BirdAnalyst
Species · BCR 10 · BBS 2025 Release · 1966–2024

Gray Partridge In Northern Rockies

All regionsNorthern RockiesGeneralists

Gray Partridge in Northern Rockies has risen sharply: up 59% on the route-weighted index since 1973.

+59%Since 1973TrendPercent 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 →
25Routes 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 →
46YearsYears 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 →

Gray Partridge has risen sharply in Northern Rockies: up 59% on the route-weighted index since 1973.

Gray Partridge In Northern Rockies Population Forecast

If the recent trend holds, Gray Partridge in Northern Rockies is projected to fall about 72% by 2029 — from 0.23 in 2024 to a central estimate of 0.07 (95% range 0.00–0.17). A 5-year backtest shows a typical error of ±86.7%, with 60% of held-out values landing inside the 95% band.

-72%Change by 2029TrendPercent 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 →
0.07Projected 2029 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.1795% 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 →
±86.7%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, Gray Partridge in Northern Rockies is projected to fall about 72% by 2029 — from 0.23 in 2024 to a central estimate of 0.07 (95% range 0.00–0.17). A 5-year backtest shows a typical error of ±86.7%, with 60% of held-out values landing inside the 95% band.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 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 →
20250.070.000.17
20260.070.000.17
20270.070.000.17
20280.070.000.17
20290.070.000.17

Routes In Northern Rockies

Routes recording Gray Partridge 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 →
Clyde ParkMONTANA122024
WorlandWYOMING92024
PolsonMONTANA62024
Pablo Res.MONTANA52005
LaurelMONTANA32019
Crane CreekIDAHO22010
AugustaMONTANA21989
BoulderMONTANA22024
Willow CreekMONTANA21976
Wise RiverMONTANA22000
GlenMONTANA22021
Willow Creek 2MONTANA22024
Church HillMONTANA22024
Threemile WaMONTANA22021
CodyWYOMING22013
NowoodWYOMING22009
ClarkWYOMING21991
LeoWYOMING22016
KalispellMONTANA12009
St MaryMONTANA12007
ChestnutMONTANA12015
Wolf CreekMONTANA12018
WickiupOREGON11970
CloverlandWASHINGTON12014
LamontWYOMING12000

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