still craving Gulf seafood?

I don’t know if I’ll be partaking, what with all the dead dolphin calves washing ashore

‘Trying to find out what’s going on here’
Infant dolphin deaths are up on Gulf Coast and scientists want to know why

By KAREN NELSON – klnelson@sunherald.com

GULFPORT — Four baby dolphins lay dead in the sand on the south side of Horn Island and one on Ono Island off Orange Beach, Ala., Tuesday.
That’s more dolphins dead in one day than all the dolphins, of any age, found dead in Alabama in 2008.
And those that are washing up this week along the shores of Mississippi and Alabama are all babies, either stillborn or very young. The total is 19 calves from mid-January to present, nine of those in just the last 10 days.

“With some, we’re not sure if they actually took a breath,” said Dr. Delphine Shannon. Shannon handles strandings for the Institute for Marine Mammal Studies, the agency that collects data on dolphins and sends daily reports to NOAA’s National Marine Fisheries division.

This is all happening early in the birthing season, which gets into full swing in March. The early deaths indicate something is wrong, said Moby Solangi, director of the institute.

With the Coast living in the shadow of the BP oil spill, the deaths bring an acute awareness to the situation. But scientists aren’t laying any blame until test results come back, and tissue samples haven’t even been sent to a laboratory yet.

The spike in infant dolphin deaths has the attention of both NOAA and the state Department of Marine Resources.

“Our antennas are up,” Solangi said. “I believe we’re going to see a correlation with something. This is too big a shift.”

So far, four calves in January and 15 in February have been found dead along Mississippi and Alabama shores.

Compare that with the two years before the oil spill, when one death each was reported in Mississippi — both in February.

The numbers for carcasses of all ages of dolphins found in the two states by year, according to Solangi and Marine Fisheries data, is 29 in 2006, 13 in 2007, 21 in 2008 and 45 in 2009. Then 89 were reported in 2010, and 28 in just the first two months of this year.

Blair Mase, NOAA’s stranding coordinator for the region, said her agency is watching the situation and comparing previous years’ data, “trying to find out what’s going on here.”

“We’re trying to determine if we do in fact have stillbirths,” Mase said.
The BP oil spill spewed more than 200 million gallons of crude oil into the Gulf during dolphin mating season in 2010 and through months of the early gestation period, which is about a year. Thousands of gallons of dispersant was used to break the oil into droplets and suspend it in the water column.

But scientists are not jumping to conclusions.
Solangi’s crews have collected skin, blubber, muscle and organ tissue from six to eight of the calf carcasses that were fresh enough for good test results. Solangi said he was hoping to coordinate with government agencies and select the best labs for very specific testing.

Some will be university labs, others will not. They will be testing skin samples for genetics and DNA, the blubber layers for heavy metals, and organs and muscle layers. Tissue will be tested for hydrocarbons, insecticides and pesticides as well.

“We normally don’t do such broad testing,” Solangi said. He said he hopes the federal government will pick up the tab.
On Tuesday, only one of the calf carcasses that washed ashore on Horn Island was in good enough condition to bring back for a necropsy, which is an animal autopsy. It was a little male that had been dead for only a day or two and had just begun to bloat.

U.S. Fish and Wildlife Service biologist Megan Boldenow had reported all four on the island while doing her daily beach walks and bird surveys. Her job is to oversee BP oil-recovery workers as they sift the sand on Horn Island for tar and oil residue.

Three of the calf carcasses were badly decomposed. They were left on the beach after a team of four from the institute took tissue samples, photographed the bodies and tagged them.

Boldenow wondered if the high number of baby carcasses reported might have something to do with more eyes being on the beaches since the spill.

The Gulf and the Mississippi Sound is the nursing, breeding and birthing area for the bottlenose dolphin.

Solangi called them a biological indicator in the environment and said when something is wrong in the population, being at the top of the marine food chain, it could be a warning sign. The young are the most vulnerable, he said.

Bill Walker, head of the Mississippi’s DMR said this week, “Yes, something’s going on …. For some reason it looks like the mothers are aborting these youngsters before they can survive”.

Of course the culprit could be a number of things or a combination of things, including biotoxins, water temperature, infections and feeding patterns, scientists have said.

“I’m just trying to stay abreast of this,” Walker said. “Could be environmental. Could be anything.

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~ by maringouin on Friday, February 25, 2011.

 
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