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Species · Michigan · BBS 2025 Release · 1966–2024

Prothonotary Warbler Population Trend in Michigan

All statesForest birds

Prothonotary Warbler in Michigan has held roughly steady: down 2% on the route-weighted index since 1982.

-2%Since 1982TrendPercent 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 →
11Routes 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 →
40YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Prothonotary 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 →

No notable trend signals for Prothonotary Warbler in Michigan. See the full index history below.

Prothonotary Warbler Population Forecast in Michigan

If the recent trend holds, Prothonotary Warbler in Michigan is projected to stay roughly flat through 2028, near 0.03 (95% range 0.00–0.07). A 5-year backtest shows a typical error of ±70.7%, with 100% of held-out values landing inside the 95% band.

n/aChange by 2028TrendPercent 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 →
0.03Projected 2028 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.0795% 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 →
±70.7%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, Prothonotary Warbler in Michigan is projected to stay roughly flat through 2028, near 0.03 (95% range 0.00–0.07). A 5-year backtest shows a typical error of ±70.7%, with 100% of held-out values landing inside the 95% band.19802028
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 →
20240.030.000.07
20250.030.000.07
20260.030.000.07
20270.030.000.07
20280.030.000.07

Prothonotary Warbler Survey Routes in Michigan

Routes recording Prothonotary 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 →
Rochester220162016
Homer220211991
Nashville119961996
Coopersville120061999
Belding120021984
Monterey120151985
Belding 2120062006
Mottville120231980
New Buffalo120011997
Almena120131993
Prattville120112010

Prothonotary Warbler Population Trend in Other States

alabamaarkansasdelawarefloridageorgiaillinoisindianaiowakansaskentuckylouisianamarylandminnesotamississippimissourinew-jerseynew-yorknorth-carolinaohiooklahomapennsylvaniasouth-carolinatennesseetexasvirginiawest-virginiawisconsin

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