BirdAnalyst
Species · BCR 21 · BBS 2025 Release · 1966–2024

Double-crested Cormorant In Oaks and Prairies

All regionsOaks and PrairiesWetland birds

Double-crested Cormorant in Oaks and Prairies has fallen sharply: down 52% on the route-weighted index since 1982.

-52%Since 1982TrendPercent 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 →
22Routes 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 →
31YearsYears 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 declinecomputed 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 fallen sharply in Oaks and Prairies: down 52% on the route-weighted index since 1982.

Double-crested Cormorant In Oaks and Prairies Population Forecast

If the recent trend holds, Double-crested Cormorant in Oaks and Prairies is projected to fall about 36% by 2029 — from 0.11 in 2024 to a central estimate of 0.07 (95% range 0.00–0.30). A 5-year backtest shows a typical error of ±98.7%, with 100% of held-out values landing inside the 95% band.

-36%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 →
0.07Projected 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 →
0.00–0.3095% 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 →
±98.7%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 Oaks and Prairies is projected to fall about 36% by 2029 — from 0.11 in 2024 to a central estimate of 0.07 (95% range 0.00–0.30). A 5-year backtest shows a typical error of ±98.7%, 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 →
20250.070.000.30
20260.070.000.30
20270.070.000.30
20280.070.000.30
20290.070.000.30

Routes In Oaks and Prairies

Routes recording Double-crested Cormorant in Oaks and Prairies.
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 →
YoakumTEXAS42004
CayugaTEXAS32024
CampbelltonTEXAS22004
Massey LakeTEXAS22023
KosseTEXAS22016
FanninTEXAS22001
CreedmoreTEXAS22000
SchroederTEXAS11982
MuldoonTEXAS12003
Lone OakTEXAS12002
WeatherfordTEXAS12016
AlbanyTEXAS12022
Miller GroveTEXAS12010
SadlerTEXAS12014
HenriettaTEXAS12016
Thornton 2TEXAS12001
CarlosTEXAS12024
Blue RidgeTEXAS12000
Three RiversTEXAS12024
BonnerTEXAS12010
BrucevilleTEXAS12001
ComancheTEXAS12003

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