More than 80 false killer whales have been found lifeless after a mass stranding along the remote coast of Southwest Florida in Everglades, the National Oceanic and Atmospheric Administration (NOAA) has reported.
The death toll reported last Monday was 81, with one of the rare whales discovered alive. Rescue crews continued searching for more as the pod in the biggest recorded stranding of such whales in the state was originally believed to be about 100.
“[The whales] were deeply embedded in some of the mangrove making response efforts extremely difficult,” said stranding network coordinator Blair Mase.
Biggest Mass Stranding In The State
The first report of the incident near Hog Key, which sits in the middle of islands off Southwest Florida, was received last Saturday. The U.S. Coast Guard confirmed the mass stranding and a team from NOAA and the state Fish and Wildlife Conservation Commission then rushed to the scene, which was around an hour of boat ride from the shore.
They attempted to herd some of the affected whales to deeper water Saturday night and Sunday, but efforts were hampered by shallow muddy flats as well as the mangrove-laden shoreline.
Calves and juvenile and adult whales alike were entangled in the mangroves, while lack of cellphone coverage and the threat of sharks also affected the efforts, Mase added.
The team had to euthanize nine of the sick whales, while another 72 of them died Sunday.
Why Whales Become Stranded
There is not a lot known about false killer whales, the fourth biggest member of the dolphin family and usually live in warm and deep waters in the oceans. They resemble orcas from a distance but lack the notable white oval encircling the eye of their larger kin.
Insufficient data keep the total number of false killer whales worldwide unknown, according to the IUCN Red List. A 2004 study of the organization, however, pegged pods in the northern Gulf of Mexico at 1,038.
NOAA studied samples from the dead dolphins to determine why the animals swam ashore, completing full necropsies on six whales and partial dissections on others. They are looking at different possibilities, from unusual weather and changes in tide to military sonar exercises.
Months before, a federal court ruled against low-frequency sonar testing by the U.S. Navy as it was seen to affect dolphins and other marine creatures relying on the sound generation.
Strandings of this species have previously occurred, the largest one happening in 1946 when about 835 whales were stranded near a beach in Argentina. While they tend to swim in pods of only about 10 to 20, the whales typically die en masse during strandings.
In 2013 in northeastern Brazil, 30 dolphins beached themselves in shallow sands and biologists remained uncertain as to what caused the unfortunate situation: either the pod leader was hurt, or the dolphins were trailing a school of fish when they fell trap to the high sand banks in the area.
Large strandings have taken place in South America and Australia but rarely in the United States, its last one in 1986 when a 40-strong pod swam near Florida’s Cedar Key.