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Species · North Carolina · BBS 2026 Release · 1966–2025

Black-throated Green Warbler Population Trend in North Carolina

All statesForest birds

Black-throated Green Warbler in North Carolina has surged: up 540% on the route-weighted index since 1972.

+540%Since 1972TrendPercent 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 →
30Routes 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 →
53YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Black-throated Green Warbler Trends in North CarolinaNotable 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 →

Black-throated Green Warbler has surged in North Carolina: up 540% on the route-weighted index since 1972.

Black-throated Green Warbler Population Forecast in North Carolina

If the recent trend holds, Black-throated Green Warbler in North Carolina is projected to rise about 32% by 2030 — from 1.7 in 2025 to a central estimate of 2.2 (95% range 1.2–3.2). A 5-year backtest shows a typical error of ±55.7%, with 80% of held-out values landing inside the 95% band.

+32%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 →
2.2Projected 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 →
1.2–3.295% 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 →
±55.7%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, Black-throated Green Warbler in North Carolina is projected to rise about 32% by 2030 — from 1.7 in 2025 to a central estimate of 2.2 (95% range 1.2–3.2). A 5-year backtest shows a typical error of ±55.7%, with 80% of held-out values landing inside the 95% band.19682030
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 →
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Black-throated Green Warbler Survey Routes in North Carolina

Routes recording Black-throated Green Warbler in North Carolina.
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 →
Fontana2920251968
Highlands2820251994
Table Rock2420221994
French Broad River2320252001
N. Mills Riv1219951994
Waterville820251994
Busick620021994
Linville420251976
Cherokee320252013
Cullowhee320251995
Hendersonvil320252001
Murphy320211996
Oteen320241984
Mashoes219821973
Brevard220251975
Marshall220242013
Shallotte119841984
Arapahoe119921968
Beargrass119811981
Broad Creek120152010
Kinston119811981
Kyle120241995
Andrews119981994
Pinelog120122001
Newport120052005

Black-throated Green Warbler Population Trend in Other States

alabamaarkansasconnecticutgeorgiaindianakentuckymainemarylandmassachusettsmichiganminnesotamissourinew-hampshirenew-jerseynew-yorkohiooklahomapennsylvaniarhode-islandsouth-carolinatennesseevermontvirginiawest-virginiawisconsin

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