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

Song Sparrow Population Trend in New Jersey

All statesForest birds

Song Sparrow in New Jersey has edged up: up 13% on the route-weighted index since 1968.

+13%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 →
41Routes 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 Song Sparrow 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 Song Sparrow in New Jersey. See the full index history below.

Song Sparrow Population Forecast in New Jersey

If the recent trend holds, Song Sparrow in New Jersey is projected to stay roughly flat through 2030, near 14 (95% range 6.6–22). A 5-year backtest shows a typical error of ±6.3%, 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 →
14Projected 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 →
6.6–2295% 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 →
±6.3%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, Song Sparrow in New Jersey is projected to stay roughly flat through 2030, near 14 (95% range 6.6–22). A 5-year backtest shows a typical error of ±6.3%, 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 →
2026157.022
2027156.922
2028146.822
2029146.722
2030146.622

Song Sparrow Survey Routes in New Jersey

Routes recording Song Sparrow 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 →
Croton5320071970
Croton 24920252008
Bloomsbury4720251969
Hope4019941970
Clarksville3719911969
Ramseysburg2820251995
New Bedford2620241969
Dover2520231977
Sandbrook2420251969
Gillette2320251988
Ocean City2220251979
Cranbury2120251987
Bennett Mill 21920252016
Masonville1819701966
Midvale1720221967
Pottersville1720241977
Keyport1720221986
Bennett Mill1620001966
Pedricktown1420121991
Woodbury Hgt1320251967
Robbinsville1119791966
Kemah Lake1120241966
Deepwater1019771969
Toms River920241966
Holmansville920091969

Song Sparrow Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawaregeorgiaidahoillinoisindianaiowakansaskentuckymainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-mexiconew-yorknorth-carolinanorth-dakotaohiooregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseeutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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