Iowa River Mussel Population Falling

Sep 24, 2018

Photo courtesy of Aaron McFarlane with the Corps of Engineers

The number of mussels in the Iowa River is falling, but scientists don't really know why. That's one of the results of this year's Iowa Mussel Blitz. 

Fisheries biologist Scott Gritters from the Iowa DNR says there are about 42 species of native mussels in Iowa and despite the population decrease, there's still scattered locations where they are healthy and thriving.

"It's been a typical pattern of our interior rivers in Iowa. You know, we go miles sometimes without finding hardly any mussels and then there is some sort of pocket of really quality habitat, and that's where we find them."

The 13th Annual Iowa Mussel Blitz was held in August. Scientists, students, and volunteers worked together to collect and record data along the Iowa River, from the Coralville Dam to Hills.

"The public definitely has affinity to recreating on clean water. Mussels do the best when we have the best water quality, the best habitat, and the best places to fish. So  if we can just try to use them as an indicator  to try to improve our water quality in our rivers, I think the public will be benefitted."

Gritters says the Iowa River probably has a healthy population of mussels, but during the week long blitz, they were only able to survey about 3 percent of the population. 

The Iowa DNR is also trying to boost mussels count in the Cedar and Wapsipinicon rivers.