Threats to Florida sea turtles on the rise

September 2, 1998
Webposted at 3:40 PM EDT

By Environmental News Network staff

Papillomas is a potentially fatal disease that causes tumor-like growths on the soft tissue of sea turtles.

(ENN) -- Both the numbers of sea turtles documented to have perished from a boat-related injury and the number of sea turtles found with a deadly, tumor-causing disease are on the rise.

Of the 566 sea turtles found dead between January and June along Florida's shores, more than one-third of them showed signs of boat-related injuries. The percentage of those found to have the tumor-causing disease fibropapillomatosis is up 40 percent.

"We are concerned about the large increase in the number of sea turtles with boat-related injuries," said Allen Foley, Florida Marine Research Institute strandings coordinator. "It is possible that we are better able to identify boat- related wounds, but the numbers seem overly high for that to be the only reason for the increase."

While boat registrations in Florida have been steadily increasing at about three percent a year, the increase is not dramatic enough to be the reason for the rise in sea turtle injuries either, said Dan Evans of the Sea Turtle Survival League.

"It could be related to this year being a high nesting year. Records are being broken for the number of nests on nesting beaches," said Evans. "There could be more turtles in the water and more people on the water."

Sea turtles, which are reptiles, don't usually spend much time at the surface of the water. A turtle will rise to the surface, take a fresh breath of air, and then dive back down. But occasionally they may spend several minutes at the surface taking multiple breaths, making them more vulnerable to being struck by a boat.

Sea turtle habitat is the same as manatee habitat and boaters should be aware when they are in such places, said Evans. "It doesn't hurt to slow down a little," he said.

The rise in fibropapillomatosis, known as papillomas, is also sounding an alarm for researchers. Papillomas is a potentially fatal disease that causes tumor-like growths on the soft tissue of sea turtles. The growths often cover the eyes of the turtles, causing blindness, which can lead to slow starvation because the turtles can't see to find food.

Researchers studying sea turtles in the Indian River Lagoon are finding that more than 70 percent of the juvenile sea turtles there have the disease. Water pollution may be linked to the occurrence of papillomas.

"There is strong evidence to suggest the disease is related to a toxic algae that is more common in polluted waters," said Evans.

The waters are primarily polluted by runoff, an issue that effects other marine animals and humans as well, said Evans.

"Boaters can be educated to watch out for sea turtles in the water," said Evans. "But we don't yet know what's causing this disease, and this disease is killing sea turtles."

In the final week of the 1998 Florida legislative session, state lawmakers passed a resolution recognizing the serious threat papillomas poses to the state's endangered sea turtles. The resolution also called for more funding to study the causes of the disease.

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