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

Chukar Population Trend in Colorado

All statesGeneralists

Chukar in Colorado has fallen sharply: down 66% on the route-weighted index since 1985.

-66%Since 1985TrendPercent 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 →
6Routes 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 →
29YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Chukar 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 declinecomputed 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 →

Chukar has fallen sharply in Colorado: down 66% on the route-weighted index since 1985.

Chukar Population Forecast in Colorado

If the recent trend holds, Chukar in Colorado is projected to fall about 78% by 2029 — from 0.10 in 2024 to a central estimate of 0.02 (95% range 0.00–0.14). A 5-year backtest shows a typical error of ±121.6%, with 80% of held-out values landing inside the 95% band.

-78%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 →
0.02Projected 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 →
0.00–0.1495% 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 →
±121.6%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, Chukar in Colorado is projected to fall about 78% by 2029 — from 0.10 in 2024 to a central estimate of 0.02 (95% range 0.00–0.14). A 5-year backtest shows a typical error of ±121.6%, with 80% of held-out values landing inside the 95% band.19752029
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 →
20250.030.000.15
20260.030.000.14
20270.030.000.14
20280.020.000.14
20290.020.000.14

Chukar Survey Routes in Colorado

Routes recording Chukar 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 →
Baxter Pass720241995
Douglas Pass320241982
Mesaverde Np220062006
Delta120011975
Basin120092009
Wray Gulch119881988

Chukar Population Trend in Other States

arizonacaliforniaidahomontananevadaoregontexasutahwashingtonwyoming

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