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Species · BCR 14 · BBS 2025 Release · 1966–2024

Barn Swallow In Atlantic Northern Forest

All regionsAtlantic Northern ForestAerial insectivores

Barn Swallow in Atlantic Northern Forest has collapsed: down 83% on the route-weighted index since 1968.

-83%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 →
150Routes 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 declinecomputed 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 →

Barn Swallow has collapsed in Atlantic Northern Forest: down 83% on the route-weighted index since 1968.

Barn Swallow In Atlantic Northern Forest Population Forecast

If the recent trend holds, Barn Swallow in Atlantic Northern Forest is projected to fall about 100% by 2029 — from 5.6 in 2024 to a central estimate of 0.00 (95% range 0.00–7.0). A 5-year backtest shows a typical error of ±185.2%, with 20% of held-out values landing inside the 95% band.

-100%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 →
0.00Projected 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 →
0.00–7.095% 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 →
±185.2%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, Barn Swallow in Atlantic Northern Forest is projected to fall about 100% by 2029 — from 5.6 in 2024 to a central estimate of 0.00 (95% range 0.00–7.0). A 5-year backtest shows a typical error of ±185.2%, with 20% 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 →
20250.000.007.0
20260.000.007.0
20270.000.007.0
20280.000.007.0
20290.000.007.0

Routes In Atlantic Northern Forest

Routes recording Barn Swallow in Atlantic Northern Forest.
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 →
Forest StaMAINE482000
WatervilleVERMONT421980
NorthfieldMAINE311981
Crawford NotNEW-HAMPSHIRE311975
BentonMAINE271980
PittsfieldMASSACHUSETTS232016
FitzwilliamNEW-HAMPSHIRE212024
WalpoleNEW-HAMPSHIRE202024
HighmarketNEW-YORK182024
St JohnsburyVERMONT182024
CanterburyNEW-HAMPSHIRE172024
PetersburgNEW-YORK172018
Cummington 2MASSACHUSETTS162024
New HartfordCONNECTICUT151987
CharlestonMAINE152018
JeffersonMAINE152010
BrownfieldMAINE152009
TopsfieldMAINE141996
Tupper LakeNEW-YORK141976
StacyvilleMAINE132024
ChesterfieldMASSACHUSETTS132024
CornvilleMAINE122024
PeterboroughNEW-HAMPSHIRE122024
Number FourNEW-YORK122016
HardwickVERMONT122024

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