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

Ruddy Duck Population Trend in Colorado

All statesWaterfowl

Ruddy Duck in Colorado has surged: up 120% on the route-weighted index since 1977.

+120%Since 1977TrendPercent 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 →
29Routes 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 →
43YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Ruddy Duck 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 increasecomputed 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 →

Ruddy Duck has surged in Colorado: up 120% on the route-weighted index since 1977.

Ruddy Duck Population Forecast in Colorado

If the recent trend holds, Ruddy Duck in Colorado is projected to stay roughly flat through 2029, near 0.41 (95% range 0.07–0.75). A 5-year backtest shows a typical error of ±60.4%, with 100% of held-out values landing inside the 95% band.

-9%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 →
0.41Projected 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 →
0.07–0.7595% 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 →
±60.4%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, Ruddy Duck in Colorado is projected to stay roughly flat through 2029, near 0.41 (95% range 0.07–0.75). A 5-year backtest shows a typical error of ±60.4%, with 100% of held-out values landing inside the 95% band.19742029
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 →
20250.390.040.73
20260.390.050.73
20270.400.060.74
20280.410.060.75
20290.410.070.75

Ruddy Duck Survey Routes in Colorado

Routes recording Ruddy Duck 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 →
Kiowa4320152015
Guffey2520152015
Wildhorse L2420152015
Rio Grnds Rs1520241991
Mcphee Res.1520241997
Dinosaur820241995
Nunn820172015
Pritchett620082008
Piedra620231992
Dolores519841974
Cortez 2520152013
Last Chance419871987
Julesburg420212002
Baxter Pass419971997
Alamosa420241988
Lamar320212021
Fleming219771977
Falfa220141980
Walden220211990
Amherst220112011
Tincup220072007
Neegrande219971996
Cochetopa Pass220242017
San Luis219931991
Tarryall120182018

Ruddy Duck Population Trend in Other States

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