BirdAnalyst
Species · BBS 2025 Release · 1966–2024

Rough-legged Hawk

AccipitridaeBirds of preyButeo lagopus

Rough-legged Hawk has no long-term trend on record.

n/aSince n/aTrendPercent 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 →
26RoutesSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
35Years SurveyedYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

About the Rough-legged Hawk

The Rough-legged Hawk (Buteo lagopus) 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 26 Breeding Bird Survey routes across 1 state, most concentrated in the BCR 4.
Family
Accipitridae · Birds of prey

Notable Rough-legged Hawk TrendsNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

No notable trend signals for Rough-legged Hawk. See the full index history below.

Rough-legged Hawk Population Forecast

If the recent trend holds, Rough-legged Hawk is projected to stay roughly flat through 2029, near 0.00 (95% range 0.00–0.00). A 5-year backtest shows a typical error of ±84.9%, with 100% of held-out values landing inside the 95% band.

n/aChange by 2029TrendPercent 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 →
0.00Projected 2029 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.0095% 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 →
±84.9%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, Rough-legged Hawk is projected to stay roughly flat through 2029, near 0.00 (95% range 0.00–0.00). A 5-year backtest shows a typical error of ±84.9%, with 100% of held-out values landing inside the 95% band.19872029
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 →
20250.000.000.00
20260.000.000.00
20270.000.000.00
20280.000.000.00
20290.000.000.00

Where the Rough-legged Hawk Is Detected

BBS routes recording Rough-legged Hawk, sized by most recent count.

Rough-legged Hawk Population Trend by State

Rough-legged Hawk population trend by state.
TrendPercent 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 →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
Alaska+121%199126

Rough-legged Hawk Population Trend by Region

Bird Conservation Regions are the ecological unit for trends.

Rough-legged Hawk population trend by Bird Conservation Region.
TrendPercent 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 →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
BCR 2-26%19939
BCR 3+67%19953
BCR 4-4%199314

Rough-legged Hawk Conservation Status

Rough-legged Hawk is tracked across BBS survey routes; no formal conservation-status flag is recorded here.

Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22. Trend is a route-weighted relative-abundance index, not an absolute population.