BirdAnalyst
Species · BBS 2025 Release · 1966–2024

Peregrine Falcon

FalconidaeBirds of preyFalco peregrinus

Peregrine Falcon has surged: up 413% on the route-weighted index since 1972.

+413%Since 1972TrendPercent 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 →
288RoutesSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
47Years 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 Peregrine Falcon

The Peregrine Falcon (Falco peregrinus) is a North American member of the Falcons & Caracaras (Falconidae). In this analysis it is grouped with the birds of prey.

Size
10–23.5 in long (25–60 cm) — a streamlined 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 288 Breeding Bird Survey routes across 31 states, most concentrated in the Southern Rockies / Colorado Plateau.
Family
Falconidae · Birds of prey

Notable Peregrine Falcon 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 Peregrine Falcon. See the full index history below.

Peregrine Falcon Population Forecast

If the recent trend holds, Peregrine Falcon is projected to stay roughly flat through 2029, near 0.01 (95% range 0.01–0.01). A 5-year backtest shows a typical error of ±9.9%, 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 →
0.01Projected 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 →
0.01–0.0195% 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 →
±9.9%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, Peregrine Falcon is projected to stay roughly flat through 2029, near 0.01 (95% range 0.01–0.01). A 5-year backtest shows a typical error of ±9.9%, with 100% of held-out values landing inside the 95% band.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 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 →
20250.010.010.01
20260.010.010.01
20270.010.010.01
20280.010.010.01
20290.010.010.01

Where the Peregrine Falcon Is Detected

BBS routes recording Peregrine Falcon, sized by most recent count.

Peregrine Falcon Population Trend by State

Peregrine Falcon 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 →
Alabamainsufficient datan/a2
Alaska+48%199823
Arizona-64%197826
California+17%197541
Colorado+257%199935
Connecticutinsufficient datan/a1
Delawareinsufficient datan/a1
Idahoinsufficient datan/a9
Indianainsufficient datan/a1
Maineinsufficient datan/a2
Marylandinsufficient datan/a1
Michiganinsufficient datan/a4
Minnesotainsufficient datan/a4
Montana+7%199311
Nebraskainsufficient datan/a1
Nevadainsufficient datan/a3
New Hampshireinsufficient datan/a5
New Jerseyinsufficient datan/a2
New Mexico+19%200211
New Yorkinsufficient datan/a3
Oklahomainsufficient datan/a1
Oregon+166%200114
Pennsylvaniainsufficient datan/a3
Tennesseeinsufficient datan/a1
Texasinsufficient datan/a7
Utah-51%199131
Vermontinsufficient datan/a6
Virginiainsufficient datan/a2
Washington+196%199617
Wisconsininsufficient datan/a3
Wyoming+19%199617

Peregrine Falcon Population Trend by Region

Bird Conservation Regions are the ecological unit for trends.

Peregrine Falcon 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 4+263%199816
Northern Pacific Rainforest-6%197729
Great Basin+501%199534
Northern Rockies+63%199130
Southern Rockies / Colorado Plateau+3%199167
Prairie Hardwood Transition+3%20024
Coastal California+136%197918
Sierra Madre Occidental-73%197814

Peregrine Falcon Conservation Status

Our route-weighted index shows it up about 413% since 1972.

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