 FLORIDA'S CANARY IN THE COAL MINE Palm Beach Post -- Wednesday, July 25, 2001 By: Sally Swartz, Palm Beach Post Staff Writer This has been a good week for Megan Stolen, a Hubbs-Sea World Marine Institute biologist. No more dead dolphins have washed ashore in the Indian River Lagoon near Melbourne. She hopes that means the deaths - 27 since the end of May along a 25-mile stretch of the lagoon - have stopped. What killed the animals, most of which were extremely emaciated, remains a mystery. "We've been looking for infectious disease, viruses, toxic problems," Ms. Stolen said. "At this point, we're trying to rule out things that are not the causes." Because fish died in the same area, she has kept in touch with Florida Marine Research Institute scientists, who said the fish kills were caused by low levels of oxygen in the water. Dolphins, which breathe air, wouldn't have been affected by an inadequate supply of oxygen in the water, but they might have suffered from a drop in the food supply. Ms. Stolen awaits results from tests on tissue samples from the dolphins, but there are no clues. Was it runoff from the first heavy seasonal rains after the long drought, runoff that was poisoned with pollutants? No data support that theory. Why are all the dolphins so skinny? Is it a chronic condition or did some unusual event render them unable to feed themselves? Could it be red tide or a viral outbreak, linked to dolphin die-offs in Florida's Panhandle or the Keys? It's a mystery, Ms. Stolen repeats. In fact, the U.S. Marine Fisheries Service has declared the series of deaths an "unusual mortality event," which allows scientists to tap into resources and research money to help solve it. It is not the first mystery that scientists studying dolphins and Florida's other marine mammals have confronted. Greg Bossart, director of marine mammal research at Harbor Branch Oceanographic Institution in Fort Pierce, is disturbed by what he sees. "We never have seen such diseases," Mr. Bossart said. "New forms of cancer, highly malignant, in free-ranging dolphins." Skin disease and a hepatitis B-type virus have been identified in coastal dolphins. Mysterious deaths such as the Indian River Lagoon event seem to occur every few years. Manatee deaths on Florida's west coast a few years ago were blamed on red tide, a bloom of harmful algae in the water that can affect people as well as fish and sea mammals. Red tide also was blamed for the 1999 deaths of 25 Panhandle dolphins. Scientists never were able to agree on what killed more than 1,000 bottlenose dolphins along the Eastern seaboard about 14 years ago. Some blamed red tide that got into fish the dolphins ate. Others blamed a virus. Still others said chemicals such as dioxin and DDT-related compounds, which are found in runoff from farms and cities and can accumulate in the liver and kidneys of marine mammals, weakened the dolphins' immune systems. Harbor Branch has proposed an $8 million manatee research and education center as the first segment of a $25 million marine mammal teaching and research hospital. The center's first research project would examine a tumor-causing virus in manatees. "To me, the things we are seeing in marine mammals are red flags," Mr. Bossart said. "We may be seeing some sort of environmental distress syndrome. The bottom line is, dolphins, whales and manatees are like the miner's canary in the coal mine. What has happened to them is going to impact us." Though scientists have no verdict on why the Indian River Lagoon dolphins died, Ms. Stolen said for now she is "knocking wood. We hope it's over." Mr. Bossart, meanwhile, wants to start research soon. "It's not from a tree-hugger's aspect," he said. "It's in our own best interest to find out what is happening to marine mammals -- and to do it quickly." Copyright (c) 2001, The Palm Beach Post |