Sea Lamprey
Invasive SpeciesFound in 1 lakes
Sea Lamprey appears on state infested-waters lists for 1 surface waters. Boaters and anglers moving gear in or out of those lakes carry a clean-drain-dry obligation under state law. 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 Sea Lamprey does not directly change a lake's LakeGrade rubric score — the grade measures the water itself, not the species inhabiting it. But invasive presence is a meaningful adjacent signal worth reading alongside the grade.
Lakes with Sea Lamprey
| Lake | County | State | Grade | Depth |
|---|---|---|---|---|
| Lake Ahmik | Keweenaw | MI | B | - |
Frequently Asked Questions
How many lakes have sea lamprey?
Sea Lamprey has been documented in 1 graded lakes: 1 in Michigan.
Does sea lamprey affect water quality?
Invasive species can significantly affect lake ecosystems. They may alter nutrient cycling, displace native species, and change water clarity. Lakes with sea lamprey should be monitored for changes in water quality over time.
Source: EPA National Aquatic Resource Surveys, 2026.