BirdAnalyst
Species · BBS 2026 Release · 1966–2025

Brown-headed Nuthatch Population Analysis

SittidaeForest birdsSitta pusilla

Brown-headed Nuthatch has edged up: up 17% on the route-weighted index since 1968.

+17%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 →
612RoutesSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
59Years SurveyedYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

About the Brown-headed Nuthatch

The Brown-headed Nuthatch (Sitta pusilla) is a North American member of the Nuthatches (Sittidae). In this analysis it is grouped with the forest birds.

Size
4–7 in long (10–18 cm) — a small tree-climbing songbird (typical for the family)
Habitat
Woodlands and forest edges, including wooded suburbs and parks.
Diet
Insects and spiders gleaned from foliage and bark, with seeds and berries in season.
Range
Recorded on 612 Breeding Bird Survey routes across 14 states, most concentrated in the Southeastern Coastal Plain.
Family
Sittidae · Forest birds

Notable Brown-headed Nuthatch TrendsNotable 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 Brown-headed Nuthatch. See the full index history below.

Brown-headed Nuthatch Population Forecast

If the recent trend holds, Brown-headed Nuthatch is projected to stay roughly flat through 2030, near 0.36 (95% range 0.27–0.46). A 5-year backtest shows a typical error of ±12.8%, with 100% of held-out values landing inside the 95% band.

-8%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 →
0.36Projected 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 →
0.27–0.4695% 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 →
±12.8%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, Brown-headed Nuthatch is projected to stay roughly flat through 2030, near 0.36 (95% range 0.27–0.46). A 5-year backtest shows a typical error of ±12.8%, 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 →
20260.360.260.45
20270.360.260.45
20280.360.270.45
20290.360.270.45
20300.360.270.46

Where the Brown-headed Nuthatch Is Detected

BBS routes recording Brown-headed Nuthatch, sized by most recent count.

Brown-headed Nuthatch Population Trend by State

Brown-headed Nuthatch population trend by state.
TrendPercent 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 →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
Alabama-7%196893
Arkansas-33%197025
Delaware+363%19786
Florida+39%196869
Georgia+16%1968110
Louisiana-64%196952
Maryland+496%196812
Mississippi+105%196845
North Carolina+130%196889
Oklahoma+251%19719
South Carolina+24%196849
Tennessee+169%19948
Texas+6%197026
Virginia+85%196819

Brown-headed Nuthatch Population Trend by Region

Bird Conservation Regions are the ecological unit for trends.

Brown-headed Nuthatch population trend by Bird Conservation Region.
TrendPercent 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 →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
West Gulf Coastal Plain / Ouachitas-20%196996
Southeastern Coastal Plain+65%1968302
Appalachian Mountains-18%196847
Piedmont+174%1968106
New England / Mid-Atlantic Coast+442%196822
Peninsular Florida-25%196828

Brown-headed Nuthatch Conservation Status

Our route-weighted index shows it up about 17% since 1968.

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14. Trend is a route-weighted relative-abundance index, not an absolute population.