BirdAnalyst
Species · New Jersey · BBS 2026 Release · 1966–2025

Barn Swallow Population Trend in New Jersey

All statesAerial insectivores

Barn Swallow in New Jersey has edged down: down 18% on the route-weighted index since 1968.

-18%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 →
42Routes 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 →
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 Barn Swallow Trends in New JerseyNotable 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 Jersey. See the full index history below.

Barn Swallow Population Forecast in New Jersey

If the recent trend holds, Barn Swallow in New Jersey is projected to stay roughly flat through 2030, near 9.8 (95% range 5.3–14). A 5-year backtest shows a typical error of ±9.7%, with 100% of held-out values landing inside the 95% band.

+0%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 →
9.8Projected 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 →
5.3–1495% 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 →
±9.7%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 Jersey is projected to stay roughly flat through 2030, near 9.8 (95% range 5.3–14). A 5-year backtest shows a typical error of ±9.7%, 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 →
2026105.615
2027105.515
202810.05.514
20299.95.414
20309.85.314

Barn Swallow Survey Routes in New Jersey

Routes recording Barn Swallow in New Jersey.
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 →
Woodbury Hgt4320251967
Clarksville3719911969
Deepwater3519771969
Pedricktown 22920252013
Keyport2520221986
Cape May Ch2420131992
Pedricktown2220121991
Hope1719941970
Ocean City1620251979
Mt Misery1619891976
Six Points1520251978
Masonville1519701966
Bennett Mill 21520252016
Kemah Lake1420241966
Dover1420231977
Roosevelt1420221986
Villas1319811979
High Point1120251977
Del Haven1019911991
Greenwich920251966
Croton920031970
Winslow820251989
Gillette720251988
Pottersville620241977
Pomona620251978

Barn Swallow Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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