Authorities said eight pilot whales have died in shallow waters off Florida's southwest coast. Six others remain unaccounted for.
The Coast Guard temporarily closed the area to traffic and ordered boaters to reduce speeds Tuesday as they searched for the other whales.
On Monday, two whales died and two others were euthanized after beaching themselves near Fort Myers.
Officials said necropsies will be performed on the dead whales to find out whether they were sick.
In December, more than 50 pilot whales stranded in Everglades National Park. Several died.
Pilot whales live in deep water and swim inland if they suffer from toxicity or disease. They tend to travel in pods of a couple dozen or more and tend to follow one or two pod leaders, or navigators.
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