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

Arid-land Birds In Colorado

All statesColorado

7 species in this guild. As a group they are -20%Guild trendA mean-index aggregate across the species in this group — the structural direction of the guild, with individual-species noise smoothed out.Full methodology → since 1970.

Guild SignalsNotable 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 arid-land birds in Colorado. See the full index history below.

Arid-land Birds In Colorado Population Forecast

If the recent trend holds, Arid-land birds in Colorado is projected to fall about 24% by 2030 — from 1.5 in 2025 to a central estimate of 1.1 (95% range 0.00–3.5). A 5-year backtest shows a typical error of ±31.5%, with 100% of held-out values landing inside the 95% band.

-24%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 →
1.1Projected 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 →
0.00–3.595% 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 →
±31.5%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, Arid-land birds in Colorado is projected to fall about 24% by 2030 — from 1.5 in 2025 to a central estimate of 1.1 (95% range 0.00–3.5). A 5-year backtest shows a typical error of ±31.5%, 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 →
20261.30.003.6
20271.20.003.6
20281.20.003.5
20291.20.003.5
20301.10.003.5

Member Species In Colorado

Arid-land birds species in Colorado.
TrendPercent 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 →
Greater RoadrunnerCuculidae-70%
Canyon TowheePasserellidae-51%
Black-throated SparrowPasserellidae-0%
Sagebrush SparrowPasserellidae+26%
Curve-billed ThrasherMimidae+29%
Brewer's SparrowPasserellidae+93%
Sage ThrasherMimidae+735%

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