The U.S. National Marine Fisheries Service has declared an Unusual Mortality Event for bottle nose dolphins in the Mid-Atlantic region from early July 2013 through the present. Elevated strandings of bottlenose dolphins have occurred in New York, New Jersey, Delaware, Maryland and Virginia.
Current bottlenose dolphin strandings are over seven times the historical average for the month of July for the Mid-Atlantic Region. All age classes of bottlenose dolphins are involved and strandings range from a few live animals to mostly dead animals with many very decomposed.
There are no unifying gross necropsy findings although several dolphins have presented with pulmonary lesions. Preliminary testing of tissues from one dolphin indicates possible morbillivirus infection, although it is too early to say whether or not morbillivirus may be causing this event. Based on the rapid increase in strandings over the last two weeks and the geographic extent of these mortalities, an infectious pathogen is at the top of the list of potential causes for this UME, but all potential causes of these mortalities will be evaluated. Work is underway to determine whether an infectious agent affecting these dolphins is present in collected tissue samples.
As part of the UME investigation process, an independent team of scientists is being assembled to coordinate with the Working Group on Marine Mammal Unusual Mortality Events to review the data collected and to determine the next steps.
Click here for NMFS’ website on dolphin UME.