Species · Louisiana · BBS 2025 Release · 1966–2024

Double-crested Cormorant Population Trend in Louisiana

Double-crested Cormorant in Louisiana has declined: down 32% on the route-weighted index since 1975.

-32%Since 1975
27Routes In State
43Years

Notable Double-crested Cormorant Trends in Louisiana

No notable trend signals for Double-crested Cormorant in Louisiana. See the full index history below.

Double-crested Cormorant Population Forecast in Louisiana

If the recent trend holds, Double-crested Cormorant in Louisiana is projected to rise about 468% by 2029 — from 0.07 in 2024 to a central estimate of 0.41 (95% range 0.00–1.4). A 5-year backtest shows a typical error of ±886.5%, with 100% of held-out values landing inside the 95% band.

+468%Change by 2029
0.41Projected 2029 index
0.001.495% range
±886.5%Backtest error
19672029
Projection of the recent trend (dashed) with 80/95% bands — a projection, not a prediction. Habitat, climate, and land use are not modeled.
YearProjected index95% low95% high
20250.420.001.4
20260.420.001.4
20270.420.001.4
20280.420.001.4
20290.410.001.4

Double-crested Cormorant Survey Routes in Louisiana

Routes recording Double-crested Cormorant in Louisiana.
Creole2019871975
Gran Chenier1419821967
Esther920141988
Atchafalaya419961996
Zwolle420231998
Sabine Nwr 2320172009
Morgan City220222022
Belair220071995
Sabine Nwr220031992
Haughton120011998
Junior119911988
River Road120241995
Tensas Nwr120042004
Bickham119851985
Baton Rouge120211996
Hackberry119711971
Shaw120091990
Longstreet119901990
Forked Island 2120102010
Glencoe119981998
Ramah120121993
Kaplan120192001
Woodlawn120182016
Port Allen120112003
Frogmore120242024

Double-crested Cormorant Population Trend in Other States

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