BirdAnalyst
Species · Wisconsin · BBS 2025 Release · 1966–2024

Brown Thrasher Population Trend in Wisconsin

All statesGeneralists

Brown Thrasher in Wisconsin has fallen sharply: down 54% on the route-weighted index since 1968.

-54%Since 1968
98Routes In State
58Years

Notable Brown Thrasher Trends in Wisconsin

long arc declinecomputed index

Brown Thrasher has fallen sharply in Wisconsin: down 54% on the route-weighted index since 1968.

Brown Thrasher Population Forecast in Wisconsin

If the recent trend holds, Brown Thrasher in Wisconsin is projected to fall about 29% by 2029 — from 1.8 in 2024 to a central estimate of 1.3 (95% range 0.24–2.3). A 5-year backtest shows a typical error of ±32.8%, with 80% of held-out values landing inside the 95% band.

-29%Change by 2029
1.3Projected 2029 index
0.24–2.395% range
±32.8%Backtest error
19662029
Projection of the recent trend (dashed) with 80/95% bands — a projection, not a prediction. Habitat, climate, and land use are not modeled.
YearProjected index95% low95% high
20251.50.472.5
20261.50.412.5
20271.40.352.4
20281.30.292.4
20291.30.242.3

Brown Thrasher Survey Routes in Wisconsin

Routes recording Brown Thrasher in Wisconsin.
Buena Vista1420241998
Briggsville1020241999
N Andover820241967
Wiota820241966
Minong620241967
Cumberland620231966
Highland620241998
Beloit620231998
Hatfield519981970
N Freedom520241966
Meridean520231998
Gresham520241998
Weyerhauser420231966
Omro420011966
Casco420241970
Rolling Pr420241966
Hazel Green420241966
River Falls420241998
Annaton420241998
Union Twp320241966
Wausaukee320231980
Washington I320241967
Esdaile320241966
Cochrane320231966
Cadott320241966

Brown Thrasher Population Trend in Other States

alabamaarkansascoloradoconnecticutdelawarefloridageorgiaillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomapennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasvermontvirginiawest-virginiawyoming

Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.