president of the Amelia Island Sea Turtle Watch. The 89 nests recorded in Nassau County - all loggerheads - are about 10 percent off last year's pace, she said, and volunteers have had to move an unusual number of nests to keep the tides from covering them.
What's really puzzling, Meylan said, is that other turtles - greens and leatherbacks - are nesting more on the same beaches where loggerheads are vanishing.
Explaining that imbalance "takes us away from the nesting beaches" to look for problems at sea, Meylan said.
"Certainly there is [beach] habitat decline, but that can't explain what we're seeing."
Commercial fishing, dwindling food sources and ocean pollution were suggested as possible factors in research that Meylan and others published this year in a science journal, Ecological Applications.
Those problems don't affect all turtles equally, Allison said. He said loggerheads are more vulnerable to being fatally snagged on long-line fishing hooks, for example, sometimes simply drowning because they can't reach the surface to breathe. Loggerheads nesting in Florida travel from many places, including Mexico, Cuba and the Bahamas, facing obstacles that are different from place to place. Allison said many turtles on the East Coast travel long routes that cross through a series of hazards.
"They're facing a barrage, if you will. It starts in Atlantic Canada. First they face the pelagic long lines. Then they're confronted by the gill nets, then the trawls and the scallopers," Allison said. "It's a real gauntlet that these turtles run."
Because loggerheads don't reach mating age until decades after they're born, researchers have said falling nesting numbers could be the echoes of damage inflicted on turtle populations long before.
"Some of the things we're seeing today on the nesting beaches are probably the result of things that happened ... decades ago," Meylan said.
"If you take 30 years to reach sexual maturity and you suffered a big hit when you were 16, no one knows it until you hit the nesting beach."
steve.patterson@jacksonville.com,
(904) 359-4263
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