Ferruginous Hawk
Ferruginous Hawk has surged: up 491% on the route-weighted index since 1969.
About the Ferruginous Hawk
The Ferruginous Hawk (Buteo regalis) is a North American member of the Hawks, Eagles & Kites (Accipitridae). In this analysis it is grouped with the birds of prey.
- Size
- 17.5–39.5 in long (45–100 cm) — a medium to large raptor (typical for the family)
- Habitat
- Open country, woodlands, cliffs and wetlands, hunting from the air or a high perch.
- Diet
- Live prey — small mammals, birds, reptiles, fish and large insects (carrion for vultures).
- Range
- Recorded on 515 Breeding Bird Survey routes across 17 states, most concentrated in the Great Basin.
- Family
- Accipitridae · Birds of prey
Notable Ferruginous Hawk Trends
No notable trend signals for Ferruginous Hawk. See the full index history below.
Ferruginous Hawk Population Forecast
If the recent trend holds, Ferruginous Hawk is projected to rise about 21% by 2029 — from 0.07 in 2024 to a central estimate of 0.08 (95% range 0.06–0.11). A 5-year backtest shows a typical error of ±31.7%, with 80% of held-out values landing inside the 95% band.
| Year | Projected index | 95% low | 95% high |
|---|---|---|---|
| 2025 | 0.08 | 0.05 | 0.10 |
| 2026 | 0.08 | 0.05 | 0.10 |
| 2027 | 0.08 | 0.05 | 0.10 |
| 2028 | 0.08 | 0.05 | 0.11 |
| 2029 | 0.08 | 0.06 | 0.11 |
Where the Ferruginous Hawk Is Detected
BBS routes recording Ferruginous Hawk, sized by most recent count.
Ferruginous Hawk Population Trend by State
| Arizona | insufficient data | n/a | 5 |
| California | insufficient data | n/a | 4 |
| Colorado | -58% | 1970 | 67 |
| Idaho | +675% | 1977 | 26 |
| Kansas | +49% | 1974 | 16 |
| Montana | +238% | 1973 | 61 |
| Nebraska | -10% | 1981 | 17 |
| Nevada | +35% | 1970 | 22 |
| New Mexico | -64% | 1979 | 31 |
| North Dakota | +4% | 1969 | 35 |
| Oklahoma | +4% | 1975 | 7 |
| Oregon | +65% | 1973 | 33 |
| South Dakota | +616% | 1973 | 32 |
| Texas | -60% | 1975 | 8 |
| Utah | -60% | 1979 | 44 |
| Washington | -64% | 1982 | 13 |
| Wyoming | -41% | 1970 | 94 |
Ferruginous Hawk Population Trend by Region
Bird Conservation Regions are the ecological unit for trends.
| Great Basin | +315% | 1970 | 118 |
| Northern Rockies | +213% | 1973 | 82 |
| Prairie Potholes | +448% | 1969 | 49 |
| Southern Rockies / Colorado Plateau | +55% | 1974 | 46 |
| Badlands and Prairies | +60% | 1970 | 98 |
| Shortgrass Prairie | +9% | 1970 | 96 |
| Central Mixed Grass Prairie | -9% | 1974 | 20 |
Ferruginous Hawk Conservation Status
Our route-weighted index shows it up about 491% since 1969.
Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22. Trend is a route-weighted relative-abundance index, not an absolute population.