Birders, environmental groups alarmed by proposed Lake Mattamuskeet algae treatment

Environmentalists and bird watchers are worried about a state-funded proposal to use an algae-killing chemical to try to remove toxins from an environmentally challenged Eastern North Carolina bird refuge despite warnings that the chemical is toxic to birds.

North Carolina’s 2021 state budget allocated $5 million to the N.C. Policy Collaboratory to study how a chemical would treat harmful algae blooms on large water bodies throughout the state. Language in the carefully written budget provision gives “a preference” to products that float on the surface and that time release their chemicals.

Floating and being time released are the two traits that set apart Lake Guard Oxy, a product created by Israeli company BlueGreen Water Technologies that the Collaboratory ultimately chose for the pilot program. BlueGreen has hired lobbyists in North Carolina since 2021, according to records from the N.C. Secretary of State’s office.

“They’re the only ones that met the requirements of the legislation,” Jeff Warren, the executive director of the Collaboratory, told The News & Observer. Warren said the Collaboratory was not involved in crafting the provision.

Working with the Collaboratory, BlueGreen considered five different bodies of water in the state and ultimately landed on Lake Mattamuskeet, a U.S. National Wildlife Refuge beloved by birdwatchers who travel there every winter to watch migrating ducks and tundra swans that visit the key stop on the Atlantic Flyway.

Those birdwatchers and environmental groups are specifically concerned about a warning on Lake Guard Oxy’s label that says it is toxic to birds.

“To us, that should be a red light to use on a National Wildlife Refuge that is established by Congress as an inviolate sanctuary for migratory birds and is extremely important for water fowl and other migratory birds,” Derb Carter, a Southern Environmental Law Center senior attorney, told The News & Observer.

BlueGreen does not believe Lake Guard Oxy would harm any wildlife, Jessica Frost, the company’s science director, told The N&O.

“There have been numerous applications of Lake Guard Oxy in aquatic environments with existing birds and there has never been an adverse impact,” Frost wrote in an email. She said migratory bird activity actually increased at one reservoir after the chemical’s use, presumably because it made the water there clearer.

Frost added that third-party labs have looked at whether Lake Guard Oxy has detrimental impacts on water fleas, honeybees and mallards. When the chemical is applied at levels and according to protocols recommended on the labels, Frost said, it has been shown to be safe to wildlife.

Algae on Lake Mattamuskeet

Records obtained by the Southern Environmental Law Center and shared with The N&O indicate it was professors from UNC’s Institute of Marine Sciences who first suggested Lake Mattamuskeet as a potential site for the pilot program.

Nathan Hall, an assistant professor who has extensively studied algae, wrote an email to a U.S. Fish and Wildlife Service official on Aug. 3, 2022, suggesting the lake as a potential site for the project.

“I usually don’t like these types of techno fixes but in this case I feel like it wouldn’t hurt to try, and it might actually help,” Hall wrote, later asking, “Do you think there’s a snowball chance in hell that the USFWS would go for this?”

The U.S. Fish and Wildlife Service did go for it.

For the chemical to be used on the lake, the Fish and Wildlife Service must deem it compatible with the purposes of the refuge. In a draft environmental assessment recommending moving forward with the proposal, Mattamuskeet National Wildlife Refuge officials said reducing the amount of cyanobacteria in the lake would help clean the lake’s water, boosting the ecosystem and helping native birds and fish that depend on it.

According to the assessment, the pilot would take place in four coves covering about 600 acres of the 40,276-acre lake. Turbidity curtains would be used to keep the chemicals in place.

Lake Mattamuskeet was once dominated by submerged aquatic vegetation that helped feed more than 250,000 migrating birds like ducks, geese and swans. By the early 1990s, the lake had started to lose that vegetation, something the Fish and Wildlife Service attributes to invasive carp, increased nitrogen and phosphorous, and the harmful algae blooms that result from those nutrients.

Algae blooms affect submerged aquatic vegetation by making it difficult for sunlight to penetrate the water.

Those changes ultimately resulted in the N.C. Department of Environmental Quality placing Lake Mattamuskeet on its list of impaired waters.

“Cyanobacteria treatments may be a valuable component of a larger effort to improve the lake’s biological integrity, diversity, and environmental health. Treating these algal blooms may be an important step in (submerged aquatic vegetation) restoration, which is imperative for the refuge to meet its goals and objectives,” the environmental assessment says.

Phillip Doerr, a retired N.C. State University wildlife ecologist, has been visiting Mattamuskeet for 50 years. As a professor, he would frequently take classes there.

Doerr is particularly concerned about the details of how and when Lake Guard Oxy would be applied. The environmental assessment says it could be put on the water in winter or spring and either applied aerially or via a boat.

Having the specific details about that application matters, said Doerr, who recalls seeing dead and dying swans when decades ago when Mattamuskeet enountered another crisis, that one inflicted by lead shot that built up around duck blinds.

“We’re concerned about it and we want to treat it right, we want to conserve and we don’t want to mistreat it. If something like this is going to happen, it certainly needs to be done on a slow track,” Doerr said.

Other ways of limiting nutrients?

Carter and other advocates argue that without finding ways to keep nitrogen and phosphorous from reaching Mattamuskeet, the lake would just need to be treated over and over with Lake Guard Oxy or a similar chemical.

