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

Pine Grosbeak In BCR 4

All regionsBCR 4Generalists

Pine Grosbeak in BCR 4 has fallen sharply: down 66% on the route-weighted index since 1978.

-66%Since 1978TrendPercent 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 →
47Routes 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 →
44YearsYears 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 →

Pine Grosbeak has fallen sharply in BCR 4: down 66% on the route-weighted index since 1978.

Pine Grosbeak In BCR 4 Population Forecast

If the recent trend holds, Pine Grosbeak in BCR 4 is projected to fall about 67% by 2029 — from 0.42 in 2024 to a central estimate of 0.14 (95% range 0.00–1.1). A 5-year backtest shows a typical error of ±52.5%, with 100% of held-out values landing inside the 95% band.

-67%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 →
0.14Projected 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 →
0.00–1.195% 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 →
±52.5%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, Pine Grosbeak in BCR 4 is projected to fall about 67% by 2029 — from 0.42 in 2024 to a central estimate of 0.14 (95% range 0.00–1.1). A 5-year backtest shows a typical error of ±52.5%, with 100% 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 →
20250.230.001.1
20260.210.001.1
20270.180.001.1
20280.160.001.1
20290.140.001.1

Routes In BCR 4

Routes recording Pine Grosbeak 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 →
Unalakleet RiverALASKA82024
Nabesna RoadALASKA71989
Seven LakesALASKA52023
ChistochinaALASKA42023
NorthwayALASKA42016
Swan Lake RdALASKA42023
Kanuti CanynALASKA42004
Anvik RiverALASKA42023
SourdoughALASKA32021
Bear CreekALASKA31988
Nicholai SlALASKA32002
Mt. FairplayALASKA32014
Kobuk River (Short)ALASKA31992
Paxson LakeALASKA31995
CircleALASKA22002
HomerALASKA21982
TonsinaALASKA22018
Anchor RiverALASKA22017
CohoeALASKA22023
KachemakALASKA22024
McgrathALASKA21997
Manley Ht SpALASKA22019
Ft. RichrdsnALASKA22005
Galena (Short)ALASKA22019
Mccarthy Rd2ALASKA22024

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