WASHINGTON - At least 164 dead dolphins have been counted so far this year in Virginia, up from 100 just two weeks ago.
The mysterious deaths of dolphins is a recent trend stretching all along the East Coast, and researchers in Virginia are part of an urgent effort to pinpoint the cause.
"We are finding that these dolphins are extremely sick. Some of them are very thin, some of them have lesions internally and externally. We're finding infection in their lungs and perhaps also in their bones. I'm not saying each dolphin has that, but that's kind of a spectrum of some of the things that we've seen," said Joan Barns with the Virginia Aquarium and Marine Science Center in Virginia Beach.
"It appears to be some kind of an infection that's attacking these dolphins, and whether that's the ultimate reason for their death or just the secondary cause is hard to determine. You have to remember that dolphins are extremely social animals. So we think this is an airborne virus that they're passing to one another. That's still yet to be determined," said Barns.
"It may not be a single cause. We just don't know at this point," she added.
Most years, about 65 dead dolphins are found in the surf. Marine biologists say dolphin strandings historically peak in May and June. In July, however, 44 dolphins were found dead. Most were discovered in the southern part of the Chesapeake Bay. Delaware and Maryland have also seen an uptick in dolphin deaths.
The center's Stranding Response Team is in charge of responding to stranded marine mammal or sea turtles found along the entire Virginia coastline.
She says her facility has been very busy performing necropsies on the most recent batch of dead dolphins.
"It can take four members up to eight hours to perform a single necropsy," Barns said.
Tissue samples are taken and sent off to pathologists for additional testing that can take weeks or even months.
"We are also working with other stranding network teams that are sending members up here to conduct the necropsies. And we've also had a couple members from the Smithsonian Institute that are helping us as well." said Barns.
Barns says responding to the unexpected die-off has been a challenge.
"It's certainly overwhelming our staff. It is stretching our ability to the limit. It's also affecting our funding. We have basically used up our funding for marine mammal stranding this year, and unfortunately, a lot of our funding comes from the Prescott Grant, which is tied to NOAA, and that is a fund that is projected to be cut due to sequestration in 2014," Barns said.
"Back in '87 we had a similar event with what they call the dolphin die- off, and we lost a bit of our dolphin population all along the East Coast. And we're trying to determine if that's a similar event that's happening here."
Scientists say they think that die-off was caused by morbillivirus.
Barns said solving the latest dolphin death mystery is crucial.
"Dolphins, not only are they iconic, but they are also a higher predator in the ocean and they serve as sentinels for the ocean health. So as fellow mammals, it's important to know what is affecting their health," she said.
Barns says if you see a dead or dying dolphin in Virginia, don't touch it, but do report it to the aquarium's 24-hour hotline: 757-385-7575.
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