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Species · Michigan · BBS 2026 Release · 1966–2025

Blue-winged Warbler Population Trend in Michigan

All statesForest birds

Blue-winged Warbler in Michigan has surged: up 449% on the route-weighted index since 1971.

+449%Since 1971TrendPercent change in the route-weighted abundance index between a smoothed baseline window and the most recent one. It tracks direction, not absolute population.Full methodology →
50Routes In StateSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
56YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Blue-winged Warbler Trends in MichiganNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

long arc increasecomputed indexTrend sourceWhether the figure is our own computed route-weighted index or an official USGS modeled estimate. The current build labels every trend as computed.Full methodology →

Blue-winged Warbler has surged in Michigan: up 449% on the route-weighted index since 1971.

Blue-winged Warbler Population Forecast in Michigan

If the recent trend holds, Blue-winged Warbler in Michigan is projected to rise about 20% by 2030 — from 0.41 in 2025 to a central estimate of 0.49 (95% range 0.07–0.91). A 5-year backtest shows a typical error of ±78.1%, with 100% of held-out values landing inside the 95% band.

+20%Change by 2030TrendPercent change in the route-weighted abundance index between a smoothed baseline window and the most recent one. It tracks direction, not absolute population.Full methodology →
0.49Projected 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.07–0.9195% range95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →
±78.1%Backtest errorBacktest errorTypical error when we hold out the most recent years, forecast them, and compare to what actually happened. Lower means a more trustworthy projection.Full methodology →
If the recent trend holds, Blue-winged Warbler in Michigan is projected to rise about 20% by 2030 — from 0.41 in 2025 to a central estimate of 0.49 (95% range 0.07–0.91). A 5-year backtest shows a typical error of ±78.1%, with 100% of held-out values landing inside the 95% band.19692030
Projection of the recent trend (dashed) with 80/95% bands — a projection, not a prediction. Habitat, climate, and land use are not modeled.
YearProjected indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →95% low95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →95% high95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →
20260.480.060.90
20270.480.070.90
20280.490.070.91
20290.490.070.91
20300.490.070.91

Blue-winged Warbler Survey Routes in Michigan

Routes recording Blue-winged Warbler in Michigan.
Recent countThe raw number of individuals recorded on this route in its most recent survey year. A single-route tally, not a trend.Full methodology →
Barry S.G.A.620121995
Monterey520251978
Almena420141993
Chippewa Lk.320231992
Bravo320231974
Nashville320251969
Remus320251975
Richmond320101999
Belding 2220182007
Scottville220251973
Lawrence220041974
Rochester220251993
Walloon Lake219801980
Fowlerville219941983
Harrietta120051994
Marenisco120052005
Hungerford120251992
New Buffalo120111992
Hamburg 2120212006
Allegan Wma120191993
Cunard120212014
Bear Lake120251997
Big Blue Lk120242023
New Troy119991999
Barry S.G.A. 2120172013

Blue-winged Warbler Population Trend in Other States

alabamaarkansasconnecticutdelawaregeorgiaillinoisindianaiowakentuckymarylandmassachusettsminnesotamississippimissourinew-hampshirenew-jerseynew-yorknorth-carolinaohiooklahomapennsylvaniarhode-islandtennesseevermontvirginiawest-virginiawisconsin

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.