The largest accidental marine oil spill in the history of the petroleum industry has had no apparent effect on the sea turtle population that migrates to Cape Cod waters, according to Dennis Murley, Naturalist at the Wellfleet Bay Wildlife Sanctuary.
Speaking to approximately 400 participants of the 18th Annual Cape Cod Natural History Conference at Cape Cod Community College today, Murley says the record number of sea turtle strandings on Cape beaches last year show the oil spill had minimal, if any impact on the turtle population.
"It takes two years for a sea turtle to mature and migrate to northern waters," Murley told the audience of mostly scientists. "If the oil spill had kept the numbers down in the Gulf, we would have seen fewer sea turtles in Cape Cod Bay this year. Instead", he says, "there were more than ever".
In recent years sea turtles -- including loggerheads, leatherbacks, exceedingly rare kemps ridley and greens, have migrated farther north than before. Murley says there used to be ten cold-stunned sea turtles in the waters off Cape Cod, and several hundred off Long Island. Now, he says, it is the reverse, a phenomenon he attributes to rising sea temperatures.
In 2010 the Deepwater Horizon oil rig exploded and sank in the Gulf of Mexico, spewing crude oil unabated into the Gulf for 87 days before crews found a way to cap it. Environmentalists predicted a catastrophe for marine life. Last year's record sightings and strandings of sea turtles show that the juveniles which were hatched in the gulf were healthy enough to make the northerly trip to Cape Cod waters as two year olds.
For leatherback turtles, our abundant jellyfish supply in Buzzards Bay is a major lure. Murley says loggerheads are the only predator of jellyfish in the world, yet they pay a price.
"We see them with swollen eyes, all puffed up from getting stung by the food they eat". He likens the thrill of a leatherback eating a jelly fish to a human eating hot peppers.
One thing that affects all sea turtles is the life-threatening shock experienced when they fail to go home again before the relatively shallow water around the Cape quickly turns cold in the fall.
Thanks in part to volunteers, the New England Aquarium and the National Marine Fisheries Service, hundreds of cold stunned sea turtles have been rescued, rehabilitated and outfitted with GPS tracking devices, which often fall off before the turtle dies of old age. Some sea turtles can live to 100.
Murley says medical science deserves the credit for the high percentage of successful rescues. "There have been great advances in the field of cold-stunned medicine in recent years" Murley says.