The National Oceanic and Atmospheric Administration has declared an "unusual mortality event" for the mid-Atlantic region, with July seeing more than seven times the average number of bottlenose dolphin strandings for the month, said the national marine fisheries service.
Topping the list of potential causes is an infectious pathogen, this based on the quickly increasing number of deaths and "geographic extent" of the problem, from New York to Virginia, said the news release from the National Oceanic and Atmospheric Administration.
Still, "there are no unifying gross necropsy findings," and "all potential causes," including possible viruses, bacteria, fungi and biotoxins, are being studied, the release said.
Declaring a mortality event means added federal funding toward the costs of the strandings, including reimbursing rescue groups that prepare and transport samples for testing, according to the release. Also, a team of scientists is being named to help develop a response plan, with the investigation taking possibly months to years, said the release.
Last month, 13 bottlenose strandings were reported on Long Island from Long Beach to Montauk, along with one in Coney Island and one in the Rockaways, according to the Riverhead Foundation for Marine Research and Preservation, which sends out teams to collect the dead or dying dolphins. That contrasts with one reported stranding in 2012 and one in 2011.
Another eight bottlenoses were picked up in the first 10 days of August, from the Rockaways to East Hampton, said Rob DiGiovanni, the foundation's executive director.
While one dolphin found last month in New Jersey indicated the possibility of morbillivirus, NOAA said it's too early to pin the increase in deaths on that infection, which was behind a 1987 kill-off of more than 740 bottlenoses from New York to Florida.
Also, there's no indication that water quality issues are at play, said Lisa King, spokeswoman for the state Department of Environmental Conservation.
So far, bottlenoses are the only marine mammals affected, no link has been found to "seafood safety issues" and "no cases of human illness have been reported," the release said.
As for the Riverhead Foundation, the die-off is adding "a huge load" to an already stretched organization, DiGiovanni said.
Down by $150,000 in funding the past three years, the group has had a record number of sea turtles in rehab, and is caring for Roxanne, a Risso's dolphin, in its only dolphin rehab tank.
"We just have to believe that people are there and that they care," he said.