BirdAnalyst
Species · BCR 4 · BBS 2025 Release · 1966–2024

Spruce Grouse In BCR 4

All regionsBCR 4Generalists

Spruce Grouse in BCR 4 has fallen sharply: down 66% on the route-weighted index since 1995.

-66%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 →
20YearsYears 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 declinecomputed 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 →

Spruce Grouse has fallen sharply in BCR 4: down 66% on the route-weighted index since 1995.

Spruce Grouse In BCR 4 Population Forecast

If the recent trend holds, Spruce Grouse in BCR 4 is projected to stay roughly flat through 2029, near 0.01 (95% range 0.00–0.08). A 5-year backtest shows a typical error of ±88.7%, with 100% of held-out values landing inside the 95% band.

n/aChange 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 →
0.01Projected 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 →
0.00–0.0895% 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 →
±88.7%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, Spruce Grouse in BCR 4 is projected to stay roughly flat through 2029, near 0.01 (95% range 0.00–0.08). A 5-year backtest shows a typical error of ±88.7%, with 100% of held-out values landing inside the 95% band.19862029
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 →
20250.010.000.09
20260.010.000.09
20270.010.000.09
20280.010.000.08
20290.010.000.08

Routes In BCR 4

Routes recording Spruce Grouse in BCR 4.
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 →
TatalinaALASKA22012
CircleALASKA11996
MonahanALASKA12013
WillowALASKA12000
SavageALASKA12016
Chena Hot Spring 2ALASKA12023
Lake LouiseALASKA12003
PetersvilleALASKA11986
Seven LakesALASKA12022
McgrathALASKA11998
Ft. RichrdsnALASKA12008
Mccarthy Rd2ALASKA12024

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