EVERGLADES NATIONAL PARK, Fla. (AP) -- Pods of 35 pilot whales slowly swam Thursday into deeper water off Florida's southwest coast, raising optimism that the strandings of whales on Everglades National Park beaches may soon end on a positive note.
National Oceanic and Atmospheric Administration fisheries official Blair Mase said midafternoon Thursday that the three whale pods were nine miles north of their original location and continuing to move offshore. They were in 18 feet of water about six miles offshore, still several miles from the 900-to-1,000 foot depths they usually call home, Mase said.
"They are in deeper water, and they are getting closer to their normal home range," Mase said. "Even though we are hopeful, this situation could go either way. There is a chance they could come back inshore again."
Mase said the total of dead whales has reached 11, with five still unaccounted for. She said wildlife workers were surprised Thursday morning to discover that most of the live whales had moved out of the shallows on their own sometime during the night. By early evening Thursday, most crews had left the scene, but a Coast Guard cutter was to remain stationed with the whales overnight Thursday.
About 15 vessels carrying about 35 personnel were involved in the effort to track the whales, which were first spotted Tuesday in extremely shallow water in the Everglades park south of Naples.
Wildlife workers had planned to try using noises such as banging on pipes and revving boat engines to herd the whales out to the open ocean. But that turned out to be unnecessary, and the workers simply used positioning of the boats to prevent any of the whales from turning away from the open sea, Mase said.
Teams from NOAA, the National Park Service, the Coast Guard and state wildlife agencies were working to prevent any more whales from stranding. The animals had not been cooperating Wednesday, when most were in about 3 feet of water.
The short-finned pilot whale is known for its close-knit social groups: If one whale gets stuck or stays behind, the others are likely to stay or even beach themselves as well. Pilots are among the smaller of the whale species, with adult males reaching up to 18 feet in length and females 12 feet.
The species is also the one most commonly involved in mass strandings. According to NOAA, there was a stranding of 23 pilot whales at Ft. Pierce, Fla., in September 2012 and one involving another 23 whales at Cudjoe Key, Fla., in May 2011. The last one in the Everglades area was in 1995.
Federal officials were notified about the whales Tuesday around 4 p.m. Because of the remote location, workers were unable to access the site before dark. They arrived Wednesday morning and discovered 45 whales still alive.
"There were some that were very compromised and in very poor condition," Mase said.
Federal officials euthanized four whales Wednesday, but no more were put down Thursday.
Mase confirmed Thursday that sharks had begun to feed on the dead whales. Necropsies were completed Thursday, and scientists will look for disease or other signs to indicate how whales got stuck in the shallow Everglades waters.
"It may take weeks and weeks and even months to get those results back," she said.
Associated Press writer Curt Anderson in Miami contributed to this story.
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