BirdAnalyst
Species · Colorado · BBS 2025 Release · 1966–2024

Ferruginous Hawk Population Trend in Colorado

All statesGeneralists

Ferruginous Hawk in Colorado has fallen sharply: down 58% on the route-weighted index since 1970.

-58%Since 1970
67Routes In State
56Years

Notable Ferruginous Hawk Trends in Colorado

long arc declinecomputed index

Ferruginous Hawk has fallen sharply in Colorado: down 58% on the route-weighted index since 1970.

Ferruginous Hawk Population Forecast in Colorado

If the recent trend holds, Ferruginous Hawk in Colorado is projected to rise about 99% by 2029 — from 0.11 in 2024 to a central estimate of 0.23 (95% range 0.00–0.53). A 5-year backtest shows a typical error of ±89.8%, with 100% of held-out values landing inside the 95% band.

+99%Change by 2029
0.23Projected 2029 index
0.00–0.5395% range
±89.8%Backtest error
19682029
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
20250.230.000.54
20260.230.000.54
20270.230.000.53
20280.230.000.53
20290.230.000.53

Ferruginous Hawk Survey Routes in Colorado

Routes recording Ferruginous Hawk in Colorado.
Hudson819991993
Pinneo420191981
Blanca319861981
Mica Butte319811968
Gordon Creek320051997
Crowley320241989
Nunn320181995
Como320232023
Stoneham320211994
Prospect Val319931993
Last Chance 2320222022
Maybell220181996
Arsenal220131992
Lamar220171975
Gilpin220241972
Doyle Bridge 2220232006
Cheyenne220221990
Antonito220012001
Pritchett220171995
Mosca220242009
Great Divide120222016
Yampa120102010
Briggsdale120231969
Fleming120151999
Rockport120231994

Ferruginous Hawk Population Trend in Other States

arizonacaliforniaidahokansasmontananebraskanevadanew-mexiconorth-dakotaoklahomaoregonsouth-dakotatexasutahwashingtonwyoming

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