“The underlying problem is excessive nutrient input into the lake and this will do nothing — nothing — to address that,” Carter said.

In 2019, the N.C. Coastal Federation completed the Lake Mattamuskeet Watershed Restoration Plan for the U.S. Fish and Wildlife Service and Hyde County. That plan called for a reduction in carp, but also called for a reduction in nutrients from runoff. The $5 million going to the Lake Guard Oxy project would be better spent, Carter said, implementing strategies that reduce that runoff.

Alyson Flynn, a Coastal Federation environmental economist and coastal advocate, argued in a comment to the Fish and Wildlife Service that the pilot project is incompatible with the watershed restoration plan because it doesn’t address that root problem of too many nutrients.

“To combat nutrient runoff into the lake, key interagency and community stakeholders have been working with engineering consultants since 2020 to develop a hydrological model of the lake and prioritize alternatives for active water management within the watershed,” Flynn wrote.

Those efforts are moving forward, Flynn wrote, adding that Hyde County recently approved funding for surveying and wetland restoration design that would help with projects meant to redirect nutrient-laden runoff into restored wetlands before it could reach the lake.

Frost, the BlueGreen science director, said Lake Minneola in Florida has stayed free of algae blooms after being treated with Lake Guard Oxy in 2020 and 2021 even as lakes upstream have continued to struggle.

“A core component of study in Lake Mattamuskeet pertains to how competing, beneficial organisms can regain a competitive balance against cyanobacteria blooms. BlueGreen advocates for preventive or proactive management of natural resources, such as Lake Mattamuskeet, rather than the typical reactive responses by local government,” Frost wrote.

For that reason, Frost wrote, BlueGreen encourages the managers of the water bodies it treats to develop plans specifically designed to reduce harmful algae blooms, especially if they’re key recreational areas or important to wildlife.

“Developing a HAB Management Plan will undoubtedly support conservation efforts and the safety of wildlife and humans,” Frost wrote.

Using Lake Guard in less than 3 feet of water?

Advocates believe that another geographic feature of the lake should make officials wary of treating it with Lake Guard Oxy.

Until early 2023, Lake Guard Oxy’s label also said it should not be used in water less than three feet deep. That would rule out use across virtually all of Mattamuskeet, which averages a foot-and-a-half in depth.

When asked why the three-foot requirement had been stricken from the label, an EPA spokesman told The N&O, “The registrant notified EPA that it was removing the following statement from the Lake Guard Oxy label: ‘Do not apply to shallow water bodies less than three feet deep, or to areas where surface water is stagnant.’ EPA found that the action requested fell within the scope of PRN 98-10 and, as a result, acknowledged the label notification in a letter dated March 6, 2023.”

BlueGreen officials told The N&O they originally put the depth limitation on the label voluntarily as part of an effort to deter people from using the chemical to treat manmade or at-home water features that don’t have a natural current or dilution that results from mixing.

“Through ongoing BlueGreen treatments and collection of data ... BlueGreen determined that the floating characteristics of the product enables a dependable upper-layer activation without substantial oxidation below the surface of the water,” Frost wrote.

Carter and other environmental advocates are skeptical about whether the label change does fall within the scope of Pesticide Registration Notice 98-10. That regulation typically allows changes to labels for things like changes in brand names, adding claims that the chemical can be used to treat for certain pests, or changes in how the chemical is packaged.

“We read that thing front to end and see no basis for this type of a change,” said Carter, who added that the request seemingly came after SELC requested records on Lake Guard Oxy from the Collaboratory and noted that the label perhaps made Lake Mattamuskeet an inappropriate place for its use.

Flynn, of the Coastal Federation, also called for more transparency around that change to the label. The EPA approved the change, Flynn noted, about a month after a group of Lake Mattamuskeet Watershed Restoration Plan stakeholders raised concerns about the label.

“In order to fully address stakeholder concerns, formal details should be provided in this assessment as to what process and scientific rigor occurred in order for this label amendment to safely occur,” Flynn wrote.

Outside of the environmental impact, the change is important for another reason. The Collaboratory’s invitation for bids stated that the chemical ultimately chosen must be able to be used without consideration for the size or shape of the water body where it would be applied.

“Lake Guard Oxy’s label, at the time it was selected, prohibited use on the shallow waters of Lake Mattamuskeet and it was not ready to use without limitation as required by the Collaboratory solicitation. This is further evidence the decision to purchase and use the product was predetermined by the legislature,” SELC Senior Attorney Ramona McGee told The News & Observer.

The Collaboratory’s review of two bids noted that both Lake Guard Oxy and another company’s proposal scored low for use on water bodies of any size.

“The devil in the details there is part of the regulatory process,” Warren told the N&O. “It’s going to be up to the feds because it’s their water body and the state to determine if they’re comfortable with putting this in whatever water body.”

BlueGreen would likely need to obtain an additional permit from DEQ before applying Lake Guard Oxy. That permit may be a pesticide application permit, a DEQ spokesman told The N&O.

This story was produced with financial support from the Hartfield Foundation and 1Earth Fund, in partnership with Journalism Funding Partners, as part of an independent journalism fellowship program. The N&O maintains full editorial control of the work.