Florida's toxic algae crisis: Are Gulf and freshwater seafood safe to eat?

Island Seafood Co. on Matlacha has been quiet.

Too quiet.

As a massive red tide bloom kills fish, dolphins and sea turtles in the Gulf of Mexico, with toxic blue-green algae choking inland waters, this usually popular seafood market and fish house has been equally dead. What few customers trickle in have the same question: Is the seafood safe?

“Is red tide affecting you guys? Does it affect these fish? We hear that from everyone,” Island Seafood’s owner Katie Fischer said.

“We’ve owned this for five years and this has been our worst month since we’ve owned it. Our goal has become to educate people, to let them know the seafood we’re bringing in and the seafood restaurants are serving is safe to eat.”

And it is. At least in those cases.

The overarching answer to the “Is the seafood safe?” question is, however, much more complex. Little is known about the impacts blue-green algae can have on freshwater fish and blue crabs, but early research doesn’t paint a promising picture.

In case you missed it:Water samplings shows red tide decreasing at Collier beaches

More:Particularly strong, long-lived red tide still enveloping region

More is known about the effects of red tide on seafood, but with each new fish kill that washes ashore the local appetite for seafood, even perfectly healthy seafood, diminishes.  

“No one wants to eat fish when there’s a million dead fish floating in your canal,” Fischer said. “Believe me, we get it. But those fish aren’t our fish, not even close.”

Locally caught seafood isn’t exactly local.

Roger Schmall bid farewell to the Kayden Nicole Wednesday.

His 75-foot St. Augustine Trawler left the docks of Trico Shrimp on Fort Myers Beach that morning for a 16-day shrimping trip that would take the crew south to the pristine waters of the Dry Tortugas and Key West.

Schmall isn’t captaining this excursion, but he knows the route well.

“Most of the boats are in Texas for the Texas season right now. A handful have stayed here and are fishing the Tortugas. They’re 100 miles south of here, at least, nowhere near the red tide,” Schmall said.

“You have more to worry about eating imported seafood than eating our shrimp.”

When the Kayden Nicole returns later this month, its shrimp will be unloaded at TriCo and then sold at its market, as well as to wholesalers and a few local restaurants and resorts, including Crave in south Fort Myers and Pink Shell on Fort Myers Beach.

Trico’s owner-operator Chris Gala said diners have nothing to fear eating Gulf shrimp right now.

“In our market, customers ask every day if it’s safe and we tell them, 100 percent, yes it is,” she said. 

"Still we're seeing a decline in sales because of red tide and what people don't understand about our work."

More:To protect sea turtle nests, three keys closed in Ten Thousand Islands Refuge

More:Water samplings shows red tide decreasing at Collier beaches

Shrimp boats aren’t the only vessels escaping to cleaner waters. Long-line fishermen are spending the extra fuel, as well.

Back at Island Seafood, Fischer said her three company-owned boats are currently fishing for grouper and snapper 80 to 100 miles offshore. According to reports from the Florida Fish and Wildlife Conservation Commission, or FWC, the red tide bloom extends 20 to 30 miles offshore.

To add insult to injury, grouper and snapper catches are miserably low this year across Florida. The lack of supply has sent the price of the fish skyrocketing. But with few customers, Island Seafood hasn’t been able to take advantage.

“I was on the East Coast and saw grouper selling for $38.95 a pound. Who can afford that?” Fischer said. “We’re at $20.95 a pound, just eating the cost of extra fuel to try and keep things affordable for locals.”

Can you eat fish caught during red tide?

Commercial fishermen have the ability to escape from red-tide waters. But what about local anglers? Can they eat the fish they’re catching?

The FWC says a cautionary yes.

“(I)t is safe to eat local finfish as long as the fish are filleted before eaten,” a blurb under the Red Tide FAQ section of myfwc.com reads.

“Although toxins may accumulate in the guts of fish, these areas are disposed of when the fish are filleted. However, it is never a good idea to eat dead or distressed animals, especially in a red tide area.”

Shellfish such as clams, scallops and oysters from red tide areas should not be eaten.

Since those bivalves are filter feeders, taking in the algae-filled water and filtering it for nutrients, they can accumulate dangerous levels of toxins in their flesh. The FWC has halted the commercial and recreational harvest of shellfish in the southern parts of the Gulf through at least Sept. 30 due to red tide. Most commercially available Gulf oysters come from the northern edge of the Gulf, far from the current red-tide bloom. 

