13 minute read
The Spinning Fish Crisis
BY ALEXANDRA MARVAR
More than 50 species of fish. Sharks. Shorebirds. Beginning in fall of 2023, Florida’s coastal species have been stricken by a mysterious and sometimes fatal neurotoxin. Here’s what happened when scientists, state agencies, guides and anglers carried out a widespread, coordinated response.
On a blustery winter night in December, Allison Delashmit boarded a boat with team members from Bonefish & Tarpon Trust and the Florida Keys Fishing Guides Association.
“It was around nine o’clock. It was raining outside, and really cold. And we went out to try to see these fish acting oddly,” she said. “Multiple other people had reported seeing them doing weird things that day in a culvert here in the Lower Keys.”
Delashmit had only just recently stepped into her role as the Executive Director of the Lower Keys Guides Association (LKGA). She had a mind for marketing and bringing people together, but it was her husband who was the fishing guide. She hadn’t yet seen this weird behavior—fish twirling and breaching erratically—which BTT’s Dr. Ross Boucek had been tracking for weeks as it swept Keys baitfish populations, but that was about to change.
“We’re all standing there soaking wet, with a net, trying to catch some of these mullet that were acting bizarre, and Ross was taking samples. And I remember thinking, as I’m standing there, soaking wet and freezing: ‘What am I doing? Here I am sitting on the side of the road at midnight with fish that are spinning—and drawing blood from them.”
Delashmit wasn’t the only Keys resident who found herself abruptly inducted into the wild world of citizen science over the past eight months. Since October, reports had been rolling in. Boucek’s phone had been ringing off the hook. The Florida Fish and Wildlife Conservation Commission’s Fish Kill Hotline was getting these strange calls, too: Wildlife was spinning out in Big Pine Channel. Off Little Torch Key. At Cudjoe Gardens Marina. It started with baitfish. Then, bigger fish. Sharks. Even pelicans.
The issue drew national attention when word spread about the dozens of critically endangered smalltooth sawfish dying off. The FWC tallied 53 sawfish dead between the start of the event and mid-June, a staggering number considering there may be as few as hundreds of the U.S. population still left in the wild. For Delashmit, Boucek, and the dozens of Keys locals who’d been watching this situation build, it was time to gather data, and get the country’s top fish experts on the line.
The Mystery Of The Spinning Fish
According to BTT Vice President for Conservation and Public Policy Kellie Ralston, by January, the BTT team felt they had enough reports of spinning fish in the Keys to make a grave determination: “We started to get the feeling that this was something different—that this was bigger and potentially longer lasting than any issues we’ve seen in the past,” Ralston recalled.
“We certainly had significant red tide events in recent years, as well as blue-green algal blooms around the state, that have caused concern… but nothing to this extent.”
It would take months of data collection and analysis to home in on what was causing this “spinning fish” phenomenon, and that was essential before any steps could be taken to stop it.
The good news? Stakeholders had a serious head start. BTT— alongside LKGA, which launched their report survey not long after that fateful rainy boat ride—stepped right into full crisis response, delivering all the report data to date to a coalition of scientists and state agencies including Florida International University, University of South Alabama, Florida Gulf Coast University, FWC, and the Florida Department of Environmental Protection.
From January onward, dozens of collaborative research missions were carried out, gathering more than 300 fish samples, and even more water samples, to have scientists test for more than 250 chemicals and natural toxins.
“Whatever this is, it does not discriminate based on species size, migratory pathways or behavior,” Boucek reported in the second of two livestreamed dispatches from leading scientists on the effort, broadcast on Facebook Live in May. “It’s indiscriminate across multiple species—basically, everything that swims in the water with gills has been affected to some degree.”
Environmental toxicologist Dr. Alison Robertson, a professor at the University of South Alabama and a senior marine scientist at the Dauphin Island Sea Lab, was among the scientists leading the charge. From the moment she got involved, she said, her lab team was at work seven days a week performing thousands of analyses of algae, seawater and fish tissue, and finding evidence of toxins both familiar and unfamiliar to the Florida Keys.
