Siskiwit Lake

Siskiwit Lake comes in at a B on the grading rubric — a respectable showing for a Wisconsin lake of its size and depth.

A TSI near 50 places Siskiwit Lake in the mesotrophic band — moderate productivity, with seasonal swings between clearer spring water and richer late-summer conditions. Siskiwit Lake is a shallow lake at 13 ft maximum depth, which means it warms quickly, mixes constantly, and amplifies nutrient inputs. The lake's 285 acres and partial shoreline records put it in the mid-range bucket — large enough for varied use, small enough that watershed inputs reach the whole basin. Within the 52 graded lakes of Bayfield County, Siskiwit Lake sits at rank 40, near the bottom of the county list.

Siskiwit Lake has no invasive species recorded in Wisconsin state databases as of 2023, though prevention practices still apply at all access points. The fishery includes walleye among the lake's 5 documented species — a notable draw for Wisconsin anglers. Monitoring depth is thin here: the LakeGrade rubric is applied to a small number of sample years, and the grade will be revised as more data accumulates.