fish kill – Aquarius-Systems

Chemical Spraying Causes Major Fish Kill in Florida Canal

Tue, 15 Jul 2025 18:18:06 +0000

Following a chemical treatment aimed at controlling aquatic vegetation in Port St. Lucie’s Elkhorn Canal, residents reported what they called the “worst smell in the entire world” as countless fish perished on the canal’s surface. Water tests revealed that dissolved oxygen levels plunged to levels unsustainable for aquatic life—an unintended but severe consequence of the applied chemicals.

Critics argue that proper dissolved-oxygen testing should have been completed before treatment—something the contractor failed to do. Environmental advocates now recommend exploring safer alternatives, such as mechanical harvesting or biological controls, to manage vegetation without triggering oxygen depletion or fish kills.

Lake Hopatcong Harvesting Removes 800 Tons of Weeds

Mon, 04 Dec 2023 21:35:32 +0000

Dan Bello, who is supervising the weed control program for the state park, told the Lake Hopatcong Commission on July 21 that the weed harvesters on Lake Hopatcong in New Jersey brought in 800 tons of weeds between June 6 and July 18. According to Bello, that averages about 27 cubic yards a day. In comparison, last year only about 270 tons of weeds were harvested by July 18.

One of the harvesters was also dispatched to assist with a major fish kill. According to Park Superintendent Steve Ellis, the lack of oxygen in places where herbicides were applied can kill fish.

Are Fish Populations affected by Chemical Treatments?

Fri, 01 Dec 2023 19:05:17 +0000

David Tyler, publisher of the Cazenovia Republican in Cazenovia New York appreciates and applauds the efforts of the Cazenovia Lake Association and the Lake Watershed Council in their efforts to maintain the health of the lake. With that said, he questions the effect of herbicide treatments on the size and number of fishing being caught.

A two-year program to treat Eurasian milfoil with herbicide has seemed to reduce and eliminate the aquatic invasive species in part of the lake, but the downturn in fishing and a fishkill event last summer has cause for concern. He questions the timing of the events and speculates that perhaps the herbicides have caused the latest issues.

Algae Treatment Leads to Massive Fish Kill in Lake Isabella

Fri, 01 Dec 2023 18:16:49 +0000

Lake Isabella has experienced a significant “fish kill” due to low oxygen levels following treatment of an extremely high blue-green algae presence.

When the heavy bloom was noted a recommendation was made to close the lake to swimming and boaters and a company was hired to treat the lake with a chemical called SeClear. The following day, hundreds of dead fish were observed lying dead on the bottom and floating on the surface.

Workers went around netting the dead fish. The numbers showed 1,105 small largemouth bass killed, 181,888 bluegill fingerlings, 7,635 larger bluegill, 26 white crappie, 3 grass carp and 10 channel catfish killed. All of the fish were buried in the Village gravel pit.

Fish Kill In Bayou Rouge Due in Part to Herbicide Treatment

Tue, 21 Jun 2022 15:19:30 +0000

Following reports of hundreds of dead fish floating in Bayou Rouge in Cottonport, Louisiana, the Louisiana Department of Wildlife and Fisheries (LDWF) conducted an investigation to find out what caused the fish kill.

Officials determined that that fish died from a low dissolved oxygen level in the water, basically suffocating the fish.

The low dissolved oxygen level was a result of multiple factors. Days before the fish kill, LDWF treated Bayou Rouge with a herbicide that targets specific plant life in the bayou and is deemed safe for aquatic animals. The decaying plant life at the bottom of the bayou from the herbicide, combined with the hot water temperatures, was stirred by the heavy rainfall. Those factors severely reduced the dissolved oxygen in the water, killing the fish.

“I do not know if there would have been a fish kill if we had not done the herbicide treatment,” said Daniel Hill, LDWF Biologist Manager Inland for Region Six. “It was very unfortunate timing.”

