BirdAnalyst
Species · BCR 30 · BBS 2026 Release · 1966–2025

Barn Swallow In New England / Mid-Atlantic Coast

All regionsNew England / Mid-Atlantic CoastAerial insectivores

Barn Swallow in New England / Mid-Atlantic Coast has declined: down 34% on the route-weighted index since 1968.

-34%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 →
163Routes 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 →

No notable trend signals for Barn Swallow in New England / Mid-Atlantic Coast. See the full index history below.

Barn Swallow In New England / Mid-Atlantic Coast Population Forecast

If the recent trend holds, Barn Swallow in New England / Mid-Atlantic Coast is projected to stay roughly flat through 2030, near 11 (95% range 7.5–14). A 5-year backtest shows a typical error of ±7.7%, with 100% of held-out values landing inside the 95% band.

-3%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 →
11Projected 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 →
7.5–1495% 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 →
±7.7%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 New England / Mid-Atlantic Coast is projected to stay roughly flat through 2030, near 11 (95% range 7.5–14). A 5-year backtest shows a typical error of ±7.7%, with 100% 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 →
2026117.914
2027117.814
2028117.714
2029117.614
2030117.514

Routes In New England / Mid-Atlantic Coast

Routes recording Barn Swallow 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 →
HarmonyMARYLAND982017
HarringtonDELAWARE672025
CokesburyMARYLAND602025
Snow HillMARYLAND491976
UncasvilleCONNECTICUT462025
MysticCONNECTICUT452023
Bethany BchDELAWARE441990
Woodbury HgtNEW-JERSEY432025
DoverDELAWARE381987
FrankfordDELAWARE372012
ClarksvilleNEW-JERSEY371991
MardelaMARYLAND352019
DeepwaterNEW-JERSEY351977
WestbrookCONNECTICUT332025
SinepuxentMARYLAND331978
Holleyville 2DELAWARE312024
HongaMARYLAND302025
BlackbirdDELAWARE292025
Pedricktown 2NEW-JERSEY292025
HolleyvilleDELAWARE272004
MiltonDELAWARE262016
KeyportNEW-JERSEY252022
MelitotaMARYLAND242025
MatthewsMARYLAND242025
Cape May ChNEW-JERSEY242013

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