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Species · BCR 28 · BBS 2025 Release · 1966–2024

Northern Harrier In Appalachian Mountains

All regionsAppalachian MountainsGeneralists

Northern Harrier in Appalachian Mountains has declined: down 49% on the route-weighted index since 1969.

-49%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 →
60Routes In RegionSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
50YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable SignalsNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

No notable trend signals for Northern Harrier in Appalachian Mountains. See the full index history below.

Northern Harrier In Appalachian Mountains Population Forecast

If the recent trend holds, Northern Harrier in Appalachian Mountains is projected to stay roughly flat through 2028, near 0.01 (95% range 0.00–0.04). A 5-year backtest shows a typical error of ±141.2%, with 100% of held-out values landing inside the 95% band.

n/aChange by 2028TrendPercent 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 →
0.01Projected 2028 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.0495% 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 →
±141.2%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, Northern Harrier in Appalachian Mountains is projected to stay roughly flat through 2028, near 0.01 (95% range 0.00–0.04). A 5-year backtest shows a typical error of ±141.2%, with 100% of held-out values landing inside the 95% band.19672028
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 →
20240.010.000.04
20250.010.000.04
20260.010.000.04
20270.010.000.04
20280.010.000.04

Routes In Appalachian Mountains

Routes recording Northern Harrier in Appalachian Mountains.
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 →
GainesvilleNEW-YORK31997
DrydenNEW-YORK22022
CentervilleNEW-YORK21991
Swain 2NEW-YORK22023
WintersetOHIO21967
SheloctaPENNSYLVANIA22017
RydePENNSYLVANIA21992
Kehoe 2KENTUCKY12013
WilliamsportMARYLAND12008
CooperstownNEW-YORK11969
MeridaleNEW-YORK11995
OneontaNEW-YORK11969
OxfordNEW-YORK11974
Vestal CtrNEW-YORK12013
Phillips CrNEW-YORK12013
SwainNEW-YORK12002
East JavaNEW-YORK11987
Oxford 2NEW-YORK12003
DresdenOHIO12001
CumberlandOHIO11979
StonecreekOHIO12002
BirminghamOHIO12011
PetersburgOHIO11999
KeeneOHIO12002
SigelPENNSYLVANIA11995

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