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

American Robin Population Trend in Colorado

All statesForest birds

American Robin in Colorado has edged up: up 20% on the route-weighted index since 1970.

+20%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 →
155Routes 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 American Robin 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 American Robin in Colorado. See the full index history below.

American Robin Population Forecast in Colorado

If the recent trend holds, American Robin in Colorado is projected to rise about 16% by 2029 — from 23 in 2024 to a central estimate of 27 (95% range 20–34). A 5-year backtest shows a typical error of ±5.8%, with 100% of held-out values landing inside the 95% band.

+16%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 →
27Projected 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 →
20–3495% 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 →
±5.8%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, American Robin in Colorado is projected to rise about 16% by 2029 — from 23 in 2024 to a central estimate of 27 (95% range 20–34). A 5-year backtest shows a typical error of ±5.8%, 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 →
2025272033
2026272033
2027272033
2028272034
2029272034

American Robin Survey Routes in Colorado

Routes recording American Robin 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 →
Yampa19320231969
Buffalo Park19120231992
Deadman Rd.13120241992
Dolores Riv11420241988
Stillwater Pass10720091998
Ragged Mtn.10320191994
Fox Creek6520241993
Aspen6420241979
Douglas Pass6220241982
Castleton6220241988
Gribbles Prk6120241994
Mcphee Res.5820241996
Blackhead Pk5720211991
Elbert5720241998
Marshall Pas5620191995
Stillwater Pass 25420242010
Groundhog Rs5220241992
Steamboat L.5220241996
Ludlow5220161998
Lizard Head Pass5120242001
Pagosa Spgs4919821968
Red Cliff4920241989
South Fork4820241994
Cheesman Lk4620241969
Colona4520141972

American Robin Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniaconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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