 |
| credit: Riverhead Foundation |
Update: A virus similar to measles could be the reason for the extraordinary increase in bottlenose dolphin deaths on the eastern seaboard.
[photo: Long Island, NY] NOAA and university experts have tentatively attributed the ten fold increase in mortality to cetacean morbillivirus. While there are vaccines for land animals, there is none available that could be easily administered to wild dolphins. The deaths are the highest number in 25 years. The outbreak could last until May of next year if it follows the course of a similar outbreak in 1987-88. The virus debilitates dolphins' immune systems making them vulnerable to other diseases such pneumonia. Experts are monitoring an area off the coast of Georgia where there are high levels of PCBs, a known carcinogen in humans and mammals, since dolphins migrate south in winter.
Mid-Atlantic states are reporting a spike in bottlenose dolphin deaths that has prompted the declaration of an unusual mortality event under the Marine Mammal Protection Act of 1972 (MMPA) beginning in July. Bottlenose deaths have increased along the Atlantic coast from New York to Virginia
[chart] to more than seven times the historical average for this time of year. Marine mammalogists suspect a disease pathogen that is infectious given the extent of strandings in number and geographic spread. Most of the stranded animals are found dead and decaying, but a few are found alive. Several dolphins have presented pulmonary lesions and preliminary testing of tissues indicates possible morbillivirus infection, but it is too early to make a definitive diagnosis. It has been twenty-five years since the last major mortality event when the dolphin morbillivirus killed more than 740 dolphins. That event together with a humpback whale die off prompted Congress to formally establish the Marine Mammal Health and Stranding Response Program which is now part of the MMPA (Title IV). Work is underway to collect tissue samples and isolate the cause of mortality, if possible.
