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

Prairie Warbler Population Trend in New Jersey

All statesForest birds

Prairie Warbler in New Jersey has declined: down 50% on the route-weighted index since 1968.

-50%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 →
34Routes 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 Prairie Warbler 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 Prairie Warbler in New Jersey. See the full index history below.

Prairie Warbler Population Forecast in New Jersey

If the recent trend holds, Prairie Warbler in New Jersey is projected to fall about 72% by 2030 — from 3.4 in 2025 to a central estimate of 0.94 (95% range 0.00–5.4). A 5-year backtest shows a typical error of ±61.1%, with 100% of held-out values landing inside the 95% band.

-72%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 →
0.94Projected 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 →
0.00–5.495% 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 →
±61.1%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, Prairie Warbler in New Jersey is projected to fall about 72% by 2030 — from 3.4 in 2025 to a central estimate of 0.94 (95% range 0.00–5.4). A 5-year backtest shows a typical error of ±61.1%, 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 →
20261.20.005.7
20271.20.005.6
20281.10.005.5
20291.00.005.4
20300.940.005.4

Prairie Warbler Survey Routes in New Jersey

Routes recording Prairie Warbler 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 →
Spraguetown 33020252023
Pomona1520251978
Toms River1220241966
Bennett Mill1120001966
Friendship820251977
Estell Manor420222022
Del Haven319911991
Ancora319771966
Holmansville320091969
Pottersville320161979
Albion220221966
Gillette220241989
Winslow220251989
Bennett Mill 2220252016
Woodbury Hgt119911986
Greenwich120251966
Six Points120251978
Spraguetown 2120122000
Sandbrook120251972
New Bedford119981969
Croton119741974
Hope119941977
Midvale120142002
Kemah Lake120221969
Bloomsbury120221990

Prairie Warbler Population Trend in Other States

alabamaarkansascaliforniaconnecticutdelawarefloridageorgiaillinoisindianakentuckylouisianamainemarylandmassachusettsmichiganmississippimissourinew-hampshirenew-yorknorth-carolinaohiooklahomapennsylvaniarhode-islandsouth-carolinatennesseetexasvermontvirginiawest-virginiawisconsin

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