(USA TODAY) - The pod of pilot whales stranded in Florida's Everglades National Park has not been spotted today, a spokesperson for the National Ocean and Atmospheric Administration said.
An aerial team and a boat team were sent out today, but neither saw the whales, Allison Garrett said.
Garrett said there's hope that the whales have moved to deeper water, but it's possible they have all sunk to the bottom of the ocean.
"We just don't know where they are," she said.
As of 5 p.m., the whales had still not been spotted. Teams will not be sent out on Sunday.
"We will regroup if people see whales, but we are not going to send a team out tomorrow," Garrett said.
The whales began moving toward deeper waters Thursday, but 20 of the whales backtracked Friday.
The whales were about five nautical miles from the coast, a mile closer than Thursday. The development raised concerns that the whales could be sick or exhausted from the stranding.
Blair Mase, coordinator of the National Oceanic and Atmospheric Administration's marine mammal stranding network, said the animals appeared to be less organized and swimming slowly. Officials planned to call off the rescue mission if the whales stayed on their path Friday, she said.
The pod of 51 short-fin pilot whales became stranded Tuesday after swimming too close to the western tip of the park, Linda Friar, a spokesperson for the Everglades National Park, said.
Of the 51 whales initially stranded at Highland Beach, 11 are dead. Five that have not been located may have died and sunk to the ocean floor, Mase said.
Four dying whales were euthanized Wednesday when scientists determined they could not be saved. The carcasses were left in the water to decay naturally, she said. Six others died Wednesday.
The scientists hope examinations of the dead whales will yield clues to why they beached themselves. Mase said likely causes could be changing currents, changing water temperature or the Morbillivirus, which has infected more than 800 animals along the Mid-Atlantic and Southeastern coast.
The behavior of animals in mass strandings is unpredictable. Mase noted that a similar stranding occurred in the mid-1990s, when a group of beached whales re-stranded themselves after tentatively swimming back out to sea.
Short-fin pilot whales measure up to 20 feet. A tight-knit species, they often stay together as a group, and if one can't keep moving, they all stop.
Contributing: Associated Press
Emily Atteberry, USA TODAY