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

Townsend's Solitaire Population Trend in Colorado

All statesForest birds

Townsend's Solitaire in Colorado has surged: up 93% on the route-weighted index since 1970.

+93%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 →
81Routes 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 Townsend's Solitaire Trends in ColoradoNotable 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 →

Townsend's Solitaire has surged in Colorado: up 93% on the route-weighted index since 1970.

Townsend's Solitaire Population Forecast in Colorado

If the recent trend holds, Townsend's Solitaire in Colorado is projected to rise about 59% by 2029 — from 0.39 in 2024 to a central estimate of 0.62 (95% range 0.33–0.91). A 5-year backtest shows a typical error of ±70.4%, with 60% of held-out values landing inside the 95% band.

+59%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 →
0.62Projected 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 →
0.33–0.9195% 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 →
±70.4%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, Townsend's Solitaire in Colorado is projected to rise about 59% by 2029 — from 0.39 in 2024 to a central estimate of 0.62 (95% range 0.33–0.91). A 5-year backtest shows a typical error of ±70.4%, with 60% 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 →
20250.590.300.88
20260.600.310.89
20270.610.320.90
20280.610.320.91
20290.620.330.91

Townsend's Solitaire Survey Routes in Colorado

Routes recording Townsend's Solitaire in Colorado.
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 →
Piceance Basin1120042003
Deadman Rd.820241994
Moon Pass820242003
Buffalo Park720231992
Mount Evans620241996
Castleton320221988
Villegreen319981998
Guanella Pas320241992
Dinosaur320021999
Weston Pass319991999
Como320241996
Cochetopa Pass320232001
Yampa220191971
Wilson Creek220172005
Lost Lake220241993
Tarryall220191995
Lake City220011997
Pinos Creek219891989
Colona 2220192017
Steamboat L.220181999
Baxter Pass220162013
Powderhorn220232002
Stillwater Pass220091999
Gold Hill220121998
Owl Creek Pass220131998

Townsend's Solitaire Population Trend in Other States

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