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Species · Michigan · BBS 2026 Release · 1966–2025

Pine Warbler Population Trend in Michigan

All statesForest birds

Pine Warbler in Michigan has surged: up 45× on the route-weighted index since 1969.

45×Since 1969TrendPercent 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 →
78Routes 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 →
54YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Pine 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 →

Pine Warbler has surged in Michigan: up 45× on the route-weighted index since 1969.

Pine Warbler Population Forecast in Michigan

If the recent trend holds, Pine Warbler in Michigan is projected to stay roughly flat through 2030, near 3.0 (95% range 2.0–3.9). A 5-year backtest shows a typical error of ±18.3%, with 100% of held-out values landing inside the 95% band.

-1%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 →
3.0Projected 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 →
2.0–3.995% 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 →
±18.3%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, Pine Warbler in Michigan is projected to stay roughly flat through 2030, near 3.0 (95% range 2.0–3.9). A 5-year backtest shows a typical error of ±18.3%, with 100% of held-out values landing inside the 95% band.19672030
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 →
20262.81.83.7
20272.81.93.8
20282.91.93.8
20292.92.03.8
20303.02.03.9

Pine Warbler Survey Routes in Michigan

Routes recording Pine 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 →
Seney Nwr1620251992
Betchler Lks1420251992
Muskallonge1220241968
Red Oak1220221985
Cluster Lakes1220102006
Imp Lake1120191992
Big Island Lake1120102008
Gooseneck1020102008
Gibbs City920251985
Sand Lake920251978
Irons819891989
Ned Lake720251999
Tahquamenon720251976
Hungerford720251995
Walloon Lake 2720242005
Mayfield720252001
Ensign720102006
Frederic620011971
Harrietta620251990
Crystal Fls520251988
Creighton520251978
Scottville520251975
Gilchrist520211987
Skegemog Pt520251975
Herman420221983

Pine Warbler Population Trend in Other States

alabamaarkansasconnecticutdelawarefloridageorgiaillinoisindianakentuckylouisianamainemarylandmassachusettsminnesotamississippimissourinew-hampshirenew-jerseynew-yorknorth-carolinaohiooklahomapennsylvaniarhode-islandsouth-carolinatennesseetexasvermontvirginiawest-virginiawisconsin

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