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Species · North Carolina · BBS 2025 Release · 1966–2024

Blackburnian Warbler Population Trend in North Carolina

All statesForest birds

Blackburnian Warbler in North Carolina has surged: up 95% on the route-weighted index since 1974.

+95%Since 1974TrendPercent 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 →
16Routes 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 →
42YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Blackburnian 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 →

Blackburnian Warbler has surged in North Carolina: up 95% on the route-weighted index since 1974.

Blackburnian Warbler Population Forecast in North Carolina

If the recent trend holds, Blackburnian Warbler in North Carolina is projected to rise about 23% by 2029 — from 0.14 in 2024 to a central estimate of 0.18 (95% range 0.00–0.48). A 5-year backtest shows a typical error of ±55.3%, with 100% of held-out values landing inside the 95% band.

+23%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 →
0.18Projected 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 →
0.00–0.4895% 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 →
±55.3%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, Blackburnian Warbler in North Carolina is projected to rise about 23% by 2029 — from 0.14 in 2024 to a central estimate of 0.18 (95% range 0.00–0.48). A 5-year backtest shows a typical error of ±55.3%, with 100% of held-out values landing inside the 95% band.19692029
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 →
20250.170.000.48
20260.170.000.48
20270.180.000.48
20280.180.000.48
20290.180.000.48

Blackburnian Warbler Survey Routes in North Carolina

Routes recording Blackburnian 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 →
Busick2519961994
Oteen720232001
French Broad River620242001
Linville420211979
N. Mills Riv319951994
Cullowhee320231974
Waterville220241994
Cherokee220242011
Highlands120231994
Kyle120211994
Andrews119981994
Pinelog120042004
Brevard120212021
Fontana120131969
Flay119971997
Marshall120222015

Blackburnian Warbler Population Trend in Other States

connecticutgeorgiaindianamainemarylandmassachusettsmichiganminnesotanew-hampshirenew-jerseynew-yorkohiopennsylvaniarhode-islandtennesseevermontvirginiawest-virginiawisconsin

Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.