BirdAnalyst
Species · Arizona · BBS 2026 Release · 1966–2025

Spotted Towhee Population Trend in Arizona

All statesForest birds

Spotted Towhee in Arizona has surged: up 250% on the route-weighted index since 1970.

+250%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 →
43Routes 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 Spotted Towhee Trends in ArizonaNotable 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 →

Spotted Towhee has surged in Arizona: up 250% on the route-weighted index since 1970.

Spotted Towhee Population Forecast in Arizona

If the recent trend holds, Spotted Towhee in Arizona is projected to fall about 41% by 2030 — from 8.7 in 2025 to a central estimate of 5.1 (95% range 0.00–11). A 5-year backtest shows a typical error of ±28%, with 100% of held-out values landing inside the 95% band.

-41%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 →
5.1Projected 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 →
0.00–1195% 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 →
±28%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, Spotted Towhee in Arizona is projected to fall about 41% by 2030 — from 8.7 in 2025 to a central estimate of 5.1 (95% range 0.00–11). A 5-year backtest shows a typical error of ±28%, 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 →
20265.20.0011
20275.20.0011
20285.10.0011
20295.10.0011
20305.10.0011

Spotted Towhee Survey Routes in Arizona

Routes recording Spotted Towhee in Arizona.
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 →
Tonto Vill.9320251992
Sprucedale5420251992
Skull Valley 24820252025
Prescott3420251974
Forest Lakes3420251992
Aztec Peak3219781974
Skull Valley3120241996
Portal2520251975
Mt. Graham2220251995
Dragoon1320091993
Carr Mtn1320251985
Williams1220252001
Pinetop920221993
Rucker820091993
Zeniff819841968
Tsaile820231993
Mt Trumbull719801980
Round Rock519721969
Happy Jack520252025
Blue419911974
Patagonia420251968
Toroweap420251994
Cutter420001995
House Rock320221968
Black Mesa319951989

Spotted Towhee Population Trend in Other States

californiacoloradoidahokansasmontananebraskanevadanew-mexiconorth-dakotaoklahomaoregonsouth-dakotatexasutahwashingtonwyoming

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