It’s almost the stuff of nightmares. Normally robust dolphins and gentle manatees are dying. Red tide has taken many victims.
Gruesome work resulting from the red tide outbreak continues at a fever pace at Mote Marine Laboratories, as scientist attempt to unravel how red tide kills marine mammals and other sea life.
Mote researchers confirmed Sept. 12 that 10 of 17 dead bottlenose dolphins recovered in the Gulf since July 1 were the result of red tide neurotoxins.
Mote completed necropsies on 10 dolphins, while samplings on the remaining seven dolphins had not been completed as of Sept. 17.
The National Oceanic and Atmospheric Administration had suspected red tide in the unusually high number of deceased dolphins found in the Gulf, but the tests were needed to confirm their suspicions.
Red tide, Karenia brevis, kills by producing a powerful neurotoxin that harms the central nervous systems of marine life, including fish, turtles, manatees and dolphins. Manatees suffer when eating contaminated seagrasses and all marine mammals breathe the contaminated air from the harmful algal bloom. Turtles and dolphins often eat fish compromised by the HAB.
The Florida Fish and Wildlife Conservation Commission has performed necropsies on dozens of dead manatees pulled from the Gulf and bay waters since the red tide began in October 2017.
Now Mote is teaming up with Florida International University in a new effort to help manatees exposed to red tide.
With a $428,000 grant from NOAA’s ECOHAB, the university and research lab scientists are working on a treatment protocol for exposed animals.
Mote immunology expert Cathy Walsh and FIU chemist Kathleen Rein are studying how a manatee’s immune system responds to certain antioxidants.
The scientists believe red tide exposure leads to oxidative stress, a harmful imbalance between free radicals and antioxidants.
Similar studies on treatments for human maladies have been underway for years. The current protocol for treating sickened marine mammals is the use of anti-inflammatories to aid in healing. Rein hopes a new treatment accelerates the process.
The FWC says as of Sept. 12, 115 manatees have died of red tide this year. By the end of August, 544 manatees had died in 2018. That number already exceeds the 2017 death toll of 538, and is roughly 8 percent of the state’s manatee population.