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Species · Wyoming · BBS 2026 Release · 1966–2025

Swainson's Hawk Population Trend in Wyoming

All statesBirds of prey

Swainson's Hawk in Wyoming has surged: up 137% on the route-weighted index since 1970.

+137%Since 1970TrendPercent 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 →
100Routes In StateSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
56YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Swainson's Hawk Trends in WyomingNotable 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 Wyoming: up 137% on the route-weighted index since 1970.

Swainson's Hawk Population Forecast in Wyoming

If the recent trend holds, Swainson's Hawk in Wyoming is projected to rise about 44% by 2030 — from 0.37 in 2025 to a central estimate of 0.53 (95% range 0.29–0.77). A 5-year backtest shows a typical error of ±23.1%, with 100% of held-out values landing inside the 95% band.

+44%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 →
0.53Projected 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 →
0.29–0.7795% 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 →
±23.1%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 Wyoming is projected to rise about 44% by 2030 — from 0.37 in 2025 to a central estimate of 0.53 (95% range 0.29–0.77). A 5-year backtest shows a typical error of ±23.1%, 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 →
20260.520.280.76
20270.520.280.76
20280.530.290.77
20290.530.290.77
20300.530.290.77

Swainson's Hawk Survey Routes in Wyoming

Routes recording Swainson's Hawk in Wyoming.
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 →
Harmony820231982
Elk Horn520181991
Clarkelen419781968
Buford420251977
Wamsutter420251990
Seedskadee420161986
Fontenelle320251984
Ethete320231992
Highlight320071989
Boulder320251984
Mtn View319801980
Walcott320251982
Chugwater320241982
Midvale220251998
Cumberland219801980
Yoder220251986
Mammoth219911985
Dayton220182008
Soda Well220231999
Harland Flat220251990
Riverview220161982
Gas Hills220121992
Pathfinder220241984
Leo220252012
Rock River220161990

Swainson's Hawk Population Trend in Other States

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