Bone Lake

Bone Lake comes in at a B on the grading rubric — a respectable showing for a Wisconsin lake of its size and depth. Sub-grades cluster within a single letter of each other, which usually means the lake is in stable trophic balance rather than fighting one specific stressor.

Mesotrophic conditions dominate at Bone Lake: enough nutrients for a healthy fishery, not so much that algal blooms become a chronic problem. The lake bottoms out at 43 ft — a moderate depth that supports a warm-water fishery without the year-round cold refuge a deeper basin provides. With 1,667 acres of surface and partial shoreline records, Bone Lake is a large water by Wisconsin standards — recreational pressure is spread across a long shoreline. Bone Lake ranks 27 of 74 in Polk County — solidly in the upper half of the local distribution.

Zebra mussels have been documented at Bone Lake, which alters the filter-feeding balance and can paradoxically increase water clarity while disrupting the food web. Bass fishing is part of the appeal: the species list runs to 4, anchored by largemouth and/or smallmouth bass. Public access is available — the lake is on the Wisconsin DNR public-access list. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.