BirdAnalyst
Species · BCR 34 · BBS 2025 Release · 1966–2024

Swainson's Hawk In Sierra Madre Occidental

All regionsSierra Madre OccidentalGeneralists

Swainson's Hawk in Sierra Madre Occidental has surged: up 527% on the route-weighted index since 1971.

+527%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 →
19Routes 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 →
50YearsYears 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 527% 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 fall about 50% by 2029 — from 1.6 in 2024 to a central estimate of 0.81 (95% range 0.00–3.2). A 5-year backtest shows a typical error of ±38.1%, with 100% of held-out values landing inside the 95% band.

-50%Change 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 →
0.81Projected 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 →
0.00–3.295% 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 →
±38.1%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 fall about 50% by 2029 — from 1.6 in 2024 to a central estimate of 0.81 (95% range 0.00–3.2). A 5-year backtest shows a typical error of ±38.1%, with 100% of held-out values landing inside the 95% band.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 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 →
20250.800.003.2
20260.800.003.2
20270.810.003.2
20280.810.003.2
20290.810.003.2

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 →
Sunizona 2ARIZONA92024
San SimonARIZONA72024
PatagoniaARIZONA42024
McnealARIZONA42024
Peña BlancaARIZONA22024
SunizonaARIZONA21997
PomereneARIZONA12024
MaineARIZONA11997
Skull ValleyARIZONA12024
CutterARIZONA11995
AlpineARIZONA12021
AmadoARIZONA12022
SahuaritaARIZONA12009
Clay SpringARIZONA12022
PortalARIZONA12005
DragoonARIZONA12000
RuckerARIZONA12004
Vicks PeakNEW-MEXICO12016
MagdalenaNEW-MEXICO12024

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