Beached whales: How do you lead a whale to deeper water?

Wildlife workers will try again Thursday to lead 41 pilot whales out of dangerously shallow waters in Everglades National Park and back to the deep ocean waters where they belong.

The whales are stranded in a remote area near Highland Beach, the western boundary of Everglades National Park and about 20 miles east of where they normally live. It takes more than an hour to reach the spot from the nearest boat ramp and there is no cellphone service, complicating rescue efforts.

Of the 51 whales that ended up in the Everglades, six of the whales were found dead, and four of the whales had to be euthanized Wednesday, said Blair Mase, coordinator for the National Oceanic and Atmospheric Administration's marine mammal stranding network. At least three could be seen on the beach, out of the water.

Workers from the National Park Service and the National Oceanic and Atmospheric Administration spent all day Wednesday trying to herd the whales toward the ocean, but the marine mammals weren't cooperating.

The whales are stranded in a remote area near Highland Beach, the western boundary of Everglades National Park and about 20 miles east of where they normally live. It takes more than an hour to reach the spot from the nearest boat ramp and there is no cellphone service, complicating rescue efforts.

"We want to set the expectation low, because the challenges are very, very difficult," Mase said.

Park spokeswoman Linda Friar said rescuers Wednesday were trying to surround the whales, which were in roughly 3 feet of salt water about 75 feet from shore, and herd them back to sea.

"They are not cooperating," Friar said.

Workers also tried to nudge the whales out to sea earlier Wednesday with no success.

The short-finned pilot whales typically live in very deep water. Pilot whales, a member of the dolphin family (as are killer whales), are found throughout the world’s oceans, in both the northern and southern hemispheres, and are numerous in the Gulf of Mexico. The whales are highly social animals and tend to travel in pods of some 20 to 90 companions.

As The Christian Science Monitor reports, pilot whale beaching is common, for reasons that are still unclear but that could be related to social dynamics within the species' tight-knit pods, according to NOAA. In the largest pilot whale stranding ever reported, 450 pilot whales were trapped in a bay off of New Zealand’s Great Barrier Island in 1985. New Zealand and Tasmania have the bulk of all pilot whale stranding incidents worldwide.

The last mass stranding of pilot whales in southwest Florida was in 1995, according to NOAA.

Even if rescuers were able to begin nudging the 41 remaining whales out to sea, Mase said they would encounter a series of sandbars and patches of shallow water along the way.

This particular whale species is also known for its close-knit social groups, meaning if one whale gets stuck or stays behind, the others are likely to stay behind or even beach themselves as well.

"It would be very difficult for the whales to navigate out on their own," Mase said.

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.

Four were euthanized with sedatives, and more could be put down Thursday if their condition deteriorates, Mase said. She described the remaining whales as swimming and mobile but said scientists don't know how long they have been out of the deep, colder water they are accustomed to and could be impacted by secondary consequences, such as dehydration.

"I don't think we have a lot of time," Mase said.

Necropsies were being done Wednesday on the deceased whales. Scientists will look for disease or other signs to indicate how whales got stuck in the shallow Everglades waters.

As workers tried to coax the animals to deeper water, at least one could be seen a few feet from shore floating upside down with its head bobbing up and down. Three to four more could be seen on the beach bleeding.

Twenty-two pilot whales became stranded in Florida's Avalon State Park in Fort Pierce in 2012. Residents, state and national officials attempted to rescue them, but only five could be saved.

"It's not uncommon," Friar said. "But it's not something that happens a lot."

Mase said NOAA was consulting with experts in different counties with experience in herding whales to see if there were other options, but said she was not optimistic.

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Armario contributed to this report from Miami.

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