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

Carolina Wren Population Trend in New Jersey

All statesForest birds

Carolina Wren in New Jersey has surged: up 54× on the route-weighted index since 1968.

54×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 Carolina 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 →

Carolina Wren has surged in New Jersey: up 54× on the route-weighted index since 1968.

Carolina Wren Population Forecast in New Jersey

If the recent trend holds, Carolina Wren in New Jersey is projected to stay roughly flat through 2030, near 14 (95% range 9.2–18). A 5-year backtest shows a typical error of ±26.8%, with 60% of held-out values landing inside the 95% band.

-4%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 →
9.2–1895% 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 →
±26.8%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, Carolina Wren in New Jersey is projected to stay roughly flat through 2030, near 14 (95% range 9.2–18). A 5-year backtest shows a typical error of ±26.8%, with 60% 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 →
2026138.117
2027138.418
2028138.718
2029148.918
2030149.218

Carolina Wren Survey Routes in New Jersey

Routes recording Carolina 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 →
Cape May Ch6220131992
Pedricktown 24720252013
Pedricktown2920121991
Croton 22620252008
Sandbrook2520251974
Ramseysburg2420251995
Greenwich2320251968
Kemah Lake2320241986
Woodbury Hgt2220251968
Del Haven1919911991
New Bedford1920241969
Bennett Mill 21920252016
Dover1620231990
Roosevelt1420221986
Croton1320071975
Albion1220221966
Gillette1220251991
Six Points1120251980
Holmansville1120091971
Estell Manor1120252021
Pomona1020251978
Bloomsbury920251976
Keyport920221990
Deepwater619761969
Toms River620241976

Carolina Wren Population Trend in Other States

alabamaarkansasconnecticutdelawarefloridageorgiaillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourinebraskanew-hampshirenew-yorknorth-carolinaohiooklahomapennsylvaniarhode-islandsouth-carolinatennesseetexasvermontvirginiawest-virginiawisconsin

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