KEY WEST, Fla. – It’s a somber anniversary in the Florida Keys. This time last year, residents and tourists began witnessing the bizarre behavior of fish spinning disoriented and acting distressed.
The phenomenon impacted more than 80 species of fish and rays and stunned onlookers and social media users. But it was the critically endangered smalltooth sawfish that suffered the biggest loss. At least 54 were reported dead by Florida Fish and Wildlife Conservation Commission from Key West, north to the Saint Lucie River, to even as far as Tampa Bay.
Their numbers are now only believed to be in the hundreds. While the catastrophic event subsided in the summer, the mission to find out what sparked this event has not slowed down.
“The mortalities of this sawfish is unprecedented and very concerning, because it’s an endangered species, and approximately 10% of their population has died during this event,” explained Michael Parsons, a professor of marine Science and the director of the Vester Field station at Florida Gulf Coast University.
The algal bloom expert leads the research team that has been collaborating with FWC and the local fishing guides since the onset.
Right now all of the science has pointed to a conspicuous suspect.
“All the evidence points to gambierdiscus being part of this,” Parsons said.
Gambierdiscus is a benthic toxic microalgae that lives on seagrasses and larger algae. It’s always been present in the marine environment here, but it’s usually on the bottom – rarely in the water column and never in such alarming abundance.
“Typically, we see maybe 30 cells per liter of water…that’s a low amount,” Parsons explained. “And we were seeing 5,000 (to) 10,000 cells per liter, which is more than anyone ever reported previously.”
Still, scientists insist this is not the only ingredient in this toxic soup.
“Pesticides, and herbicides, and pharmaceuticals, and all sorts of things…so there’s a lot of partners that are looking at all of those angles to see if they could also be contributing,” emphasized Alison Robertson, marine toxicology expert and associate professor of marine cciences at the University of South Alabama.
The good news is that since the summer, the levels of gambierdiscus have been back down to normal. That’s because the toxic microalgae doesn’t thrive in warm waters.
But now that winter is here and waters have begun to cool back down, scientists and wildlife experts are bracing for impact.
“We were totally taken off guard last year by the magnitude and the breadth of this, and this year we’ve got a team put together, and we’re ready to respond,” underscored Thomas Matthews, the FWC program administrator and director of the agency’s regional lab in Marathon.
The team from the research lab was the first on the scene when the event started taking place, and now FWC has beefed up reinforcements.
“The legislature has given us (FWC) a couple million dollars that we’ve spread around, and we are ready to go to understand both from a chemical point of view and those researchers, and a fish health point of view,” explained Matthews. “We actually have people who do necropsies to understand the diseases and the reasons fish die.”
Meantime, also on the water, Sawfish expert Dean Grubbs and his team from Florida State University were back in the Lower Keys tagging and sampling to see how significant the hit was to the population.
“I went down there last week expecting we would that we wouldn’t catch very much…and, you know, we caught and tagged 11 big sawfish,” said Grubbs. “And so I’m just very excited about that.”
“So that leaves you with hope?” asked Local 10′s environmental advocate Louis Aguirre.
“Yeah exactly, they all seem to be healthy,” Grubbs responded. “We predict this will be something that probably will recur, but hopefully it doesn’t recur at with the severity that it that happened last year.”
Grubbs will leave one team member stationed in the Keys all winter should the event spark back up. Efforts to save the one distressed sawfish that was rescued last April were unsuccessful and the fish had to be euthanized.
With lessons learned, all stakeholders say they are better prepared for whatever happens next.
“All we’re equipped to do right now is to respond to it,” said Grubbs. “So the next steps, obviously, is to figure out what caused it so that we can hopefully figure out some sort of ways to mitigate this from happening in the future.”
Scientists believe the fish became exposed to the toxins through their gills and not through consuming other infected fish. This is why, so far, no humans have shown signs of getting sick.
All seems quiet in the Florida Keys for now, but if you see any signs of fish acting bizarre or in distress, contact FWC using the information below.
HOW YOU CAN HELP
Report sightings of healthy, sick, injured or dead sawfish to FWC’s Sawfish Hotline. Include date, time and location of the encounter, estimated length, water depth and any other relevant details.
- 1-844-4SAWFISH (1-844-472-9347)
Report sightings of abnormal fish behavior, fish disease, or fish kills to FWC’s Fish Kill Hotline.
- Submit a fish kill report
- Call 800-636-0511