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

Chimney Swift Population Trend in New Jersey

All statesAerial insectivores

Chimney Swift in New Jersey has edged down: down 17% on the route-weighted index since 1968.

-17%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 Chimney Swift 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 Chimney Swift in New Jersey. See the full index history below.

Chimney Swift Population Forecast in New Jersey

If the recent trend holds, Chimney Swift in New Jersey is projected to stay roughly flat through 2030, near 5.8 (95% range 2.4–9.1). A 5-year backtest shows a typical error of ±16.5%, with 100% of held-out values landing inside the 95% band.

+5%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 →
5.8Projected 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 →
2.4–9.195% 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 →
±16.5%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, Chimney Swift in New Jersey is projected to stay roughly flat through 2030, near 5.8 (95% range 2.4–9.1). A 5-year backtest shows a typical error of ±16.5%, 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 →
20265.92.69.3
20275.92.69.2
20285.82.59.2
20295.82.59.1
20305.82.49.1

Chimney Swift Survey Routes in New Jersey

Routes recording Chimney Swift 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 →
Deepwater4319771969
Hope3919941970
Bloomsbury3620251969
Del Haven3119911991
Midvale2920221967
Pedricktown2720121991
Cape May Ch1820131992
Dover1220231977
Croton1120071970
Mt Misery1119881976
Sandbrook1020251969
Keyport1020221990
Ramseysburg1020251995
Woodbury Hgt820251967
Albion820221966
Croton 2820252008
Greenwich720251966
Pedricktown 2720242013
Bennett Mill 2720252016
Kemah Lake620241966
Gillette520251988
Toms River420241966
Masonville419701966
Holmansville420091969
Clarksville419911969

Chimney Swift Population Trend in Other States

alabamaarkansascoloradoconnecticutdelawarefloridageorgiaillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanew-hampshirenew-yorknorth-carolinanorth-dakotaohiooklahomapennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasvermontvirginiawest-virginiawisconsinwyoming

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