Species · Colorado · BBS 2025 Release · 1966–2024

Long-billed Curlew Population Trend in Colorado

Long-billed Curlew in Colorado has collapsed: down 92% on the route-weighted index since 1973.

-92%Since 1973
33Routes In State
51Years

Notable Long-billed Curlew Trends in Colorado

long arc declinecomputed index

Long-billed Curlew has collapsed in Colorado: down 92% on the route-weighted index since 1973.

Long-billed Curlew Population Forecast in Colorado

If the recent trend holds, Long-billed Curlew in Colorado is projected to fall about 100% by 2029 — from 0.19 in 2024 to a central estimate of 0.00 (95% range 0.00–1.5). A 5-year backtest shows a typical error of ±177.4%, with 100% of held-out values landing inside the 95% band.

-100%Change by 2029
0.00Projected 2029 index
0.001.595% range
±177.4%Backtest error
19692029
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
20250.000.001.5
20260.000.001.5
20270.000.001.5
20280.000.001.5
20290.000.001.5

Long-billed Curlew Survey Routes in Colorado

Routes recording Long-billed Curlew in Colorado.
Last Chance1119811981
Sheridan Lak1119981998
Villegreen820241996
Haswell519991992
Edler520241992
Wildhorse L419991999
Campo420191988
Pinneo319941973
Two Buttes319941973
Bethune320112011
Ninaview320241995
Fleming219771977
Rush219841984
Fruita219891989
Edison220101993
Karval219961996
Pritchett220241995
Mosca220061993
Gardner220032003
Maybell119701970
Abarr120151969
Boyero119971997
Lamar120211973
Gilpin120021970
Wilson Creek120112011

Long-billed Curlew Population Trend in Other States

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