NORTH HUTCHINSON ISLAND — They swam to the beach two weeks ago, far from their deep ocean home, where they see with sound and live in close-knit groups of 25 to 50 animals that feed by forming half-mile-long skirmish lines to herd squid.
Twenty-two short-finned pilot whales beached themselves Sept. 1 on North Hutchinson Island in what seemed, to humans, like mass suicide. No one is sure why pilot whales do it.
Five smaller whales survived the mass strandings, when a small army of veterinarians and volunteers rescued them and comforted the others as they died.
The five juveniles of a few hundred pounds each — adult animals can reach 24 feet and 7,000 pounds — were taken a short distance to Harbor Branch Oceanographic Institute at Florida Atlantic University in Fort Pierce. There, they swam in a saltwater pool while veterinarians stabilized their health.
One died, and the surviving two males and two females were taken Sept. 5 to SeaWorld Orlando. They remained in stable condition Friday and are continuing to receive round-the-clock care from the park's veterinarians and staff, said Mari Delgado, SeaWorld Orlando's associate manager for marketing.
"The whales remain in a quarantine rehabilitation area and cannot be seen by the public," Delgado said.
There are at least three instances when wild pilot whales have been returned to the Atlantic Ocean — two of them in Florida. It's too soon to tell if any of the North Hutchinson Island whales can be released, said Blair Mase-Guthrie, stranding coordinator for a region covering eight southeastern states, Puerto Rico and the U.S. Virgin Islands.
"Once we feel the whales are stable and out of the woods, medically speaking, that will be determined by an outside panel," she said.
That panel will be formed of eight to 10 biologists who have no connection to either SeaWorld or the National Oceanographic and Atmospheric Administration, said Mase-Guthrie, who works for NOAA.
Roy Crabtree, NOAA's Fisheries Service southeast regional administrator, will have the final say on whether the pilot whales are released or kept in permanent care at one of 32 facilities approved for marine mammal care. He seldom strays from the outside panel's recommendations, Mase-Guthrie added.
SeaWorld Orlando's marine mammal experts also are caring for two female pilot whales rescued from a May 2011 stranding on Kudjoe Key. They have been deemed non-releasable by a panel of biologists: One has a curved spine and remains in a rehabilitation area outside public view.
The other, named Freddie, lives is SeaWorld's whale and dolphin stadium, but is unseen for now by the general public. Freddie was too young to have learned how to survive in the open sea before stranding herself.
Young pilot whales seem to absorb lessons in hunting and other survival skills through the social network of their pod.
"With many of the toothed whales, there is a lot of learning going on," said Alisa Schulman-Janiger, a volunteer biologist with the American Cetacean Society in San Jose, Calif. "They have very strong social bonds," she said. "A lot of it has to do with cognitive learning and passing that learning on."
For that very reason, the youngest of the four North Hutchinson Island pilot whales — a nursing calf — is not a candidate for release.
"She did not get the education that they need to survive," Mase-Guthrie said.
Thursday, scientists and other stranding network officials had a three-hour debriefing on the North Hutchinson Island event.
"We talked about what we did well and what we could do better the next time there is a mass beaching," Mase-Guthrie said.
Pilot whales are the marine mammals that most often strand themselves in Florida. They live far out to sea by nature and can't be readily observed, so much of what biologists know about them comes from necropsies. The bodies of the dead North Hutchinson Island pilot whales went to laboratories across the southeastern United States.
All those whales had empty stomachs and were malnourished, Mase-Guthrie said. Necropsies also showed that some of the whales had heavy infestations of marine parasites in their nasal cavities.
"That could affect their sonar capabilities," she said.
Scientists also are on the lookout for morbillivirus. The airborne pathogen is spread when whales exhale through their blowholes and infections can lead to death. The four surviving North Hutchinson Island pilot whales tested negative for morbillivirus, Mase-Guthrie said.
The American Cetacean Society is opposed to new capture of healthy toothed whales from the wild for the sole purpose of permanent captivity, said Kathy Zagzebski, its president. The 1972 Marine Mammal Protection Act has stopped capture in the United States, but whale hunts still take place elsewhere in the world.
"Stranded animals provide a different scenario," Zagzebski said. "One of the goals of the national marine mammal health and stranding response program and its federally
"Sometimes, for medical or behavioral reasons, an animal cannot be released because it would pose a danger to the wild population and/or to itself," she added. "In these instances, stranding network organizations are faced with the decision to euthanize the animal or place it into a federally licensed captive facility."
Pilot whales are very attached to their own social groups. These are made up of about eight females to every male, with bachelors generally leaving their birth school and females remaining for life, according to NOAA information.
Many scientists believe the whales strand when a strong group leader gets sick and the rest follow it ashore.
"If there's a dead whale or a stranded whale on the beach, they just keep coming back to the beach," Mase-Guthrie said. "Something radical that's been tried in New Zealand is that they actually kill the leader."
Schulman-Janiger works mostly with Pacific Ocean killer whales which, unlike pilot whales, have been successfully bred in captivity.
"There's a big movement to try to get whales on display released again," she said.
Pilot whale releases
A pilot whale, the largest member of the dolphin group, is the whale that most often strands itself in Florida and the eastern Atlantic seaboard. Pilot whales have been nursed back to health and released on at least three occasions.
December 1986: Three calves surviving from a pod of 27 stranded on Cape Cod are rehabilitated by the New England Aquarium in Boston. Six months later they were released into the ocean with satellite tags and appeared to have joined another pod.
April 2003: Twenty-eight pilot whales strand off Big Pine Key in the lower Florida Keys. Seven were rehabilitated at the Marine Mammal Conservancy in Key Largo and released. At least four of them were seen in a wild pod, but one strayed and was eaten by sharks off the coast of Jupiter.
May 2011: Twenty-three pilot whales stranded in shallow water off Cudjoe Key in the lower Florida Keys. Rescuers were able to immediately release two out into the Gulf Stream. Two other animals, non-releasable for medical and behavioral reasons, are under the permanent care of SeaWorld Orlando.
Releasing pilot whales can be expensive and involve air/sea operations: first, to locate a wild group into which to introduce rehabilitated whales, then tracking their progress through satellite tags.
Most money for these efforts come from private donations and grants. There is very limited federal funding available.
Sources: NOAA Fisheries Service, St. Petersburg; the American Cetacean Society.