Marine mammal experts eye dolphin strandings off South Shore

With a dramatic increase in bottlenose dolphin strandings along the South Shore, marine mammal experts are working to solve the mystery of this summer's unusually high number of deaths in the mid-Atlantic region.

Thirteen bottlenose strandings were reported from Long Beach to Montauk last month, in addition to one in Coney Island and another in the Rockaways, according to a local rescue organization and preliminary data from the National Oceanic and Atmospheric Administration's fisheries service, which is coordinating information gathering. That contrasts with one reported stranding in 2012 and one in 2011.

As for the cause, "right now it's too early to say," said Kimberly Durham, rescue program director of the Riverhead Foundation for Marine Research and Preservation, which has been sending out teams to collect the dead or dying dolphins. Blood results are due back later this week from two dolphins that had to be euthanized in late June and early July, she said.

The hope is to rule out certain maladies, she said, including morbillivirus, which was found to be behind a 1987 kill-off of 740 bottlenoses from New York to Florida, according to NOAA.

That virus was detected in one of July's 20 strandings along the New Jersey coast, with four others attributed to pneumonia, according to a release from that state's Department of Environmental Protection. The causes of death have not been confirmed but "they appear to be part of a natural disease cycle and not related to water quality," the release said.

There were also 42 bottlenose strandings reported last month in Virginia and seven in Maryland, NOAA said.

The dolphins picked up this year in New York have shown "signs of weight loss and parasites," with no indication that water quality issues are at play, said Lisa King, spokeswoman for the state Department of Environmental Conservation.

In mid-July, Virginia and New Jersey reported to NOAA an elevated number of bottlenose strandings, which led to an organized effort to collect, examine and share data, said Maggie Mooney-Seus, NOAA fisheries communications officer. NOAA's network of stranding partners, including the Riverhead Foundation, are required to report data, such as the numbers of animals picked up, she said.

Ultimately, the cause could be the result of "a combination of factors," Mooney-Seus said. "We won't know for a while."

The spate of strandings comes at an unfortunate time in terms of resources for the Riverhead Foundation, the only organization in the area authorized to respond to such calls, Durham said. The group is down to one box truck dubbed the "dolphin ambulance," she said. And its one dolphin rehab tank already has a resident.

Most of the bottlenoses picked up this year were already dead, but with no rehab facility available, one of the two living dolphins had to be euthanized, Durham said.

"We don't have the resources -- they don't exist."