Mysterious Illness Affects Smalltooth Sawfish in Florida Waters
ST. PETERSBURG, Fla. (AP) — Florida wildlife officials report a disturbing resurgence of a perplexing condition impacting the smalltooth sawfish, an endangered species indigenous to the region. Last year alone, there were over 50 recorded fatalities as a result of this affliction, which causes these fish to exhibit erratic spinning behaviors in the water.
Recent Trends and Reports
Since December 2023, wildlife agencies have documented 22 instances of sawfish displaying abnormal spinning behaviors in the Florida Keys. Of these reports, six have resulted in confirmed deaths, signaling a troubling revival of the condition after a roughly nine-month hiatus.
Investigation and Findings
Despite rigorous testing by the Florida Fish and Wildlife Conservation Commission (FWC), including examinations for parasites, bacteria, viruses, and over 250 different chemical agents, officials have yet to determine a definitive cause for the phenomenon. The FWC noted subtle changes were observed in the brain tissue of some affected sawfish, indicating the need for further investigation.
Species Background
The smalltooth sawfish, closely related to rays, skates, and sharks, is recognized by its distinctive elongated snout, which bears rows of sharp teeth. These prehistoric fish can grow up to 17 feet (approximately 5 meters) in length and have inhabited oceans for millions of years. Once plentiful along the southeastern U.S. coast, their numbers have dwindled significantly, now primarily found in regions of southwestern Florida and the Florida Keys due to habitat loss.
State Response
In light of the latest mortality instances, Florida state legislators allocated $2 million to facilitate an investigation into these mysterious sawfish deaths, particularly in Biscayne Bay, Florida Bay, and the Florida Keys. Part of this funding is directed toward collaborating with local fishing guides to carry out water sampling and other investigatory measures. Additionally, the FWC has established a hotline for reporting instances of spinning or erratically moving sawfish.
Potential Environmental Factors
One hypothesis suggests that a prolonged heatwave last year—effectively attributed to climate change—may have altered the composition of algal blooms in the ocean, specifically at the sea floor where sawfish tend to frequent. Notably, sawfish, like rays, draw water through gills located on their undersides, which could be impacted by changes in bottom-dwelling algae. The FWC has identified various algal toxins present in the tissues of affected fish, which are currently under examination as potential causative agents.
The Threatened Status of Sawfish
Listed as an endangered species in the U.S. since 2003, the smalltooth sawfish is legally protected in Florida, where it is prohibited to capture, harm, or harass these fish.
Broader Ecological Context
The plight of the smalltooth sawfish highlights ongoing environmental challenges in Florida. In recent years, the state has witnessed significant die-offs of other protected species, like the manatee, which suffered from severe declines in seagrass habitats due to pollution. In response, state and federal efforts included feeding manatees with lettuce near a power plant, which contributed to a measured recovery, with 565 manatee deaths reported in 2024 compared to a peak of 1,100 in 2021.
As investigations into the cause of the smalltooth sawfish deaths continue, Florida faces mounting pressure to address the health of its marine ecosystems and the species that inhabit them.
