Birch Lake is a 76 acre lake located in north central Wright County with a maximum depth of 52 feet. Dissolved oxygen was present to 17 feet in mid-July. The secchi depth was 11.0 feet. The aquatic plant community was diverse with 17 submersed species, some of which grew to a depth of 18 feet. Northern milfoil, flatstem pondweed, Elodea and coontail were common or abundant. The lake is managed for naturally occurring species.
This was the first survey since 1989.
Eighty largemouth bass were taken in slightly less than one hour of electrofishing during the evening of 5/4/09. The catch rate of 82.4 fish per hour was greater than average for Wright County lakes. Anglers can expect good fishing for smaller sized largemouth. Largemouth bass grew slowly so it is important to release a portion of the catch.
Northern pike were abundant and the catch was above the normal range for lakes like Birch Lake. Birch Lake fits a recognizable pattern, i.e. a clear-water lake with abundant vegetation where small northern pike, largemouth bass and sunfish are abundant and perch and crappies are not. Anglers can expect good fishing for small northern pike which will average 18 inches and about one and a half pounds. Northern pike growth was similar to statewide averages. Female northern pike reached 23 inches in four years, whereas males reached 21.5 inches in the same length of time. Two percent of northern pike were longer than 24 inches.
The trap net catch of bluegill was similar to 1989 and within the range of expected values. Bluegill ranged from 4 to 7 inches and averaged 0.12 pounds. Growth was slower than statewide averages. Bluegill grew to length of six inches in seven years.
No black crappies were taken in trap nets. Gill net catches were low continuing a pattern since 1983. Black crappie grew at a rate close to the statewide average and grew to a length of eight inches in four years.
No yellow perch were collected by any gear. Blacknose shiners and banded killifish, sensitive species, were sampled by shoreline seining. Other fish collected in 2009 were black, brown and yellow bullheads, common carp, and pumpkinseed sunfish.