Dead fish showing up in the Destin harbor isn’t necessarily an unusual thing for one of the busiest fishing hubs in North America.
But after an unusually high number of dead Jack Crevalle fish began showing up in shallow waters of the harbor earlier this week, some anglers and wildlife officials are left wondering what is causing them to die in such large swaths.
On a cool Wednesday morning, at least 25 dead fish could be seen at or near the shoreline on the Holiday Isle side of the Destin harbor. Pelicans floated in the water nearby but didn’t seem interested in the dead fish closer to shore. Snowbirds took leisurely walks by condominium complexes close by but didn’t stop to take in the sight of the scaly mass graveyard.
The Jack Crevalles didn’t have any outward signs of trauma, as if they had been attacked by a larger fish or marine predator. They were lying on their sides, beady eyes wide open, frozen in time.
Patrick Meyers, a fisherman who was down on the docks across the harbor that morning, said he didn’t know exactly what was causing the fish to die, but did know what wasn’t.
“It’s not red tide, I definitely know that,” Meyers said.
Meyers, who said he’s been a fisherman in Destin for upwards of 30 years, said he has never seen anything like the mass fish kills he’s seen in the Choctawhatchee Bay recently. He suspects, however, that the recent cold snaps in the area might have contributed to their deaths.
“It’s not uncommon to see a dead fish here and there, like if they got hooked or something,” Meyers said. “But when you see them like they are now, something is happening to them.
“I don’t think they’re starving and I don’t think they’ve been poisoned or anything like that,” he added. “I think they’re just cold.”
Cold weather, colder fish
According to the Florida Fish and Wildlife Conservation Commission, Meyers is probably right. Since Jan. 1, when the first cold snap descended on Northwest Florida, eight separate fish kills in Okaloosa County have been reported to the FWC’s fish kill hotline, compared to one reported fish kill during the same time period in 2017. No fish kills were reported in November or December of 2017.
So far in 2018, the FWC’s fish kill hotline has logged 50 dead red snapper and pompano reported near the Louisinia Lagniappe restaurant on Destin’s Holiday Isle on Jan. 4, and 400 dead pinfish and “unidentified species” in Garnier Bayou in Fort Walton Beach on Jan. 10. Jack Crevalle fish, like the ones spotted this week in the Destin harbor, were reported in fish kills in Shalimar’s Poquito Bayou on Jan. 10, Fort Walton Beach’s Don’s Bayou on Jan. 12 and in a Holiday Isle canal in Destin on Jan. 20.
In Walton County, four fish kills have been reported since Jan. 1, including an incident where 2,000 mullet and unidentified species were found dead in the Choctawhatchee Bay near Point Washington.
Michelle Kerr, a spokeswoman for the FWC, said the agency has logged local fish kills involving red snapper, pompano, Jack Crevalle, bait fish, bass and perch. She said the number of fish kills reported this year is unusually high; statewide, the agency has received reports of 214 fish kills since Jan. 1, including the eight in Okaloosa County and four in Walton County.
Kerr said the quick drops in temperatures could trigger "cold stress" in the fish and also make them more susceptible to diseases.
Graham Northup, curator of fish and reptiles at the Gulfarium Marine Adventure Park on Okaloosa Island, said the last time he saw fish kills of a similar magnitude were in the winter of 2010. This winter, the Gulfarium has taken in several “cold stunned” sea turtles from Gulf of Mexico waters, and Northup believes the cold is affecting the fish in similar ways.
Extreme drops in the water temperatures, Northup said, can cause fish to have a sort of hypothermia that renders them unable to swim or eat, ultimately killing them.
“The fish here are not really set up like the northern species of fish, so these really quick drops in temperatures can affect them,” he said. “Their heart rate can drop, they get lethargic, their blood flow can decrease, they’re not eating as much. And a lot of these fish might eat vegetation that can die off in these cold weather events,” so some of them could be starving.
Northup said it was “hard to tell” if the fish kills would have an impact on the ecosystem.
According to the Choctawhatchee Bay Alliance, temperatures in the bay dipped into the low 40s during some of the recent cold snaps. A CBA spokesperson said staff was aware of the mass fish kills and would be collecting water samples to learn more.
A simpler explanation
Back on the Destin docks, the jury is still out among local fishermen as to the cause and effects of the mass fish kills. As Meyers, the fisherman, put it, “I’m in the business of killin’ fish, not wondering why they’re already dead.”
Jan Garcia, a first mate on the charter boat Unreel, said he wasn’t surprised when fish started turning up dead because some of the canals in the Destin harbor froze completely over during one of the cold snaps.
“If it gets cold around here, it usually starts happening in October, and that lets the fish know to get out of here and find warmer waters,” Garcia said. “But this year, the cold didn’t come until January, and the fish didn’t know to go. I think it took them by surprise. Some of them died, some of them didn’t.”
Clay Brunson, a lifelong Destin resident and former boat captain, said that at the end of the day, everybody has a different opinion as to why the fish die. He said he’s seen fish die when they get too close together in big schools and start restricting the oxygen in the water, and when fertilizer runoff from the local golf courses pollutes the harbor.
Either way, Brunson said sometimes fish just die, and nobody knows why.
“A lot of different people have opinions on what it is that kills the fish,” he said on the back of a boat he was working on Wednesday afternoon. “But sometimes, it’s as simple as the good Lord deciding it’s time for those fish to die.”