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

Acadian Flycatcher Population Trend in Michigan

All statesAerial insectivores

Acadian Flycatcher in Michigan has surged: up 406% on the route-weighted index since 1969.

+406%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 →
36Routes 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 Acadian Flycatcher 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 →

Acadian Flycatcher has surged in Michigan: up 406% on the route-weighted index since 1969.

Acadian Flycatcher Population Forecast in Michigan

If the recent trend holds, Acadian Flycatcher in Michigan is projected to fall about 23% by 2029 — from 0.62 in 2024 to a central estimate of 0.48 (95% range 0.29–0.66). A 5-year backtest shows a typical error of ±18.8%, with 80% of held-out values landing inside the 95% band.

-23%Change by 2029TrendPercent 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 →
0.48Projected 2029 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.29–0.6695% 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 →
±18.8%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, Acadian Flycatcher in Michigan is projected to fall about 23% by 2029 — from 0.62 in 2024 to a central estimate of 0.48 (95% range 0.29–0.66). A 5-year backtest shows a typical error of ±18.8%, with 80% of held-out values landing inside the 95% band.19672029
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 →
20250.450.260.63
20260.450.270.64
20270.460.280.65
20280.470.280.65
20290.480.290.66

Acadian Flycatcher Survey Routes in Michigan

Routes recording Acadian Flycatcher 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 →
Nashville1120241968
Monterey1120241980
Almena620151994
New Buffalo520141992
Deckerville519841984
Belding 2320242008
Barry S.G.A.320121995
Barry S.G.A. 2320192013
Lawrence220221975
Bravo220221979
Juniata220092009
Pettysville219731973
Adair219911978
Hamburg 2120212017
Allegan Wma120191993
Scottville120222012
New Troy120211988
Lake City120082008
Big Rapids119871987
Galesburg120241978
Howardsville120241980
Remus120231992
Mottville120241967
Lapeer120192010
Rochester120232002

Acadian Flycatcher Population Trend in Other States

alabamaarkansasconnecticutdelawarefloridageorgiaillinoisindianaiowakansaskentuckylouisianamarylandmassachusettsminnesotamississippimissourinew-hampshirenew-jerseynew-yorknorth-carolinaohiooklahomapennsylvaniarhode-islandsouth-carolinatennesseetexasvirginiawest-virginiawisconsin

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