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

Northern Bobwhite Population Trend in Colorado

All statesGame birds

Northern Bobwhite in Colorado has declined: down 50% on the route-weighted index since 1970.

-50%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 →
27Routes 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 →
56YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Northern Bobwhite 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 →

No notable trend signals for Northern Bobwhite in Colorado. See the full index history below.

Northern Bobwhite Population Forecast in Colorado

If the recent trend holds, Northern Bobwhite in Colorado is projected to fall about 100% by 2030 — from 0.40 in 2025 to a central estimate of 0.00 (95% range 0.00–0.80). A 5-year backtest shows a typical error of ±65.1%, with 100% of held-out values landing inside the 95% band.

-100%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 →
0.00Projected 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 →
0.00–0.8095% 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 →
±65.1%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, Northern Bobwhite in Colorado is projected to fall about 100% by 2030 — from 0.40 in 2025 to a central estimate of 0.00 (95% range 0.00–0.80). A 5-year backtest shows a typical error of ±65.1%, 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 →
20260.030.000.82
20270.020.000.81
20280.010.000.80
20290.000.000.80
20300.000.000.80

Northern Bobwhite Survey Routes in Colorado

Routes recording Northern Bobwhite 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 →
Fort Morgan1220251996
Doyle Bridge1219971992
Edler1220251993
Campo1120252016
Neegrande420252023
Arsenal319911991
Rush320042004
Pritchett320251999
Last Chance219741974
Boyero219931990
Doyle Bridge 2220161998
Waverly220191989
Nunn220172017
Julesburg220172004
Stoneham220192001
Pinneo120121976
Fleming120121973
Abarr120191968
Lamar120241973
Two Buttes120251973
Hudson120171989
Gordon Creek120192019
Crowley120171990
Cheyenne120082008
Burlington120242018

Northern Bobwhite Population Trend in Other States

alabamaarkansasconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourinebraskanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasvermontvirginiawashingtonwest-virginiawisconsinwyoming

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