BirdAnalyst
Species · North Dakota · BBS 2025 Release · 1966–2024

Swainson's Hawk Population Trend in North Dakota

All statesGeneralists

Swainson's Hawk in North Dakota has surged: up 114% on the route-weighted index since 1969.

+114%Since 1969TrendPercent 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 →
48Routes 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 →
57YearsYears 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 North DakotaNotable 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 North Dakota: up 114% on the route-weighted index since 1969.

Swainson's Hawk Population Forecast in North Dakota

If the recent trend holds, Swainson's Hawk in North Dakota is projected to rise about 14% by 2029 — from 1.4 in 2024 to a central estimate of 1.6 (95% range 0.84–2.4). A 5-year backtest shows a typical error of ±25.5%, with 100% of held-out values landing inside the 95% band.

+14%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 →
1.6Projected 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 →
0.84–2.495% 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 →
±25.5%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 North Dakota is projected to rise about 14% by 2029 — from 1.4 in 2024 to a central estimate of 1.6 (95% range 0.84–2.4). A 5-year backtest shows a typical error of ±25.5%, with 100% of held-out values landing inside the 95% band.19672029
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 →
20251.60.782.4
20261.60.802.4
20271.60.812.4
20281.60.832.4
20291.60.842.4

Swainson's Hawk Survey Routes in North Dakota

Routes recording Swainson's Hawk in North Dakota.
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 →
Lake George1120221969
Gorham620181968
Wild Rose520241982
Buchanan420241967
Carson420241988
Montpelier420221991
Edgeley320241980
Dickinson320241968
Stanley320241967
Glen Ullin320221986
Douglas Crk320231982
Horsehead Lk220241980
Lakota220041979
Ft Yates220041971
Tobacco220021968
Bowman220241968
Zap220241979
Cedar Creek220221971
Powers Lake220241982
Danzig 2220242019
Forman120241979
Walcott119921981
Sydney119831970
Danzig120141982
Kempton120161969

Swainson's Hawk Population Trend in Other States

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