AUSTIN (KXAN) — Lake Waco, a favorite spot for boaters and fishermen, recently received a unique distinction – it is the only reservoir in Texas to have eradicated its zebra mussel population.
The lake earned the title back in 2021 after a five-year survey of the waters following an infestation that began the same year.
As part of Earth Week, we’re taking a closer look at this project and what we can learn from it.
Why zebra mussels are bad for the environment
“We really have the perfect habitat for them to exploit and spread out of control,” said Chase Smith Ph.D., a freshwater mussel researcher at the University of Texas. Smith says zebra mussels were first introduced to North America in the 1980s, likely by a boat traveling from Russia.
In the last 20 years, the clams have made their way to Texas and greatly impacted our waterways.
“They will actually take all of the nutrients from the habitats that they are in,” Smith said. This can be bad for wildlife in these waterways, especially other freshwater mussels.
“They’re actually going to latch on to the freshwater clams and choke and kill them,” Smith said. In a healthy environment, Smith said, freshwater mussels filter every drop of water that flows down a river.
Zebra mussels can attach themselves to some difficult surfaces, including pipes and boats. They can damage water pipes and other utility equipment.
However, zebra mussels also filter water.
“If you consider that a zebra mussel can filter a gallon of water or more every day, and you have a population of hundreds of thousands, maybe millions of mussels that are doing this every day, day in and day out. Over time, these reservoirs tend to clear up,” said Michael Baird of Texas Parks and Wildlife.
The Lake Waco Zebra Mussel Project
Baird was part of the team that eradicated the clams in Lake Waco. In 2014, Texas Parks and Wildlife trained employees in Waco to identify zebra mussels. In September of that year, the training paid off. Around 80 seashells were found at a dock on Lake Waco. They were launched into the water from a boat that recently visited Lake Belton, which is infested with the creatures.
Just before the clams spread to the rest of the lake, Tom Connery, a city employee, had a plan.
“Smother any remaining zebra mussels in the area by laying out large sheets of plastic and weighing them down with sandbags,” Baird said.
Then they waited. When they searched the water for young juvenile zebra mussels, they could not find any. “Nothing in the next five years, we didn’t find anything. By 2021 the lake is said to have been free of zebra mussels.”
Smith said the plastic method likely did one of two things — suffocate them and deprive them of oxygen, or overheat them. Zebra mussels only thrive in certain water temperatures and can survive extreme heat.
Zebra mussels all over Texas
Baird said 30-40 Texas reservoirs are currently infested with zebra mussels. Lake Waco is the only one that has eradicated them. He said it was possible because the clams were caught so early.
“If you find out five or six months later, it’s probably too late by that point,” Baird said.
“I don’t think it’s possible in the United States to turn them off at this point, but I think, you know, over time there’s certainly a way we can control them,” Smith said.
As an example, he cited the Asian clam, an invasive species that is now found in many lakes and has become part of the ecosystem.
Smith said using chemicals or introducing a predator to eliminate the zebra mussel could be hazardous to the entire ecosystem. Baird agrees, saying the only way to protect native wildlife is to prevent them from spreading.
So how do we prevent its spread?
- Boaters must clean, drain, and dry their boats after leaving the lake and before entering a lake. Zebra mussels spread by attaching themselves to boats.
- Learn to identify zebra mussels so authorities can take action before they get out of hand.
- If zebra mussels are found, and in low enough numbers, getting creative, like Lake Waco’s plastic wrap method, might work.
https://www.kxan.com/weather-traffic-qas/texas-lake-eradicates-zebra-mussels-heres-how-they-did-it/ Texas Lake wipes out zebra mussels – this is how it happened