BirdAnalyst
Species · BCR 11 · BBS 2026 Release · 1966–2025

Double-crested Cormorant In Prairie Potholes

All regionsPrairie PotholesWetland birds

Double-crested Cormorant in Prairie Potholes has surged: up 234% on the route-weighted index since 1969.

+234%Since 1969TrendPercent 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 →
87Routes In RegionSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
58YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable SignalsNotable 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 →

Double-crested Cormorant has surged in Prairie Potholes: up 234% on the route-weighted index since 1969.

Double-crested Cormorant In Prairie Potholes Population Forecast

If the recent trend holds, Double-crested Cormorant in Prairie Potholes is projected to rise about 65% by 2030 — from 3.3 in 2025 to a central estimate of 5.5 (95% range 1.8–9.1). A 5-year backtest shows a typical error of ±144.1%, with 80% of held-out values landing inside the 95% band.

+65%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 →
5.5Projected 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 →
1.8–9.195% 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 →
±144.1%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 Prairie Potholes is projected to rise about 65% by 2030 — from 3.3 in 2025 to a central estimate of 5.5 (95% range 1.8–9.1). A 5-year backtest shows a typical error of ±144.1%, with 80% of held-out values landing inside the 95% band.19672030
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 →
20265.11.58.8
20275.21.68.9
20285.31.79.0
20295.41.79.0
20305.51.89.1

Routes In Prairie Potholes

Routes recording Double-crested Cormorant in Prairie Potholes.
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 →
DanzigNORTH-DAKOTA432014
StanleyNORTH-DAKOTA432024
Big StoneMINNESOTA412012
BuchananNORTH-DAKOTA392025
EdgeleyNORTH-DAKOTA372025
Lakota 2NORTH-DAKOTA322025
WebsterNORTH-DAKOTA242024
Danzig 2NORTH-DAKOTA222025
Horsehead LkNORTH-DAKOTA212025
ChinookMONTANA182017
ChokioMINNESOTA162025
AbercrombieNORTH-DAKOTA132005
RaymondSOUTH-DAKOTA132021
WylieMINNESOTA121998
RoswellSOUTH-DAKOTA112014
Great FallsMONTANA92016
WalcottNORTH-DAKOTA92017
TracyMINNESOTA82025
EmeradoNORTH-DAKOTA82024
TurtonSOUTH-DAKOTA82008
MontpelierNORTH-DAKOTA72025
GlyndonMINNESOTA62025
WorthingtonMINNESOTA62025
CarpioNORTH-DAKOTA62023
Wild RoseNORTH-DAKOTA62025

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