BirdAnalyst
Species · BCR 30 · BBS 2025 Release · 1966–2024

Acadian Flycatcher In New England / Mid-Atlantic Coast

All regionsNew England / Mid-Atlantic CoastAerial insectivores

Acadian Flycatcher in New England / Mid-Atlantic Coast 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 →
108Routes 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 →
58YearsYears 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 New England / Mid-Atlantic Coast: up 146% on the route-weighted index since 1968.

Acadian Flycatcher In New England / Mid-Atlantic Coast Population Forecast

If the recent trend holds, Acadian Flycatcher in New England / Mid-Atlantic Coast is projected to stay roughly flat through 2029, near 4.6 (95% range 3.7–5.5). A 5-year backtest shows a typical error of ±11.5%, with 100% of held-out values landing inside the 95% band.

-8%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 →
4.6Projected 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 →
3.7–5.595% 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 →
±11.5%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 New England / Mid-Atlantic Coast is projected to stay roughly flat through 2029, near 4.6 (95% range 3.7–5.5). A 5-year backtest shows a typical error of ±11.5%, with 100% of held-out values landing inside the 95% band.19662029
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 →
20254.43.55.3
20264.43.65.3
20274.53.65.4
20284.63.75.4
20294.63.75.5

Routes In New England / Mid-Atlantic Coast

Routes recording Acadian Flycatcher in New England / Mid-Atlantic Coast.
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 →
Island CreekMARYLAND672024
PomonkeyMARYLAND552024
BrandonVIRGINIA282024
HughesvilleMARYLAND242024
WalkersVIRGINIA222023
DavidsnvilleMARYLAND192024
Port RoyalVIRGINIA182019
La PlataMARYLAND172009
White StoneVIRGINIA162024
TruhartVIRGINIA162024
PomfretMARYLAND152024
MillingtonMARYLAND152024
Forest GroveMARYLAND142023
Pr FrederickMARYLAND132024
Pt RepublicMARYLAND121989
GloucesterVIRGINIA122024
Milton 2DELAWARE112017
Furnace TownMARYLAND112024
Tall TimbersMARYLAND102014
NottinghamMARYLAND102024
St. George'S IslandMARYLAND92017
MillsboroDELAWARE72024
PepperboxDELAWARE72016
CheltenhamMARYLAND72004
Broomes IslMARYLAND71996

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