Red Swamp Crayfish
Invasive speciesRecorded in 1 lake
Red Swamp Crayfish is documented in 1 lakes across our dataset — 1 in Wisconsin. Each state's natural-resources agency maintains an official "infested waters" roster that triggers boat-launch decontamination protocols. 1 lakes — narrow enough that aggressive containment is still on the table. Most upper-Midwest invasives that established here did so quietly over a decade before anyone noticed, so a low number today is not a guarantee for tomorrow.
The presence of Red Swamp Crayfish does not change a lake's clarity, phosphorus or algae readings, which measure the water itself, not the species living in it. Invasive presence is still worth reading alongside those numbers.
Lakes with Red Swamp Crayfish
| Lake | County | State | Depth |
|---|---|---|---|
| Altoona Lake | Eau Claire | WI | 25 ft |
Frequently Asked Questions
How many lakes have red swamp crayfish?
Red Swamp Crayfish is recorded in 1 measured lakes: 1 in Wisconsin. 1 of them carry a state infested-waters listing or an established population.
Does red swamp crayfish affect water quality?
An established invasive population can change how a lake works — altering nutrient cycling, displacing native species, and shifting water clarity. Clarity is the one to watch: filter-feeders can make water read clearer on a Secchi disk without any drop in nutrient loading, so a lake with red swamp crayfish is worth reading alongside its clarity number rather than through it.
Invasives Found With Red Swamp Crayfish
More on invasive species and lake health
Zebra mussel counts from the lakes LakeQuality tracks, the counties that show up most often, and the Clean, Drain, Dry rules that still matter.
How nutrient and algae readings are read against EPA ecoregion condition classes, what each class means in the water, and why a clean reading is not a clearance.
Before you buy lakefront, check the water: clarity trend, nutrient impairment, algae advisories, invasive species, and depth — a data-backed checklist.
Source: EPA National Aquatic Resource Surveys, 2026.