Inside a St. Paul lab’s battle against aquatic invaders
Published 1:10 pm Saturday, September 23, 2017
By Kirsti Marohn
In a lab on the University of Minnesota’s St. Paul campus, bright green plants float in water-filled washtubs beneath glowing fluorescent lights.
Here, researchers are actually trying to grow one of the state’s most dreaded aquatic invaders.
“Right here in the middle, we have starry stonewort, which is Minnesota’s newest invasive species on the scene,” program coordinator Pat Mulcahy said.
Mulcahy and other researchers are cultivating the pesky algae to figure out what conditions it grows best in, which could help identify the Minnesota lakes most at risk of becoming infested.
At the Minnesota Aquatic Invasive Species Research Center, scientists are working to help policymakers figure out how to battle these invaders. Last week, the center opened its lab doors to the public to highlight a few of its projects during its annual AIS Showcase.
“It’s hitting people closer and closer to home,” said Nick Phelps, the center’s director. “Their favorite lakes are becoming invaded and probably the most likely way toward a solution is through research. So, they come here, learn what they can and then bring that back home so they can use it.”
Invasives hit home for Cheri Fink. In fact, they hit right on her feet. She lives on Clearwater Lake in Annandale, which has Eurasian water milfoil. Zebra mussels were discovered two years ago, too.
Now, Fink has to wear shoes in the water so they don’t cut her feet. She attended the AIS Showcase recently to see how Minnesota is trying to fight aquatic invaders like zebra mussels or the invasive milfoil.
“Our waters are so important to us and to the economy of the state and to our health,” Fink said. “So I’m here to see what we’re doing in Minnesota.”
The Minnesota Aquatic Invasive Species Research Center was created in 2012 with funding from the Environment and Natural Resources Trust Fund and the state’s Clean Water Fund. The center got a big boost this year when the Legislature included $410,000 a year in the state budget.
Its goal is to use science to help inform policy decisions about aquatic invasive species, Phelps said. The center has about 30 projects underway studying 10 different invasive species.
Many Minnesotans are familiar with the mantra that they should clean, drain and dry their boats to avoid transporting invasive plants and animals. Phelps said that advice is still important.
But he said there are many other ways to tackle the problem that focus on prevention, early detection and trying to manage an invasive species when it does show up in a lake or river.
Some of those efforts are aimed at determining which lakes and rivers are most at risk of infestation, Phelps said, so inspection and decontamination efforts can be targeted.
“Unfortunately, some lakes, if zebra mussels were to show up, would be perfect homes for them. Other lakes won’t be,” he said. “So trying to figure out which lakes those are is very, very important.”
Researchers at the center are also trying to determine exactly how these invaders are hitching a ride from one lake to another.
Valerie Brady studies spiny waterfleas, tiny creatures that have infested about 40 Minnesota lakes.
“What we’re trying to figure out is which types of things that people have on a fishing boat are most entangling spiny waterflea, and thus are most risky in terms of transporting them to uninfected lakes,” she said.
Brady’s team sends out a test boat rigged with different types of fishing gear. Then they see how many spiny waterfleas attach themselves.
“Our hope is that with this research we can nuance the clean, drain, dry message,” Brady said. “Like, did you forget to spray off your anchor rope? Or maybe don’t use braided line on this lake.”
Spiny waterfleas are voracious eaters, Brady said. In some lakes, they’ve reduced the amount of tiny zooplankton by as much as 50 percent.
Then, “the baby fish suddenly have only half the food to eat that they had before,” she said. “That’s why we care about these things — other than they’re a pain in the butt and they don’t belong here.”