Continuing algae bloom brings another wave of dead fish to SW Fla. beaches and shorelines.
Dead fish are floating in Lee County waters and washing up on local shorelines again.
The first dead fish associated with a continuing red tide bloom in Southwest Florida were reported Nov. 25 in Estero Bay. Small numbers of dead fish have washed up sporadically since then, and this week, large numbers of dead fish were reported.
Since the bloom started, red tide has killed seven manatees in Lee County and two in Collier County; eight other manatee carcasses recovered in Lee are listed as suspect red tide victims.
“It must have been one big bloom,” said Tim Karas of South Fort Myers, who was stand-up paddle boarding Thursday near the Sanibel Causeway. “I can’t imagine. Today, I didn’t see any dolphins, sharks or manatees. It definitely had an effect on the rest of the wildlife. They must be smart enough to stay away from it.”
Red tide is a natural phenomenon caused by the single-cell alga Karenia brevis, which produces a powerful neurotoxin.
Under normal concentrations, less than 1,000 cells per liter of water, Karenia is not a problem.
But when Karenia undergoes a population explosion, or bloom, the increased toxin can kill fish and other marine organisms and render filter-feeding mollusks poisonous to humans.
It also can cause respiratory irritation in some humans.
Karenia concentrations of 10,000 to 100,000 are classified as “low” and can kill fish; concentrations of of 100,000 to 1 million are “medium,” and more than 1 million is “high” — water becomes orange or reddish-brown at high concentrations.
On Tuesday, research scientist Rick Bartleson of the Sanibel-Captiva Conservation Foundation counted 15 million Karenia cells per liter in water samples from Sanibel Boat Ramp.
“You could see the bloom,” Bartleson said Thursday. “There were really high concentrations in that area. As I was driving over the causeway today, I could see dead fish floating. They were abundant.”
Concentrations had dropped to 2 million at the boat ramp by Thursday, when Bartleson recorded counts of 4.7 million at Tarpon Bay and low concentrations at the Tarpon Bay Road beach.
Tim said: “It does kind of make you wonder what’s up here. We walked up and saw the fish on the beach and said, ‘What’s up with that?’ because we wondered if it was harmful to humans.”
Earlier this week, Bob Wasno, education and resource coordinator at FGCU’s Vester Marine Field Station, saw evidence of red tide while fishing 13 miles off Big Hickory Pass.
“The water was absolutely orange down to 7 or 8 feet,” he said. “Despite that, we caught some nice snapper, but we didn’t see a single dead fish. We put a couple of snapper in the live well, and they didn’t last but two or three minutes.”
As of Thursday, the fish kill was concentrated in the San Carlos Bay area.
John Jensen, co-owner of Jensen’s Twin Palm Cottages and Marina and Jensen’s on the Gulf on Captiva, said he’s seen no signs of red tide.
“I’ve heard people south of us talking about it, but we’re clean in the Gulf and in the bay,” he said. “A strong cold front is moving in early next week. Maybe that will blow it away. We don’t like that stuff.
Dead fish are floating in Lee County waters and washing up on local shorelines again.
The first dead fish associated with a continuing red tide bloom in Southwest Florida were reported Nov. 25 in Estero Bay. Small numbers of dead fish have washed up sporadically since then, and this week, large numbers of dead fish were reported.
Since the bloom started, red tide has killed seven manatees in Lee County and two in Collier County; eight other manatee carcasses recovered in Lee are listed as suspect red tide victims.
“It must have been one big bloom,” said Tim Karas of South Fort Myers, who was stand-up paddle boarding Thursday near the Sanibel Causeway. “I can’t imagine. Today, I didn’t see any dolphins, sharks or manatees. It definitely had an effect on the rest of the wildlife. They must be smart enough to stay away from it.”
Red tide is a natural phenomenon caused by the single-cell alga Karenia brevis, which produces a powerful neurotoxin.
Under normal concentrations, less than 1,000 cells per liter of water, Karenia is not a problem.
But when Karenia undergoes a population explosion, or bloom, the increased toxin can kill fish and other marine organisms and render filter-feeding mollusks poisonous to humans.
It also can cause respiratory irritation in some humans.
Karenia concentrations of 10,000 to 100,000 are classified as “low” and can kill fish; concentrations of of 100,000 to 1 million are “medium,” and more than 1 million is “high” — water becomes orange or reddish-brown at high concentrations.
On Tuesday, research scientist Rick Bartleson of the Sanibel-Captiva Conservation Foundation counted 15 million Karenia cells per liter in water samples from Sanibel Boat Ramp.
“You could see the bloom,” Bartleson said Thursday. “There were really high concentrations in that area. As I was driving over the causeway today, I could see dead fish floating. They were abundant.”
Concentrations had dropped to 2 million at the boat ramp by Thursday, when Bartleson recorded counts of 4.7 million at Tarpon Bay and low concentrations at the Tarpon Bay Road beach.
Tim said: “It does kind of make you wonder what’s up here. We walked up and saw the fish on the beach and said, ‘What’s up with that?’ because we wondered if it was harmful to humans.”
Earlier this week, Bob Wasno, education and resource coordinator at FGCU’s Vester Marine Field Station, saw evidence of red tide while fishing 13 miles off Big Hickory Pass.
“The water was absolutely orange down to 7 or 8 feet,” he said. “Despite that, we caught some nice snapper, but we didn’t see a single dead fish. We put a couple of snapper in the live well, and they didn’t last but two or three minutes.”
As of Thursday, the fish kill was concentrated in the San Carlos Bay area.
John Jensen, co-owner of Jensen’s Twin Palm Cottages and Marina and Jensen’s on the Gulf on Captiva, said he’s seen no signs of red tide.
“I’ve heard people south of us talking about it, but we’re clean in the Gulf and in the bay,” he said. “A strong cold front is moving in early next week. Maybe that will blow it away. We don’t like that stuff.
Walter Karas