“When fish are affected by anything neurological, they do this sort of thing: loss of equilibrium, swimming upside down, breaching vertically in the water column, having impaired gill movement,” Robertson said.
There are a number of things that can produce these types of neurotoxins, from pollutants to parasites. Environmental changes like too little oxygen or too high a water temperature could cause effects like this as well. But this event was nothing like anything the scientists had seen here before.
“We’ve seen fish behaving weirdly through time in different places, but maybe not for this long,” Robertson added. “The duration and the geographical spread of the event is unique.”
The coalition launched investigations into four lines of inquiry, which Boucek and scientists Robertson, marine ecologist and algal bloom expert Dr. Michael Parsons at Florida Gulf Coast University, and others reported on during the two Facebook Live broadcasts. Those four leading theories under investigation were 1) potential contamination from human-generated sources, like wastewater effluent or pesticides; 2) evidence of degrading fish health metrics from, for example, pathogens or parasites; 3) contaminants in the water column, like red tide; or 4) contaminants from the sea floor.
What they found required work to sprawl far outside the lab.
All Hands On Deck
There were some 50 researchers involved in the response. But on the water every day, there were the guides. Approximately 70 guides from both the inshore and offshore fleets across the Keys were the effort’s indispensable “eyes on the water,” as Boucek puts it.
It was Keys fishing guides who filed the earliest reports of the phenomenon. But they weren’t just the canaries in the coalmine for early detection—they stayed with the effort the entire way, guiding research missions, and collecting valuable samples themselves.
As the research effort unfolded, Delashmit recalled, “the fishing guides continued to say, ‘We want to help. We feel like we can help—and we are not scientists, we can’t do the science, but we do have boats, so we can take the scientists out.’”
To help facilitate this, LKGA launched what Delashmit called the Guide Rapid Response Network. “Guides that are in our association can apply to be in this network,” she said, “submitting an application form and a W9, so we can pay them officially, with grant money.”
This “lateral partnership between the fishing community and the scientists,” as Boucek put it, is something both BTT and the LKGA had been working toward for years. While the circumstances were dire, stakeholders were buoyed with hope seeing it in action.
By the start of May, the LKGA had 10 guides signed on to the rapid response network. “Anytime there’s a need,” Delashmit said, “If Ross calls and says, ‘I need to go out and I need to catch fish, and we’re going to do a recovery study’—they’re at the ready.”
Boucek said the system was nothing short of a revelation: “Once we started doing it, I’m thinking, my god, this is just so much easier and makes so much more sense. Why is this not the common practice?”
Paying guides for their time to support science can help conserve and stretch grant funding, he explained: There are fewer up-front costs than a research institution would have because their boats are already operational and on the water, not to mention more suited to the environs and to the project of catching fish to gather tissue samples.
Plus, Boucek noted, there are the benefits of guides’ invaluable local knowledge, and the knowledge exchange when guides and scientists are working in tandem: “Science literacy for stakeholders or fishers, and ecological literacy for a scientist that’s behind a computer all day.”
It’s a partnership LKGA and BTT hope to keep in play. To help ensure that, Boucek is writing water quality grant applications, the funds from which would go entirely to supporting guides’ field capacity when they assist with things like rapid response and water quality assessments.
“We each bring different knowledge to the table,” he said. “And when you develop a system like we’re developing that merges both, it becomes an extremely powerful tool.”
Zeroing In On The Culprit
The crisis response led to the launch of infrastructure to support these progressive ways for guides and scientists to work together. It also led to some answers.
Some six months into this collaborative quest for answers, a prime suspect surfaced: a bottom-dwelling algae called Gambierdiscus, named for the Gambier islands of French Polynesia.
One red flag, according to Parsons: A liter of water from the Florida Keys typically contains just a few dozen Gambierdiscus cells. Samples gathered from spinning fish hotspots had more like 1,000 such cells—as much as 30X higher than what Parsons and colleagues have seen over the past decade.
“The higher-than-normal water temperatures that we saw down in the Keys [in the summer of 2023] could have perturbed the system in such a way that Gambierdiscus is now at an advantage,” Parsons said in a BTT Facebook Live broadcast.
