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

Spruce Grouse In Northern Rockies

All regionsNorthern RockiesGeneralists

Spruce Grouse in Northern Rockies has fallen sharply: down 54% on the route-weighted index since 1995.

-54%Since 1995TrendPercent 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 →
12Routes 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 →
18YearsYears 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 Spruce Grouse in Northern Rockies. See the full index history below.

Spruce Grouse In Northern Rockies Population Forecast

If the recent trend holds, Spruce Grouse in Northern Rockies is projected to stay roughly flat through 2021, near 0.01 (95% range 0.00–0.04). A 5-year backtest shows a typical error of ±87%, with 80% of held-out values landing inside the 95% band.

n/aChange by 2021TrendPercent 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 2021 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 →
±87%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, Spruce Grouse in Northern Rockies is projected to stay roughly flat through 2021, near 0.01 (95% range 0.00–0.04). A 5-year backtest shows a typical error of ±87%, with 80% of held-out values landing inside the 95% band.19782021
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 →
20170.010.000.04
20180.010.000.04
20190.010.000.04
20200.010.000.04
20210.010.000.04

Routes In Northern Rockies

Routes recording Spruce Grouse 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 →
ArleeMONTANA21995
Logan PassMONTANA21995
GreenoughMONTANA22004
MivodenIDAHO11989
Lolo PassIDAHO12012
BurgdorfIDAHO12015
Yellow PineIDAHO12016
St RegisMONTANA11998
SulaMONTANA12007
Skalkho-RyeMONTANA12005
Inside RoadMONTANA12005
Sullivan Lake 2WASHINGTON12016

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