Agency Notes Rise in Dolphin Deaths

A dolphin that washed ashore in Long Beach on Monday was the third mammal of its kind found along the city’s shore in recent days and among a growing number of fatalities of a particular species this summer.

The washed-up bottlenose dolphin was discovered on the beach between Monroe and Long Beach boulevards at about 12:30 p.m. July 29, a Long Beach resident told Patch. 

“There were no outward signs of being struck or injured,” he wrote in an email about the mammal’s appearance.  

The Riverhead Foundation for Marine Research and Preservation, a nonprofit agency that recovers any marine mammals or sea turtles that wash ashore in New York State, retrieved the bottle-nose dolphin in Long Beach, as well as another of the same species in Rockaway, on Monday, and conducted an autopsy on both creatures the next day. Kim Durham, a Riverhead Foundation rescue program director, who performed the procedures, said the dolphin found in Long Beach was a male, approximately a year old, which suffered from a respiratory disease.

“It did have a pretty significant lung infection and it was very underweight and had an empty stomach,” said Durham, who added that she took tissue samples from the animal which, through further tests, could reveal the source of the infection. The dolphin retrieved from Rockaway, she said, was a male that had parasites and adhesions within its intestinal tissues, “which is evidence of a chronic infection."

Meanwhile, two other dolphins were found on local beaches, one last week and another last Saturday, according to the City of Long Beach. Of the latter dolphin, tides took it back out to sea before it could be retrieved, but photos revealed it was not the same dolphin found Monday, Durham said.

Earlier in July, a basking shark washed ashore on a West End beach in Long Beach, and a dolphin that was stranded near Jones Beach died. On Tuesday the Riverhead Foundation was informed that two more dead bottle-nose dolphins were discovered, one in Breezy Point and the other in Fire Island Inlet.

Durham reported a marked increase in dolphins that have washed ashore this summer, not only in New York but also in New Jersey and Virginia. While the agency in New York responded to three dolphins that washed ashore from June 23 to July 31 in 2012, that number for the same time period this summer had jumped to 15.

Durham called the increase “a big difference,” but was quick to note that it could have multiple causes, which the agency has yet to determine.

On examining a washed-up bottlenose dolphin, Durham said, she first tries to determine whether the mammals demise was due to a natural fatality or a byproduct of a fishery interaction, usually when an animal gets ensnared in a fishing net, before looking for indications of disease.

The resident who contacted Patch about the dead dolphin Monday expressed concern about the water quality in Long Beach, since he and his young daughters swim and surf in the ocean almost daily, and especially after Hurricane Sandy and the excessive rawsewage spills from the Bay Park Sewage Treatment Plant into Reynolds Channel.

“[I]n the four years we've lived here, this is the first time we've seen anything larger than a horseshoe crab wash up,” he said. “I also notice there are fewer mollusks and crabs this year, a lot more seaweed, and many fewer seagulls. I don't know how much of this is attributable to the after effects [of] Sandy, but it is enough in the aggregate to give me pause.”

But Mary Ellen Laurain, a public information officer for Nassau County, said the Department of Health tests beaches on a routine basis to determine water quality, and that, at least for humans, the water is safe.

“A test was performed last week and all readings at locations in and around Long Beach are above federal and state standards for bathing water quality,” Laurain said.

Durham said people typically point first to water quality as the possible cause of washed-up dolphins and other sea creatures. But other potential factors, including viral or bacterial infections unrelated to the water, as well as an increase in the mammal population, could explain the increase. She said that a whale-watching organization has reported a significant increase in whale and dolphin sightings in New York Harbor this year. 

Because of such reports, she is not alarmed yet by the increase number of dolphin deaths.

“If the population is big, then you’re going to see a certain percentage of that population that is going to be sickly, whether it be of the young or the old,” she said. “Right now we’re trying to figure out whether there is anything connecting all of the animals [that have washed up], and so we have our hands full with that.”

The Riverhead Foundation asks that anyone who spots a dolphin or other marine mammal that has washed ashore to call the agency at 631-369-9829.