BirdAnalyst
Species · BCR 10 · BBS 2026 Release · 1966–2025

Osprey In Northern Rockies

All regionsNorthern RockiesBirds of prey

Osprey in Northern Rockies has surged: up 81% on the route-weighted index since 1970.

+81%Since 1970TrendPercent 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 →
114Routes 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 →
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 SignalsNotable 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 →

Osprey has surged in Northern Rockies: up 81% on the route-weighted index since 1970.

Osprey In Northern Rockies Population Forecast

If the recent trend holds, Osprey in Northern Rockies is projected to rise about 15% by 2030 — from 0.34 in 2025 to a central estimate of 0.39 (95% range 0.17–0.61). A 5-year backtest shows a typical error of ±45.8%, with 100% of held-out values landing inside the 95% band.

+15%Change by 2030TrendPercent 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 →
0.39Projected 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.17–0.6195% 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 →
±45.8%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, Osprey in Northern Rockies is projected to rise about 15% by 2030 — from 0.34 in 2025 to a central estimate of 0.39 (95% range 0.17–0.61). A 5-year backtest shows a typical error of ±45.8%, with 100% of held-out values landing inside the 95% band.19682030
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 →
20260.380.160.60
20270.380.160.60
20280.390.170.61
20290.390.170.61
20300.390.170.61

Routes In Northern Rockies

Routes recording Osprey in Northern Rockies.
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 →
CascadeIDAHO131984
WilsonWYOMING62025
Willow Creek 2MONTANA42025
Hebgen LakeMONTANA42025
SpartaOREGON42025
NezperceIDAHO32012
CentervilleIDAHO32025
CabartonIDAHO32024
LaurierWASHINGTON32022
MammothWYOMING32010
AlpineWYOMING32025
Horse CreekWYOMING32025
MaybellCOLORADO22025
NaplesIDAHO22021
Lolo PassIDAHO22014
Cape HornIDAHO22024
CoolinIDAHO22021
Sawtooth CtyIDAHO22009
PierceIDAHO21992
FeathervilleIDAHO22025
Rochat DivdeIDAHO22025
Libby DamMONTANA22012
KalispellMONTANA22025
St MaryMONTANA22007
ClintonMONTANA22025

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.