BirdAnalyst
Species · North Dakota · BBS 2026 Release · 1966–2025

Black-and-white Warbler Population Trend in North Dakota

All statesForest birds

Black-and-white Warbler in North Dakota has surged: up 819% on the route-weighted index since 1972.

+819%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 →
10Routes 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 →
47YearsYears 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-and-white Warbler Trends in North DakotaNotable 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 Black-and-white Warbler in North Dakota. See the full index history below.

Black-and-white Warbler Population Forecast in North Dakota

If the recent trend holds, Black-and-white Warbler in North Dakota is projected to fall about 20% by 2030 — from 0.37 in 2025 to a central estimate of 0.30 (95% range 0.10–0.49). A 5-year backtest shows a typical error of ±48.6%, with 40% of held-out values landing inside the 95% band.

-20%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 →
0.30Projected 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 →
0.10–0.4995% 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 →
±48.6%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, Black-and-white Warbler in North Dakota is projected to fall about 20% by 2030 — from 0.37 in 2025 to a central estimate of 0.30 (95% range 0.10–0.49). A 5-year backtest shows a typical error of ±48.6%, with 40% 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 →
20260.280.080.48
20270.280.090.48
20280.290.090.49
20290.290.090.49
20300.300.100.49

Black-and-white Warbler Survey Routes in North Dakota

Routes recording Black-and-white Warbler in North Dakota.
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 →
Turtle Mtns620251981
Roosevelt Pk320191982
Emerado220252005
Stanley220031972
Golva119991999
Cooperstown120252006
Regan119971997
Carpio120232023
Tobacco119961968
Denbigh120251971

Black-and-white Warbler Population Trend in Other States

alabamaarkansascaliforniaconnecticutdelawaregeorgiaillinoisindianakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourinebraskanew-hampshirenew-jerseynew-yorknorth-carolinaohiooklahomapennsylvaniarhode-islandsouth-carolinatennesseetexasvermontvirginiawest-virginiawisconsinwyoming

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