Death in The Mediterranean

The first hint that something was wrong came in August, when dead dolphins -- victims of pneumonia and liver damage -- began washing up on Mediterranean beaches near Valencia, Spain. But until the past few weeks, no one had | realized the extent of the disaster. When scientists from European countries began comparing notes, it suddenly became clear that some sort of epidemic was raging through the striped dolphin population of the western Mediterranean Sea. In France, where dead dolphins usually wash ashore at a rate of about 50 a year, 50 were discovered in a two-week period, and the toll in Spain is up to 250 in less than three months. Since it is possible that only a small percentage of dead animals have drifted in to land, the actual toll may be much higher.

It did not take long to track down the source of the infection. Laboratory tests revealed that it is a strain of morbilli, the same type of virus -- similar to the cause of canine distemper and human measles -- that killed some 20,000 North Sea seals in 1988. While viral epidemics are part of the natural ecology of the sea, some scientists think this outbreak was aggravated by man-made pollution. Autopsies on the mammals show their tissues are contaminated with metals and the toxic polychlorinated biphenyls (PCPs). The chemicals may have weakened the dolphins' immune systems, making the animals more vulnerable to disease.

This would not be the first time such a link between pollution and plague has shown up. In a 1988 report to the U.S. Marine Mammal Commission, investigators suggested that a rash of dolphin deaths on America's East Coast might have resulted from bacterial infections that overwhelmed the animals' pollution-damaged immune systems. Environmentalists believe the Mediterranean case is potentially more serious, since it is happening during fall, one of the dolphins' prime breeding seasons. The disease could also spread to other mammals, including monk seals, pilot whales and sperm whales.

Unfortunately, the Mediterranean is so filthy that even a major cleanup effort would make little difference for years. The animals may not have that much time. There is no known cure for the virus, and scientists and environmentalists alike fear that dolphins could become no more than a memory in the Mediterranean.