Study to examine dead dolphins in Texas

GALVESTON, Texas - The National Oceanic and AtmosphericAdministration is conducting a special investigation to determinewhat caused an unusually high number of dead dolphins to wash ashorein Galveston and Jefferson counties.The discovery of at least 60 dolphin corpses on the beaches of thetwo Southeast Texas counties this month prompted the National MarineFisheries to declare the occurrence an "unusual mortality event,"said Blair Mase, marine mammal stranding coordinator for NOAA.Nine dead dolphins were discovered in March 2006 and 11 in March2005. Chris Marshall, assistant professor of marine biology at TexasA&M University at Galveston, said the high number of dolphin deathsis alarming because their health can indicate problems in the healthof the ocean.With Tuesday's declaration of the unusual mortality event, Mase saidNOAA will begin necropsies of the animals in which samples are takenof every organ in the body.Mase said lab tests of the dolphins' DNA will help scientists figureout whether the animals come from groups that live primarily faroffshore, as NOAA suspects. The labs will also test for viruses,heavy metals and other toxins. "We don't want to rule anything out,"Mase said.Heidi Watts, operations coordinator for the Texas Marine MammalStranding Network, said she notified NOAA last week of the highnumber of dead dolphins washing ashore during the stranding season,which occurs during the spawning season from January through March.During a normal year, about 180 stranded dolphins wash ashore onTexas' entire coastline. This year, they've been limited almostcompletely to Galveston and Jefferson counties, Watts said. She saidscientists don't know why yet.Scientists believe the dolphins could have drifted from off theLouisiana coast because of their decomposed bodies. Watts said aninvestigation of Louisiana's coastline found only four deaddolphins, all in western Louisiana.Watts said a recent flight by investigators over the Gulf of Mexicoto look for toxic algae blooms and dolphin corpses revealed neither.The declaration of an unusual mortality event is rare. SpokeswomanKim Amendola said NOAA has declared an unusual number of marinemammal deaths eight times since 1988 in a region that includes theGulf of Mexico, the East Coast to North Carolina, the U.S. VirginIslands and Puerto Rico.