Sucker Monitoring

Milwaukee Riverkeeper participates in ongoing research with the Shedd Aquarium’s Migratory Fish Monitoring Program. Our team helps track the spring migration of sucker fish. Each spring, suckers (both white and longnose) migrate from the open waters of Lake Michigan to their spawning habitats in local rivers and streams. These fish are common, widespread, and easy to identify, as well as ecologically important to our streams.

The Migratory Fish Monitoring Program uses community science to understand the timing of sucker migrations as well as the role of environmental cues, such as water temperature and flow, in triggering sucker spawning. By comparing migration data from year to year, we can better understand the sucker’s role in our stream ecosystems, as well as the local impacts of climate change in the Great Lakes and our own backyards

Why Do We Monitor Suckers?

Suckers migrate early in the year in many Great Lakes tributaries, bringing needed food and nutrients to many other animals and organisms in the watershed. The timing of this cycle has begun to change, which could have an effect on many other parts of the aquatic ecosystem. Dams and other obstructions can also stop this migration, and impair natural ecological cycles.

Why Should We Protect Suckers?

Many see sucker fish as undesirable, but these bottom feeders are ecologically important to our streams. They are a food source for people, fish, mammals and birds. While the fishes are in their spawning streams, their eggs and waste products enrich the entire food web by adding essential nutrients to the streams during early spring when there are not that many other food sources. Many people think that suckers die after they spawn, and even kill them, but this is not true. Suckers can return to the same streams for a long time. They run at the same time as sturgeon and are important to Native peoples.