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

Steller's Jay Population Trend in Colorado

All statesGeneralists

Steller's Jay in Colorado has declined: down 26% on the route-weighted index since 1970.

-26%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 →
86Routes 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 Steller's Jay 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 Steller's Jay in Colorado. See the full index history below.

Steller's Jay Population Forecast in Colorado

If the recent trend holds, Steller's Jay in Colorado is projected to stay roughly flat through 2029, near 1.5 (95% range 0.47–2.6). A 5-year backtest shows a typical error of ±11.7%, with 100% of held-out values landing inside the 95% band.

-7%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 →
1.5Projected 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 →
0.47–2.695% 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 →
±11.7%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, Steller's Jay in Colorado is projected to stay roughly flat through 2029, near 1.5 (95% range 0.47–2.6). A 5-year backtest shows a typical error of ±11.7%, 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 →
20251.50.442.6
20261.50.452.6
20271.50.452.6
20281.50.462.6
20291.50.472.6

Steller's Jay Survey Routes in Colorado

Routes recording Steller's Jay 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 →
Cortez 21920092009
Fox Creek1620241993
Mount Evans1520241997
Deadman Rd.1420241992
Blackhead Pk1120211991
Comanche Pk1120241995
Yampa1020231990
Pagosa Spgs919821968
Como920241996
Guffey820241990
Gold Hill820121998
Wet Mtns.720231993
Stillwater Pass620091998
Rollins Pass620211998
Owl Creek Pass620241998
Maybell519701970
Parlin520221968
Tarryall520231988
Buffalo Park520231995
Thomasville520181992
Elbert520241998
Haycamp Mesa520241998
Lizard Head Pass520242001
Moon Pass520241998
Lost Lake420241995

Steller's Jay Population Trend in Other States

alaskaarizonacaliforniaidahomontananevadanew-mexicooregontexasutahwashingtonwyoming

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