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Species · Delaware · BBS 2025 Release · 1966–2024

White-breasted Nuthatch Population Trend in Delaware

All statesForest birds

White-breasted Nuthatch in Delaware has surged: up 608% on the route-weighted index since 1979.

+608%Since 1979TrendPercent 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 →
22YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable White-breasted Nuthatch Trends in DelawareNotable 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 →

White-breasted Nuthatch has surged in Delaware: up 608% on the route-weighted index since 1979.

White-breasted Nuthatch Population Forecast in Delaware

If the recent trend holds, White-breasted Nuthatch in Delaware is projected to stay roughly flat through 2029, near 0.59 (95% range 0.01–1.2). A 5-year backtest shows a typical error of ±84.8%, with 80% of held-out values landing inside the 95% band.

-2%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 →
0.59Projected 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 →
0.01–1.295% 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 →
±84.8%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, White-breasted Nuthatch in Delaware is projected to stay roughly flat through 2029, near 0.59 (95% range 0.01–1.2). A 5-year backtest shows a typical error of ±84.8%, with 80% of held-out values landing inside the 95% band.19722029
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 →
20250.550.001.1
20260.560.001.1
20270.570.001.1
20280.580.001.2
20290.590.011.2

White-breasted Nuthatch Survey Routes in Delaware

Routes recording White-breasted Nuthatch in Delaware.
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 →
Mt Pleasant220112006
Harrington220241979
Millsboro220232021
Milton 2220172017
Wilmington120142003
Frederica120141973
Frankford119911991
Holleyville120031972
Blackbird120242005
Georgetown120102010

White-breasted Nuthatch Population Trend in Other States

alabamaarizonaarkansascaliforniacoloradoconnecticutfloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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