RESEARCHERS LOOK FOR THE CAUSE OF TUMORS IN FISH
By Frank Adams
Two Florida State University researchers are trying to discover the cause of grotesque tumors - reminiscent of the Elephant Man in the movie, but on fish instead of humans.
Robert Werner, an FSU animal researcher, is studying the problem with FSU biologist Gregg Stanton.
Tumors can grow all over fishes bodies and eventually kill them.
Werner and Stanton have tracked the disease in gray snappers, also called mangrove snappers, which are edible. But they say they have no reason to believe that people can catch neurofibromatosis by eating fish that have it.
Gray snapper are part of the state's commercial fishery, and generated an average of $879,885 in revenues for commercial fishermen in Florida each year for the last five years.
The FSU researchers aren't sure what's causing the tumors in mangrove snapper and bicolored damselfish.
"It could be environmentally induced," said Stanton, who is head of FSU's academic dive program. "It could be due to rising temperatures in the waters around the Keys. But it also could be caused by genetic factors in the fish, or it could be spread infectiously through the fish populations. We don't have enough data to really determine the cause."
Stanton, Werner and student assistants have studied the disease for three summers. They have scuba dived the waters between the Florida Keys and the Dry Tortugas to find infected fish.
Since bicolored damselfish live in well-defined home territories, it's easier to count the number to get the percentage affected by the disease. In some areas between the Dry Tortugas and the Florida Keys, Stanton said, 30 percent of that kind of fish had tumors.
But gray snapper range more freely through their fluid habitat, and the researchers sometimes found it difficult to find many of them.
But they had help from commercial fishermen, who told them where they could find plenty of gray snapper to study, as long as the researchers promised not to reveal the anglers' hotspots.
Werner said the percentage of gray snapper with tumors varied from none up to 6 percent, but that it was still too early in the study to draw conclusions.
While searching for snappers with tumors, the other researchers on this project found something else disturbing black spots on the sides of the fish, which are caused by parasitic worms, possibly a new species.
"Where do we go from here?" Stanton asked. "We keep going back down to the islands until we find some answers."