BirdAnalyst
Species · BCR 36 · BBS 2026 Release · 1966–2025

Neotropic Cormorant In Tamaulipan Brushlands

All regionsTamaulipan BrushlandsWetland birds

Neotropic Cormorant in Tamaulipan Brushlands has fallen sharply: down 52% on the route-weighted index since 1978.

-52%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 →
14Routes 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 →
24YearsYears 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 →

Neotropic Cormorant has fallen sharply in Tamaulipan Brushlands: down 52% on the route-weighted index since 1978.

Neotropic Cormorant In Tamaulipan Brushlands Population Forecast

If the recent trend holds, Neotropic Cormorant in Tamaulipan Brushlands is projected to rise about 124% by 2030 — from 0.27 in 2025 to a central estimate of 0.61 (95% range 0.00–2.0). A 5-year backtest shows a typical error of ±199.5%, with 100% of held-out values landing inside the 95% band.

+124%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 →
0.61Projected 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 →
0.00–2.095% 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 →
±199.5%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, Neotropic Cormorant in Tamaulipan Brushlands is projected to rise about 124% by 2030 — from 0.27 in 2025 to a central estimate of 0.61 (95% range 0.00–2.0). A 5-year backtest shows a typical error of ±199.5%, with 100% of held-out values landing inside the 95% band.19722030
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 →
20260.620.002.1
20270.620.002.1
20280.620.002.0
20290.610.002.0
20300.610.002.0

Routes In Tamaulipan Brushlands

Routes recording Neotropic Cormorant in Tamaulipan Brushlands.
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 →
KingsvilleTEXAS432007
ProgresoTEXAS302009
RachalTEXAS162011
San YgnacioTEXAS151982
George WestTEXAS82015
Encinal 2TEXAS62022
HeidelbergTEXAS42023
RaymondvilleTEXAS32025
EncinalTEXAS22006
Agua NuevaTEXAS12018
ZapataTEXAS11982
Catarina 2TEXAS12011
MillettTEXAS12004
Cavasara Cr.TEXAS12009

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