Rick Bartleson, a research scientist who studies the impact of red tide on marine life for the Sanibel Captiva Conservation Foundation, knows the dangers of red-tide contaminated shellfish well.

“I do know at least one person who was not aware of the closure and made the mistake of making an oyster stew using local oysters,” Bartleson said.

“He’s fine now, but he felt it.”

Bartleson said it can take months for red tide to flush out of bivalves. During past blooms, it took four months for local oysters to return to safe levels, “but the red tide wasn’t nearly this bad,” he said.

More:What travelers should know about Florida's red tide outbreak

Also:Particularly strong, long-lived red tide still enveloping region

Can you eat fish caught near blue-green algae?

With more than 1,000 square miles of Florida waters smothered by toxic, blue-green algae, it’s surprising how little is known about cyanobacteria’s effect on fish and blue crabs.

Despite scant empirical evidence, two of the nation's leading scientists working on the link between toxic algae and serious neurological diseases, said for them, eating a fish from waters bearing obvious cyanobacteria is simply too great a health risk. 

More:How is it affecting tourism and other businesses?

"I would not eat any fish caught in this area right now," Larry Brand, marine biology and ecology professor with University of Miami's Rosenstiel School of Marine and Atmospheric Science, said in an interview with Treasure Coast News last month.

Local health department officials also warn anglers and seafood lovers to use careful consideration before consuming fish caught near cyanobacteria.    

"Don't fish in or around a bloom, and don't eat any fish caught in or around a bloom," said Renay Rouse, spokeswoman for the Florida Department of Health in Martin County.

Unlike those red tide-afflicted oysters, which caused immediate sickness, cyanobacteria could present far more serious and long-term consequences.  

Brand and James Metcalf, a senior researcher with Brain Chemistry Labs in Jackson Hole, Wyoming, were in Stuart last month to participate in a panel discussion which followed a screening of the 2017 film, "Toxic Puzzle." The film chronicles the links between naturally occurring blooms of cyanobacteria and deadly neurological diseases such as Alzheimer's and Lou Gehrig's disease or ALS.

The link centers around an amino acid —  beta-Methylamino-L-alanine or BMAA. BMAA is found in cyanobacteria like the ones identified by the state Department of Environmental Protection in the waters of the Caloosahatchee, Lake Okeechobee, Blue Cypress Lake and St. Lucie River. In June and July, samples collected by the agency tested positive for microcystis aeruginosa or wesenbergii.

Some samples showed concentrations of microcystin well above what the World Health Organization considers safe for contact by mammals. 

"BMAA, a neurotoxin, was found in high levels in the brains of dead dolphins which were sampled," Brand said.

"(T)hey obviously got it from the fisheries. It indicates you got BMAA in your ecosystem."

That means commonly caught freshwater fish such as catfish and bluegill, and brackish saltwater fish such as snook, mullet and redfish may be contaminated with BMAA.

Brand said someone who eats contaminated fish may not experience disease symptoms for a decade or more.

"We’ve now shown the toxin can cause the plaques and tangles in the brain," Metcalf told Treasure Coast News.

"Now we’ve found a way to stop those plaques and tangles, so we’re already doing phase two human clinical trials on Alzheimer's and ALS patients. Based upon this research — if it's successful, and it may not be successful, we don’t know — but it also gives hope and help to people who are concerned about exposure to the algae blooms taking place here."

Crabs and other bottom-feeding crustaceans, per Metcalf and Brand, are of special concern. They tend to have even higher levels of BMAA.

"Shrimp and crabs, and more benthic-oriented fish, are on the bottom," Brand said. "Often, there a lot more cyanobacteria sitting on the bottom."

When asked if he would eat a crab caught in the Caloosahatchee right now, Brand's answer was clear: "No."

"We're struggling"

Jeff Haugland, owner of Island Crab Co. in St. James City, said business is down 75 percent from last summer. 

He said his crab boats avoid red tide and blue-green algae areas like the plague, not necessarily due to its impact on the crabs, but due to its impact on the fishermen.

"They're having trouble breathing. It's making their eyes water," Haugland said.

"They're not going to those areas."

A few miles east, back at Matlacha's Island Seafood, owner Katie Fischer has turned the market's sign into an educational tool. It reads: Still fresh still safe.

"We’re struggling and I can say that for every single fish house and restaurant on the island," Fischer said.

"It’s us, it's the captains, it's the hotels, it's the Realtors. Everyone's hurting. This is going to affect us for a very long time."

Staff writer Ed Killer of Treasure Coast News contributed reporting. Connect with this reporter: @ATometich (Twitter)