Mussel 'spits out' toxic microcystin, plays part in Erie algae

Non-toxic algae is already forming on Lake Erie: you can already see it showing up from space, on some NASA satellite images.

By now we know the causes of our late summer algae blooms, just like the bloom that caused Toledo's 2014 water crisis. But one animal hides at the bottom of the lake, and gets virtually no attention - until now.

We're talking about the Quagga Mussel. It's about the size of your thumb nail. Even though it's tiny, it plays a big role in our algae blooms. And it has a special ability.

"Spit out stuff they don't like. And microcystis is something they don't like," Dr. Hank Vanderploeg said. He is Branch Chief at NOAA's Great Lake Environmental Research Laboratory in Ann Arbor.

That's right: the mussels spit out the bad and keep the good, like nutrients. That makes for clearer water, which the microcystis needs to grow, as a form of blue-green algae.

"They'll also excrete nutrients from their feeding process," Dr. Tom Johengen said. "So that's going to promote the growth of the microcystis, which they've rejected."

Dr. Hank Vanderploeg has researched these mussels for decades, alongside Dr. Johengen. Vanderploeg says they can live places the infamous zebra mussels simply can't.

"In many areas they've actually replaced the zebra mussels," Dr. Vanderploeg said.

"Even if you tried to treat an area where they exist, the next generation would just come and settle right in the area that you just cleaned them from," Dr. Johengen said.

Johengen works for the Cooperative Institute For Great Lakes Research. Both scientists work in the lab and on the boat.

And both have concern about might happen if we somehow clean up what's going into Lake Erie.

"As the nutrients become lower and lower, that may provide an opening for the Quagga mussels to exert a stronger influence."

For now, researchers say phosphorous and sewage are the worst players in algae growth and fuel. But these mussels hold their own as a factor in algae growth, too.

"The mussels grow so thick," Dr. Vanderploeg said.

The Quagga mussels grow so fast they have to be hand scraped-off of buoys every month during the summer.