BirdAnalyst
Species · Idaho · BBS 2025 Release · 1966–2024

Green-tailed Towhee Population Trend in Idaho

All statesGeneralists

Green-tailed Towhee in Idaho has surged: up 213% on the route-weighted index since 1971.

+213%Since 1971TrendPercent 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 →
25Routes 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 →
55YearsYears 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 IdahoNotable 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 Idaho: up 213% on the route-weighted index since 1971.

Green-tailed Towhee Population Forecast in Idaho

If the recent trend holds, Green-tailed Towhee in Idaho is projected to fall about 15% by 2029 — from 1.6 in 2024 to a central estimate of 1.4 (95% range 0.66–2.1). A 5-year backtest shows a typical error of ±20%, with 100% of held-out values landing inside the 95% band.

-15%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 →
1.4Projected 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 →
0.66–2.195% 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 →
±20%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 Idaho is projected to fall about 15% by 2029 — from 1.6 in 2024 to a central estimate of 1.4 (95% range 0.66–2.1). A 5-year backtest shows a typical error of ±20%, with 100% of held-out values landing inside the 95% band.19682029
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 →
20251.30.612.1
20261.40.622.1
20271.40.642.1
20281.40.652.1
20291.40.662.1

Green-tailed Towhee Survey Routes in Idaho

Routes recording Green-tailed Towhee in Idaho.
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 →
Magic Mtn1620241989
Silver City1520241993
Alturas619681968
Almo620231988
Challis420191994
Henry419831973
Baker320241990
Leadore320241975
Bates319941992
Daniels Res320191988
Preston319911988
Springfield219691969
Ririe220191988
Dougal Res220241988
Blackft Res120091985
Twin Buttes120072002
Kyle Canyon120221989
Squirrel120241971
Craters120181982
Triangle120241985
Pocatello120171980
Crane Creek119931993
Picabo120172017
Hot Spring120081995
Sawtooth Cty120022002

Green-tailed Towhee Population Trend in Other States

arizonacaliforniacoloradomontananevadanew-mexicooregontexasutahwyoming

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