BirdAnalyst
Species · BCR 34 · BBS 2026 Release · 1966–2025

Swainson's Hawk In Sierra Madre Occidental

All regionsSierra Madre OccidentalBirds of prey

Swainson's Hawk in Sierra Madre Occidental has surged: up 439% on the route-weighted index since 1971.

+439%Since 1971TrendPercent 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 →
20Routes In RegionSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
51YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

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

long arc increasecomputed indexTrend sourceWhether the figure is our own computed route-weighted index or an official USGS modeled estimate. The current build labels every trend as computed.Full methodology →

Swainson's Hawk has surged in Sierra Madre Occidental: up 438% on the route-weighted index since 1971.

Swainson's Hawk In Sierra Madre Occidental Population Forecast

If the recent trend holds, Swainson's Hawk in Sierra Madre Occidental is projected to stay roughly flat through 2030, near 0.82 (95% range 0.00–3.2). A 5-year backtest shows a typical error of ±36.8%, with 100% of held-out values landing inside the 95% band.

-8%Change by 2030TrendPercent 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 →
0.82Projected 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–3.295% 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 →
±36.8%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, Swainson's Hawk in Sierra Madre Occidental is projected to stay roughly flat through 2030, near 0.82 (95% range 0.00–3.2). A 5-year backtest shows a typical error of ±36.8%, with 100% of held-out values landing inside the 95% band.19682030
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 →
20260.810.003.1
20270.810.003.1
20280.810.003.1
20290.820.003.1
20300.820.003.2

Routes In Sierra Madre Occidental

Routes recording Swainson's Hawk in Sierra Madre Occidental.
Recent countThe raw number of individuals recorded on this route in its most recent survey year. A single-route tally, not a trend.Full methodology →
San SimonARIZONA72024
PomereneARIZONA62025
AmadoARIZONA62025
Sunizona 2ARIZONA62025
PatagoniaARIZONA42024
McnealARIZONA32025
Peña BlancaARIZONA22024
SunizonaARIZONA21997
Skull Valley 2ARIZONA22025
MaineARIZONA11997
Skull ValleyARIZONA12024
CutterARIZONA11995
AlpineARIZONA12021
SahuaritaARIZONA12009
Clay SpringARIZONA12022
PortalARIZONA12005
DragoonARIZONA12000
RuckerARIZONA12004
Vicks PeakNEW-MEXICO12025
MagdalenaNEW-MEXICO12024

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.