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Species · California · BBS 2026 Release · 1966–2025

Green-tailed Towhee Population Trend in California

All statesForest birds

Green-tailed Towhee in California has surged: up 97% on the route-weighted index since 1970.

+97%Since 1970TrendPercent 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 →
85Routes 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 →
57YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Green-tailed Towhee Trends in CaliforniaNotable 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 →

Green-tailed Towhee has surged in California: up 97% on the route-weighted index since 1970.

Green-tailed Towhee Population Forecast in California

If the recent trend holds, Green-tailed Towhee in California is projected to rise about 11% by 2030 — from 2.6 in 2025 to a central estimate of 2.9 (95% range 1.9–3.9). A 5-year backtest shows a typical error of ±11.1%, with 100% of held-out values landing inside the 95% band.

+11%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 →
2.9Projected 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 →
1.9–3.995% 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 →
±11.1%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, Green-tailed Towhee in California is projected to rise about 11% by 2030 — from 2.6 in 2025 to a central estimate of 2.9 (95% range 1.9–3.9). A 5-year backtest shows a typical error of ±11.1%, with 100% 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 →
20262.81.83.9
20272.81.83.9
20282.91.83.9
20292.91.83.9
20302.91.93.9

Green-tailed Towhee Survey Routes in California

Routes recording Green-tailed Towhee in California.
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 →
Bodie9020251982
Big Bear4019861969
Crowley Lake3620251972
Valyermo3420191970
Deep Springs2720221972
Eagle Lake2420251969
Pine Mountain2220171997
Last Chance1920191993
Chilcoot1820241998
Little Truckee1520251997
Dardanelle1120191972
South Fork Mtn1120222000
Westville1020251971
Ship Mtn.1020161995
Pollock Pines1020251997
Crestview920251997
Johnsville820251975
Tionesta820211997
Benton720251973
Medicine Mtn.720152000
Macdoel619931976
Bridgeport619771973
Mt Shasta620191978
Cottage Spgs519681968
Green Valley520221970

Green-tailed Towhee Population Trend in Other States

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