BirdAnalyst
Species · BCR 35 · BBS 2025 Release · 1966–2024

Double-crested Cormorant In Chihuahuan Desert

All regionsChihuahuan DesertWetland birds

Double-crested Cormorant in Chihuahuan Desert has surged: up 106% on the route-weighted index since 1996.

+106%Since 1996TrendPercent 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 →
6Routes 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 →
19YearsYears 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 Chihuahuan Desert: up 106% on the route-weighted index since 1996.

Forecast

If the recent trend holds, Double-crested Cormorant in Chihuahuan Desert is projected to fall about 53% by 2026 — from 0.16 in 2021 to a central estimate of 0.07 (95% range 0.00–0.50). A 5-year backtest shows a typical error of ±97%, with 100% of held-out values landing inside the 95% band.

-53%Change by 2026TrendPercent 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 2026 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.5095% 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 →
±97%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 Chihuahuan Desert is projected to fall about 53% by 2026 — from 0.16 in 2021 to a central estimate of 0.07 (95% range 0.00–0.50). A 5-year backtest shows a typical error of ±97%, with 100% of held-out values landing inside the 95% band.19882026
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 →
20220.090.000.51
20230.080.000.51
20240.080.000.50
20250.080.000.50
20260.070.000.50

Routes In Chihuahuan Desert

Routes recording Double-crested Cormorant in Chihuahuan Desert.
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 →
LaborcitaNEW-MEXICO32011
PresidioTEXAS32021
Quitman Canyon 2TEXAS22021
JornadaNEW-MEXICO11996
MesillaNEW-MEXICO11999
Quitman Cyn.TEXAS12007

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