MINNEAPOLIS (WCCO) — Two weeks ago, Trevor Clayton and his girlfriend were walking near Lake Hiawatha. They sat down on a log nearby the shore and saw what looked like a “shiny alien” sitting in shallow water. It wasn’t moving at all.
“If you’ve ever seen one before, it’s kind of unnerving, they don’t look like they’re of this Earth,” Clayton said. “We were both like WTF, what is this thing?”
According to Gary Montz, an aquatic invertebrate biologist with the Minnesota Department of Natural Resources, this “thing” is a colony of bryozoans.
“It’s this big gel blob,” said Montz. “What it’s composed off is tiny little bryozoan animals that have made their little homes and glued them together into this enormous apartment complex of bryozoans.”
Montz wrote about what he calls “moss animals” for the Minnesota Conservation Volunteer.
Last week, City Pages wrote an article about the sea creatures when people were posting on the Nextdoor app asking what they were.
Montz said the bryozoan colonies are totally normal in creeks, lakes and wetlands. He’s not sure why they’re getting more attention this summer but speculates it could be because of the weather, water currents or more people being outside due to the pandemic.
The colonies generally attach to objects in the water like docks, rocks or sticks. They don’t move unless the water carries them. By fall, they die off, but not before leaving behind discs that will grow into more bryozoans the following spring.
“It’s not going to hurt you, it’s not toxic, it doesn’t sting because they’re microscopic,” Montz said. “It’s just out there.”
Some fish or snails might nibble on them and bryozoans do filter the water when they eat, but Montz said there aren’t enough of the creatures in the waterways to make a difference in the lake’s ecosystem.
“They’re just one of those odd animals out there out there in our ecosystem just living in our lakes and rivers,” he said. “It’s pretty amazing that in this brownish, green looking thing are actually thousands of tiny, living animals living their lives.”