ST. PETERSBURG, Fla. — Endangered smalltooth sawfish, marine creatures virtually unchanged for millions of years, are exhibiting erratic spinning behavior and dying in unusual numbers in Florida waters. Federal and state wildlife agencies are beginning an effort to rescue and rehabilitate sawfish to find out why.
The National Oceanic and Atmospheric Administration announced what it calls an “emergency response” focused on the Florida Keys starting next week. A NOAA news release called the effort unprecedented.
“If the opportunity presents itself, this would be the first attempt ever to rescue and rehabilitate smalltooth sawfish from the wild,” said Adam Brame, NOAA Fisheries’ sawfish recovery coordinator.
Sawfish, related to rays, skates and sharks, are named for their elongated, flat snout that contains a row of teeth on each side. They can live for decades and grow quite large, some as long as 16 feet (about 5 meters). They were once found all along the Gulf of Mexico and southern Atlantic coasts in the U.S., but now are mainly in southwestern Florida and the Keys island chain as their habitats shrink. A related species is found off Australia.
Since late January, state wildlife officials have been documenting what they call an “unusual mortality event” that has affected about 109 sawfish and killed at least 28 of them. There have been reports of abnormal behavior, such as the fish seen spinning or whirling in the water. Other species of fish also appear to have been affected.
“We suspect that total mortalities are greater, since sawfish are negatively buoyant and thus unlikely to float after death,” Brame said.
Officials haven't isolated a cause. The Florida Fish and Wildlife Conservation Commission reported Wednesday that sawfish necropsies have not revealed any pathogen or bacterial infections, nor problems with low water oxygen levels or contaminants such as chemicals, or toxic red tide. Water testing is continuing.
It's also not clear if the deaths and odd behaviors are related to a lengthy summer heat wave in Florida waters experts say was driven by climate change. The superheated waters caused other marine damage, such a coral bleaching and deaths of other ocean species.
The wildlife agencies are working with three organizations that will rehabilitate sawfish that are rescued. One of them, Mote Marine Laboratory and Aquarium, said in a news release that even relatively small numbers of sawfish deaths could have a major impact on the population, listed as endangered since 2003.
“We have quarantine facilities ready to accommodate rescued sawfish where they would be under observation by qualified personnel under specific care and release guidelines," said Kathryn Flowers, Mote Postdoctoral Research Fellow and lead scientist on the sawfish issue. "Attempts to solve this mystery call for robust collaboration.”
Brame said the effort depends on tips and sightings from the public of dead or distressed sawfish so rescuers know where to look for them. NOAA has a tipline at 844-4-Sawfish and FWC has an email, sawfish@fwc.com.
In recent years, threatened manatees also suffered a major die-off in Florida waters as pollution killed much of their seagrass food source. State and federal officials fed tons of lettuce to manatees that gathered in winter outside a power plant for two years, and the manatee numbers have rebounded some with 555 deaths recorded in 2023 compared with a record 1,100 in 2021.