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

Northern House Wren Population Trend in New Jersey

All statesForest birds

Northern House Wren in New Jersey has risen sharply: up 55% on the route-weighted index since 1968.

+55%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 →
44Routes 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 Northern House Wren 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 →

long arc increasecomputed indexTrend sourceWhether the figure is our own computed route-weighted index or an official USGS modeled estimate. The current build labels every trend as computed.Full methodology →

Northern House Wren has risen sharply in New Jersey: up 55% on the route-weighted index since 1968.

Northern House Wren Population Forecast in New Jersey

If the recent trend holds, Northern House Wren in New Jersey is projected to rise about 33% by 2030 — from 9.3 in 2025 to a central estimate of 12 (95% range 8.9–16). A 5-year backtest shows a typical error of ±11.6%, with 100% of held-out values landing inside the 95% band.

+33%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 →
12Projected 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 →
8.9–1695% 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 →
±11.6%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, Northern House Wren in New Jersey is projected to rise about 33% by 2030 — from 9.3 in 2025 to a central estimate of 12 (95% range 8.9–16). A 5-year backtest shows a typical error of ±11.6%, 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 →
2026128.716
2027128.816
2028128.816
2029128.816
2030128.916

Northern House Wren Survey Routes in New Jersey

Routes recording Northern House Wren 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 →
Croton 23220252008
Dover2520231977
Kemah Lake2220241966
Gillette2120251988
Ramseysburg2120251995
Sandbrook2020251969
Albion1920221966
Holmansville1920091969
Keyport1620221986
Hope1519941970
Bloomsbury1120251969
New Bedford920241969
Croton920071970
Bennett Mill 2920252016
High Point820251977
Cranbury820251987
Del Haven819911991
Winslow820251989
Clarksville719911969
Pomona720251978
Pedricktown720121991
Spraguetown 3620252023
Woodbury Hgt520251967
Deepwater519771970
Villas519811979

Northern House Wren Population Trend in Other States

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

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