BirdAnalyst
Species · New Jersey · BBS 2025 Release · 1966–2024

Song Sparrow Population Trend in New Jersey

All statesGeneralists

Song Sparrow in New Jersey has edged up: up 16% on the route-weighted index since 1968.

+16%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 →
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 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 fall about 13% by 2029 — from 16 in 2024 to a central estimate of 14 (95% range 6.6–22). A 5-year backtest shows a typical error of ±7.2%, with 100% of held-out values landing inside the 95% band.

-13%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 →
14Projected 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 →
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 →
±7.2%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, Song Sparrow in New Jersey is projected to fall about 13% by 2029 — from 16 in 2024 to a central estimate of 14 (95% range 6.6–22). A 5-year backtest shows a typical error of ±7.2%, with 100% 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 →
2025157.122
2026156.922
2027156.822
2028146.722
2029146.622

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 25320242008
Hope4019941970
Clarksville3719911969
Cranbury3120241987
Sandbrook3020241969
Bloomsbury3020241969
Ocean City2720241979
New Bedford2620241969
Dover2520231977
Gillette2520241988
Ramseysburg2520241995
Bennett Mill 21920242016
Masonville1819701966
Midvale1720221967
Pottersville1720241977
Keyport1720221986
Bennett Mill1620001966
High Point1420241977
Pedricktown1420121991
Woodbury Hgt1320241967
Robbinsville1119791966
Kemah Lake1120241966
Deepwater1019771969
Toms River920241966

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 2026-05-22.