BirdAnalyst
Species · BCR 22 · BBS 2025 Release · 1966–2024

Northern Harrier In Eastern Tallgrass Prairie

All regionsEastern Tallgrass PrairieGeneralists

Northern Harrier in Eastern Tallgrass Prairie has collapsed: down 82% on the route-weighted index since 1968.

-82%Since 1968
131Routes In Region
58Years

Notable Signals

long arc declinecomputed index

Northern Harrier has collapsed in Eastern Tallgrass Prairie: down 82% on the route-weighted index since 1968.

Forecast

If the recent trend holds, Northern Harrier in Eastern Tallgrass Prairie is projected to stay roughly flat through 2029, near 0.02 (95% range 0.00–0.10). A 5-year backtest shows a typical error of ±57.5%, with 100% of held-out values landing inside the 95% band.

n/aChange by 2029
0.02Projected 2029 index
0.00–0.1095% range
±57.5%Backtest error
19662029
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
20250.030.000.10
20260.030.000.10
20270.020.000.10
20280.020.000.10
20290.020.000.10

Routes In Eastern Tallgrass Prairie

Routes recording Northern Harrier in Eastern Tallgrass Prairie.
Mill CreekILLINOIS32010
Grape CreekILLINOIS32007
Cedar ValleyIOWA31990
BloomvilleOHIO32001
HolcombILLINOIS22021
ComptonILLINOIS21972
StreatorILLINOIS22024
PontiacILLINOIS21987
ClarksdaleILLINOIS21995
Mascoutah LkILLINOIS21967
JamestownILLINOIS22023
WalesIOWA21999
LaplandKANSAS21982
Rock CreekKANSAS22002
LakevilleMINNESOTA22000
FrontenacMINNESOTA22017
TrentonMISSOURI22005
NorborneMISSOURI22012
CosmosOHIO21996
W CarrolltonOHIO22004
LondonOHIO22005
RaymondWISCONSIN21980
SheffieldILLINOIS12018
BudaILLINOIS12021
WayneILLINOIS11968

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