Species · Indiana · BBS 2025 Release · 1966–2024

Northern Harrier Population Trend in Indiana

Northern Harrier in Indiana has fallen sharply: down 65% on the route-weighted index since 1971.

-65%Since 1971
23Routes In State
30Years

Notable Northern Harrier Trends in Indiana

long arc declinecomputed index

Northern Harrier has fallen sharply in Indiana: down 65% on the route-weighted index since 1971.

Northern Harrier Population Forecast in Indiana

If the recent trend holds, Northern Harrier in Indiana is projected to stay roughly flat through 2029, near 0.03 (95% range 0.00–0.10). A 5-year backtest shows a typical error of ±52.4%, with 100% of held-out values landing inside the 95% band.

n/aChange by 2029
0.03Projected 2029 index
0.000.1095% range
±52.4%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
20270.030.000.10
20280.030.000.10
20290.030.000.10

Northern Harrier Survey Routes in Indiana

Routes recording Northern Harrier in Indiana.
Hebron120142014
Kankakee Sands120232004
Ellis120151970
Fowler120041966
W Lafayette120111985
Galveston119911991
Middletown119881988
Swayzee120192019
Berne119871983
Pimento119981998
Brazil120152000
Jamestown120192019
Sexton120241991
Milroy120042000
Shelbyville120102010
Washington119871987
Millersburg120052003
Indian Spgs119971997
Evansville120022002
Crown Point120001999
Newberry120192005
Cyprss120052005
Kokomo120152015

Northern Harrier Population Trend in Other States

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