BirdAnalyst
Species · BCR 22 · BBS 2026 Release · 1966–2025

Acadian Flycatcher In Eastern Tallgrass Prairie

All regionsEastern Tallgrass PrairieAerial insectivores

Acadian Flycatcher in Eastern Tallgrass Prairie has surged: up 146% on the route-weighted index since 1968.

+146%Since 1968TrendPercent 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 →
153Routes In RegionSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
59YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable SignalsNotable 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 Eastern Tallgrass Prairie: up 146% on the route-weighted index since 1968.

Acadian Flycatcher In Eastern Tallgrass Prairie Population Forecast

If the recent trend holds, Acadian Flycatcher in Eastern Tallgrass Prairie is projected to fall about 27% by 2030 — from 0.52 in 2025 to a central estimate of 0.38 (95% range 0.22–0.54). A 5-year backtest shows a typical error of ±48%, with 0% of held-out values landing inside the 95% band.

-27%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 →
0.38Projected 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 →
0.22–0.5495% 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 →
±48%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 Eastern Tallgrass Prairie is projected to fall about 27% by 2030 — from 0.52 in 2025 to a central estimate of 0.38 (95% range 0.22–0.54). A 5-year backtest shows a typical error of ±48%, with 0% of held-out values landing inside the 95% band.19662030
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 →
20260.360.200.52
20270.370.210.53
20280.370.210.53
20290.380.210.54
20300.380.220.54

Routes In Eastern Tallgrass Prairie

Routes recording Acadian Flycatcher in Eastern Tallgrass Prairie.
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 →
BelleviewILLINOIS242025
WallaceINDIANA102024
St MorganILLINOIS52022
MarshallILLINOIS52025
MoselleMISSOURI52025
BradburyILLINOIS42025
BrookvilleINDIANA42025
Witts StationINDIANA42025
MelroseIOWA41979
House SpringsMISSOURI42023
HarveysburgOHIO41996
Harveysburg 2OHIO42025
ChandlervillILLINOIS31972
Mascoutah LkILLINOIS32025
BeaucoupILLINOIS32025
FilleyMISSOURI32025
HuntsvilleMISSOURI32025
AuburnMISSOURI32025
AthensvilleILLINOIS22022
PawneeILLINOIS21978
ClarksdaleILLINOIS22021
ColumbiaILLINOIS22023
RobinsonILLINOIS22022
Camp PointILLINOIS22023
EldredILLINOIS22025

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