Hundreds of coastal sharks shelter in Florida canals to avoid toxic red tide

The red tide outbreak has been an issue on the coast of Florida since 2017

Longboat Key residents in Florida have new neighbors - bonnethead, blacktip, nurse, and lemon sharks.

Hundreds of sharks are leaving the coastline and have taken up home in the Florida canal, and environmental experts say it is to escape the impacts of a toxic red tide.

Red tide occurs when there are too many algae (Karenia brevis) in the water which pollute the surrounding area with harmful toxins, according to the Florida Fish and Wildlife Conservation Commission (FWC).

“You just don’t normally see sharks piling up like that in these canals, they do go in there but not in the huge numbers that we’re seeing reported,” Michael Heithaus, a shark expert and biological sciences professor at Florida International University, told The Guardian.

The red tide outbreak has been an issue on the coast of Florida since 2017. The bloom started on the southwest coast and spread to the panhandle and east coast, causing 2,000 tons of dead marine life.

This year’s bloom may be caused by both warming waters and pollution. In April, the Piney Point fertilizer plant released more than 200 million gallons of toxic discharge into Tampa Bay. Experts told Audubon, an environmental non-profit, that the waste contributed to the severity of the bloom.

The climate crisis has caused the surface of the ocean to warm about one degree over the last century, which is linked to an increase in algal blooms.

The polluted water can cause respiratory issues in humans and has killed droves of fish, dolphins, turtles, and manatees.

Last month the National Weather Service issued a warning for Pinellas County residents, saying the red tide bloom may cause coughing, sneezing, and watery eyes. Those with asthma or a lung condition are particularly susceptible.

The harmful toxins have also already caused a record number of manatee deaths this year, and this past week alone, it’s killed fish in nine counties and caused respiratory issues for people in five counties, a FWC report said.

Florida Governor Ron DeSantis started The Harmful Algal Bloom Task Force to coordinate with other research groups on how lessen the severity of red tides.