BirdAnalyst
Species · Oregon · BBS 2025 Release · 1966–2024

Northern Harrier Population Trend in Oregon

All statesGeneralists

Northern Harrier in Oregon has surged: up 189% on the route-weighted index since 1970.

+189%Since 1970
66Routes In State
56Years

Notable Northern Harrier Trends in Oregon

long arc increasecomputed index

Northern Harrier has surged in Oregon: up 189% on the route-weighted index since 1970.

Northern Harrier Population Forecast in Oregon

If the recent trend holds, Northern Harrier in Oregon is projected to fall about 25% by 2029 — from 0.72 in 2024 to a central estimate of 0.54 (95% range 0.20–0.88). A 5-year backtest shows a typical error of ±61.9%, with 100% of held-out values landing inside the 95% band.

-25%Change by 2029
0.54Projected 2029 index
0.20–0.8895% range
±61.9%Backtest error
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 index95% low95% high
20250.530.190.87
20260.530.190.87
20270.530.190.88
20280.540.200.88
20290.540.200.88

Northern Harrier Survey Routes in Oregon

Routes recording Northern Harrier in Oregon.
Flook Lake920241994
Princeton619851972
Blitzen 2520241994
Pendleton520241981
Madras420241997
Harney Lake420241993
Warner Vally420241994
Bowden Hills420241999
Mcminnville420241995
Lone Rock320241968
Ordnance319791972
Malheur Nwr319981986
Blitzen319921971
Adair320241981
Sparta319991972
Battle Mtn320241985
Umatilla320221988
Three Forks220242006
Joseph220241975
Eightmile220241982
Blizzard Gap220191984
Fish Lake220241972
Canby220171995
Mikkalo220211999
Crane220241994

Northern Harrier Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradodelawaregeorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomapennsylvaniarhode-islandsouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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