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Species · Wisconsin · BBS 2025 Release · 1966–2024

Cape May Warbler Population Trend in Wisconsin

All statesForest birds

Cape May Warbler in Wisconsin has surged: up 342% on the route-weighted index since 1974.

+342%Since 1974
23Routes In State
50Years

Notable Cape May Warbler Trends in Wisconsin

long arc increasecomputed index

Cape May Warbler has surged in Wisconsin: up 342% on the route-weighted index since 1974.

Cape May Warbler Population Forecast in Wisconsin

If the recent trend holds, Cape May Warbler in Wisconsin is projected to rise about 29% by 2029 — from 0.06 in 2024 to a central estimate of 0.08 (95% range 0.00–0.16). A 5-year backtest shows a typical error of ±38.2%, with 80% of held-out values landing inside the 95% band.

+29%Change by 2029
0.08Projected 2029 index
0.00–0.1695% range
±38.2%Backtest error
19712029
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
20250.080.000.15
20260.080.000.16
20270.080.000.16
20280.080.000.16
20290.080.000.16

Cape May Warbler Survey Routes in Wisconsin

Routes recording Cape May Warbler in Wisconsin.
Eagle River620221975
Shanagolden420221975
Land O Lakes420161981
Popple River320241973
Minong219971971
Montreal219871979
Chaffey119971996
Iron River120182005
Grand View120101974
Bayfield119871971
Cumberland119981998
Couderay119841984
Phillips120071988
Merrill119911990
Mcnaughton120222008
Crandon120061976
Amberg120242013
Wausaukee120192019
Stevens Pt120162016
Oconto Falls120162016
Rhinelander120232009
Cavour120241998
Land O' Lakes 2120232019

Cape May Warbler Population Trend in Other States

mainemichiganminnesotanew-hampshirenew-yorkvermont

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