But, according to Parsons, Gambierdiscus numbers tend to peak in colder weather, and drop in the heat of summer.
In line with his predictions, reports of erratic fish behavior did drop off as summer of 2024 set in.
“Going through some of the data,” Boucek said, “what we saw is we had a pretty abrupt warm-up at the beginning of March, and right coinciding with that warm-up, we had loads of new reports coming in. Symptoms got way worse for some fish that were pretty resistant to it. And that maintained pretty consistently until we had a second warm-up around mid-May.” Then, when the water hit a certain temperature this summer, reports suddenly dropped off, “suggesting whatever this is has a very narrow temperature tolerance,” he said, “which does match the Gambierdiscus hypothesis quite well.”
WHAT’S NEXT FOR SPINNING FISH?
So, what will happen this fall when temperatures drop again? Will reports of spinning fish surge? That, the BTT team says, is the $2 million question.
“It could come back. The conventional lines of wisdom would say it should,” Boucek said. “But you know, the other element to this is when you have something that’s so extremely unusual, to the tune that no one’s ever seen this in the world like ever, what is the likelihood that becomes a ‘new normal’?”
Large-scale grants from the Florida Department of Environmental Protection and the American Sportfishing Association, along with significant funding from several private donors, were instrumental in the urgent, initial response from the start of the reports through the summer of 2024, Ralston said. Seeing just how much progress the coalition was able to make with those funds, state legislators opted to appropriate another $2 million to the effort for the 2024-25 budget year.
“The challenge is, certainly, that science does not necessarily give you a specific answer in a specific timeframe,” Ralston said. “My hope is that we’ll see at least a temporary decline [this summer], and hopefully, a permanent decline [overall]. But, we need to understand what happened now, so that we can be better poised to address needs in the future.”
Boucek says next steps will be a balance between 1) bringing experts from around the world to get diverse opinions on the data collected to use this event as a case study moving forward; and 2) being prepared, just in case, for a “round two.”
“It just goes back to our perception of ecosystems and habitats,” Boucek said. “We think they’re going to degrade slowly, and this progression of degradation is going to be something that’s obvious, and visible, and proportional over time—like we should see, like, X loss of seagrass every year, or the water getting a little worse every year.”
In reality, though, ecological changes can happen in a flash: In Florida Bay in 1987, 60,000 acres of seagrass died overnight. In 2011, a cold weather event killed 40% of Florida’s boulder corals. This year, a significant percentage of the last remaining U.S. sawfish population was wiped out. “Things are fine until they’re not,” Boucek said. “So, the more comfortable we get when things are fine, the more we’re setting ourselves up for big problems when all of a sudden, that light switch turns on, that next heat wave comes.”
“I hope we come out of the back end of this and just know that we need to be so much more proactive about finding where we’re stressing systems out and fixing those things, so when the insult comes, the system can absorb it,” Boucek said. “We need to get out of this mindset that we can be reactive. Just because the water’s clear and everything looks good doesn’t mean it is.”
Alexandra Marvar is a freelance journalist based in Savannah, Georgia. Her writing can be found in The New York Times, National Geographic, Smithsonian Magazine and elsewhere.
WHAT CAN YOU DO?
Consider the fish. Don’t shine flashlights into the water, as this can distress fish that are already compromised and sensitive. It’s been found to incite erratic behavior in fish that are behaving normally.
Report, report, report. If you see strange fish behavior, add your sighting to the growing database helping scientists better understand this issue. Report to the LKGA or the FWC’s Fish Kill Hotline: 1-800-636-0511
Support ongoing research. This scientific study would be impossible without funding. Your donations to BTT and other organizations leading this research are an essential part of scientists’ search for causes and solutions.
Make your voice heard. Join the fight to protect and restore our water quality, so Florida’s water coastal and marine habitats are healthy enough to prevent or bounce back from events like this one. Learn more at: BTT.org/winbackourwater
Find the latest updates at BTT.org/Spinning-Fish.
