Dolphins are severely threatened by a growing number of diseases deriving from contamination of the oceans. During the last year numerous peer-reviewed scientific papers have been published documenting a worldwide surge in incidence of diseases heretofore unknown in dolphins. A team of researchers and veterinarians from the Marine Animal Disease Lab at the University of Florida have discovered at least fifty new viruses in dolphins. Their exponential increase is due to their body burdens of high levels of organic pollutants such as PCBs, PBDEs, DDT, and other chemicals that suppress mammalian immune systems and disrupt normal endocrine function. Some of these chemicals are known to be estrogen imitators that act to feminize males and superfeminize females.
In addition, resistance to antibiotics has been found in dolphins in numerous locations around the world. Obviously antibiotics do not occur naturally. They derive from people and animals who take antibiotics and introduce them into the ecosystem through bodily elimination or simply throwing unused pills away. After they reach the watershed plankton ingest them and they bio-accumulate up the food web to concentrate in top predators such as dolphins. Something alarming the Centers for Disease Control (CDC) is the fact that dolphins resistant to antibiotics have the potential for breeding super bugs that may pass back to humans. The transmission of disease from one species to another is called zoonosis. AIDS is one example of zoonotic transmission.
If Japan stopped whaling and dolphin hunting now it would appear environmentalists had forced them to back down, something a proud and insular nation cannot tolerate. But the knowledge that diseases such as brucellosis and papillomavirus are being found ever more frequently in dolphins may, ironically, be what forces the end of eating dolphin meat.
It baffles me that whaling and dolphin killing can persist in the 21st century. We know so much about these magnificent animals. Whale and dolphin watching generate over US$2.1 billion per year around the world, vastly more than whale and dolphin killing.
In the light of emerging threats to the marine ecosystem, dolphins and whales in particular, the deliberate killing of these curious, intelligent, sentient animals is tragic and will only hasten the extirpation of whole populations of these magnificent sentinels of the sea. But what is happening to dolphins is clearly a harbinger of what confronts humanity.