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

Double-crested Cormorant Population Trend in Wyoming

All statesWetland birds

Double-crested Cormorant in Wyoming has edged up: up 14% on the route-weighted index since 1978.

+14%Since 1978TrendPercent 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 →
38Routes 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 →
48YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Double-crested Cormorant Trends in WyomingNotable 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 Double-crested Cormorant in Wyoming. See the full index history below.

Double-crested Cormorant Population Forecast in Wyoming

If the recent trend holds, Double-crested Cormorant in Wyoming is projected to rise about 34% by 2029 — from 0.19 in 2024 to a central estimate of 0.26 (95% range 0.00–0.73). A 5-year backtest shows a typical error of ±143.1%, with 100% of held-out values landing inside the 95% band.

+34%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 →
0.26Projected 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 →
0.00–0.7395% 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 →
±143.1%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, Double-crested Cormorant in Wyoming is projected to rise about 34% by 2029 — from 0.19 in 2024 to a central estimate of 0.26 (95% range 0.00–0.73). A 5-year backtest shows a typical error of ±143.1%, with 100% of held-out values landing inside the 95% band.19762029
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 →
20250.260.000.74
20260.260.000.74
20270.260.000.74
20280.260.000.73
20290.260.000.73

Double-crested Cormorant Survey Routes in Wyoming

Routes recording Double-crested Cormorant in Wyoming.
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 →
Soda Well1719811981
Fontenelle1020241982
Rock River719991992
Sybille Cyn620132013
Harmony620141982
Moose520141992
Elk Horn420002000
Colter Bay319961996
Kaycee320242024
Cody219971993
Otto220152015
Brookhurst220221976
Dayton220242012
Ethete220211991
Sussex220102010
Sweetwater219971997
Bucknum219971996
Yellowstone120221993
Dubois120102010
Midvale120241988
Natrona119901988
Seely 2120042004
Buford119981998
Yoder120121987
Mammoth120122012

Double-crested Cormorant Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsin

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