Spiny Waterflea: 53 Lakes with Records

Spiny waterflea is a small zooplankton invasive that disrupts the food web by competing with native zooplankton — the base of the food chain for many small fish. Documented in 53 lakes. 53 infested lakes is enough to require active prevention work statewide. The species is established in pockets but not ubiquitous.

The presence of Spiny Waterflea 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 records

Minnesota

Wisconsin

Lakes with Spiny Waterflea

Lake	County	State	Depth
Clearwater Lake	Cook	MN	65 ft
Trout Lake	Cook	MN	77 ft
Devil Track Lake	Cook	MN	50 ft
Fall Lake	Lake	MN	32 ft
Burntside Lake	St. Louis	MN	126 ft
Gunflint Lake	Cook	MN	200 ft
Flour Lake	Cook	MN	75 ft
Mcfarland Lake	Cook	MN	8 ft
Greenwood Lake	Cook	MN	112 ft
Teal Lake Deep	Cook	MN	-
Little Lake Deep	Cook	MN	-
Snowbank Lake	Lake	MN	150 ft
Spider Lake	Vilas	WI	43 ft
Plum Lake	Vilas	WI	57 ft
Whitefish Lake	Douglas	WI	102 ft
Butternut Lake	Forest	WI	42 ft
Lake Waubesa	Dane	WI	38 ft
East Twin Lake	St. Louis	MN	22 ft
Big Traverse Bay Lake	Lake of the Woods	MN	-
Lake of the Woods	Lake of the Woods	MN	-
Low Lake	Lake of the Woods	MN	-
Bardon Lake	Douglas	WI	102 ft
Lake Kegonsa	Dane	WI	32 ft
Lake Mendota	Dane	WI	83 ft
Kabetogama Lake	St. Louis	MN	80 ft
Rainy Lake	Koochiching	MN	161 ft
Sand Point Lake	St. Louis	MN	184 ft
Crane Lake	St. Louis	MN	80 ft
East Vermilion Lake	St. Louis	MN	76 ft
West Vermilion Lake	St. Louis	MN	76 ft
Bass Lake	St. Louis	MN	-
Crooked Lake	Lake	MN	165 ft
Mille Lacs Lake	Aitkin	MN	42 ft
Red Rock Lake	Cook	MN	64 ft
Basswood Lake	Lake	MN	111 ft
Sucker Lake	Lake	MN	111 ft
Pine Lake	Cook	MN	113 ft
Vermilion Lake	St. Louis	MN	-
Shagawa Lake	St. Louis	MN	48 ft
Lac la Croix Lake	St. Louis	MN	168 ft
Newton Lake	Lake	MN	47 ft
Little Lake Inlet	Cook	MN	-
Little Gunflint Lake	Cook	MN	200 ft
Little Lake Landing	Cook	MN	-
Superior Lake	Cook	MN	-
Island Lake Reservoir	St. Louis	MN	-
Iron Lake	St. Louis	MN	64 ft
Teal Lake Landing	Cook	MN	-
Little Lake Culvert	Cook	MN	-
Ike Walton Lake Deep	Vilas	WI	61 ft

Showing 50 of 53 lakes with a record.

Frequently Asked Questions

How many lakes have spiny waterflea?

Spiny Waterflea is recorded in 53 measured lakes: 41 in Minnesota, 12 in Wisconsin. 53 of them carry a state infested-waters listing or an established population.

Does spiny waterflea 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 spiny waterflea is worth reading alongside its clarity number rather than through it.

Invasives Found With Spiny Waterflea

Zebra Mussel

Co-occurs in 14 lakes · 609 total

Chinese Mystery Snail

Co-occurs in 10 lakes · 469 total

Eurasian Watermilfoil

Co-occurs in 8 lakes · 792 total

New Zealand Mud Snail

Co-occurs in 7 lakes · 7 total

Faucet Snail

Co-occurs in 7 lakes · 39 total

Round Goby

Co-occurs in 7 lakes · 9 total

More on invasive species and lake health

Zebra Mussel Spread: How Many Lakes Are Affected?

Zebra mussel counts from the lakes LakeQuality tracks, the counties that show up most often, and the Clean, Drain, Dry rules that still matter.

Lake Water Quality Explained: What the Readings Mean

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.

What to Check Before Buying Lakefront Property

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.