By Daniella Silva, NBC News
Wildlife rescue teams will continue their push to save the more than 40 pilot whales stranded in shallow waters off Florida's Gulf Coast on Thursday morning, according to park officials.
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Rescue efforts were set to resume at dawn on Thursday morning after being suspended by dark late Wednesday, said Linda Friar, spokesman for Everglades National Park. With the whales stranded since Tuesday, the ability of the teams to get the whales into deeper waters is critical to their survival.
"They need to be in deep water in order to feed. If we can’t get them out, they could begin to be starving themselves," Friar said.
It was unclear if any more whales had died overnight as the Coast Guard waited for morning light to assess the situation, Friar said. By Wednesday, six whales were found dead and four more had to be euthanized.
Staff at Everglades National Park and marine mammal specialists with the National Oceanic and Atmospheric Administration have been desperately working to move the whales after they were discovered on Tuesday afternoon by a fishing guide.
But the mission has faced many challenges. The whales are stranded in a remote area of the park near Highland Beach and are more than 20 miles from waters deep enough to support them. Friar said getting rescue teams to the whales was difficult and time consuming in itself, with the whales stranded in an area over 90 minutes away by boat from Flamingo, Fla., and an over an hour away from Everglades City.
Compounding the rescue efforts is the highly social nature of the whales.
"Part of the issue is that the animals are cohesive type of group," Friar added. "They're really resistant to leaving any members of their pod behind."
It's unknown why the whales ended up in such shallow waters, said said Liz Stratton, a marine biodiversity specialist and assistant coordinator of the Marine Mammal Stranding Network.
"Sometimes, whales strand because they are sick. Sometimes they strand because they run out of water [or because of] parasites or other problems," Stratton told NBC News on Wednesday.
Adding to the challenge: the possibility of sharks in the area.
Tissue samples from some of the whales were being collected and sent to a lab to help determine the cause of the breaching.
Mark Potter, M. Alex Johnson and Erika Angulo of NBC News contributed to this report.