Winterkill Can Have Devastating Effects on Fish Populations

Tue, 18 Jan 2022 16:01:17 +0000

Winterkill occurs when fish suffocate due to a lack of dissolved oxygen in the water and is the most common type of fish kill. Dissolved oxygen is required by fish and almost all other forms of life living in water bodies. Even bacteria living on lake bottoms require dissolved oxygen to survive.

Low oxygen levels are the result of various factors. When ice and snow begin to cover water bodies, the amount of sunlight penetrating into the water becomes limited. Aquatic vegetation is then unable to produce an abundant amount of oxygen. Like in terrestrial habitats, a large proportion of oxygen in the water is produced by plants. If plants do not have sunlight to allow for natural processes, the oxygen byproduct is not produced.

Learn More https://www.sooeveningnews.com/story/opinion/2021/12/14/winterkill-do-fish-need-oxygen-too/6491918001/

Fish Found Dead after Chemical Treatment

Wed, 05 Jan 2022 22:15:31 +0000

A heat wave combined with a chemical treatment for weeds proved to be deadly to some fish in Bon Aire Lake, according to the executive director of Merrillville Stormwater Utility.

Matt Lake said about 100 fish died recently in an isolated incident in the 21-acre lake when the heat index rose to 110 degrees the day after the lake was treated for algae, duckweed and other noxious weeds.

“Some fish suffocated. It happens, primarily at the outlets of the lake,” Lake said.

Chemical Treatment Kills Thousands of Fish in Hartwell Lake

Wed, 05 Jan 2022 22:03:41 +0000

About 5,000 fish have died because of algaecides applied to Hartwell Lake in an effort to improve the region’s drinking water. The South Carolina Department of Natural Resources and the state’s public-health agency are investigating the fish kill, which affects the area around the Anderson Joint Regional Water System’s intake on the lake.

160 acres of the lake was treated with algaecides to try to improve the taste and smell of customers’ drinking water. The Copper and hydrogen peroxide based algaecide was applied in granular form and in concentrations low enough not to harm fish or people.

The algaecide was applied in accordance with regulations approved by the U.S. Environmental Protection Agency. Officials believe it “is likely a one-time event” and that the water is “safe for human and wildlife exposure.” Although, a spokesman for the Army Corps of Engineers were not surprised by the fish kill. “Small Fish are susceptible to dying when they come in contact with algaecides.”

10,000 Dead Fish at Lake Mission Viejo after Toxic Algae Outbreak

Wed, 05 Jan 2022 21:34:54 +0000

An outbreak of toxic algae has killed almost all fish at Lake Mission Viejo, a world-class bass fishery in California.

An estimated 10,000-plus bass, catfish, sunfish and blue gill have died in the past few months at the man-made recreational lake, said Kevin Frabotta, general manager of the Lake Mission Viejo Association, the homeowners association that owns the lake.

Lake staff discovered dead fish in early November and lab tests showed they were dying as a result of a toxin produced by prymnesium parvum, also known as the golden algae, the HOA website stated. HOA employees have been treating the lake with algae suppressor and testing water samples twice a week since then, Frabotta said.

Staff stock Lake Mission Viejo with trout every winter, but the association has been delaying restocking until the lake condition recovers. They’ve released about 15 sample trout to test the water, but all died within two hours, Frabotta said.

Suburban Chicago Lake’s Fish Kill Sparked by Herbicide Treatment

Wed, 29 Dec 2021 22:28:57 +0000

Suburban Chicago official says hundreds of fish died in the community’s lake when oxygen levels plummeted after an herbicide was applied to combat aquatic plants.

About 400 fish, including largemouth bass, died last week in Libertyville Illinois’s Butler Lake soon after a company applied a chemical that’s designed to control invasive weeds, including the lake’s excessive growth of water lilies.

Libertyville public works director Paul Kendzior tells The Daily Herald that the vegetation die-off caused dissolved oxygen levels to fall, depriving fish of oxygen and killing them. He says the herbicide application itself didn’t directly harm the fish.