BirdAnalyst
Species · BCR 5 · BBS 2025 Release · 1966–2024

Acorn Woodpecker In Northern Pacific Rainforest

All regionsNorthern Pacific RainforestForest birds

Acorn Woodpecker in Northern Pacific Rainforest has edged down: down 21% on the route-weighted index since 1970.

-21%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 →
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 →
56YearsYears 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 Acorn Woodpecker in Northern Pacific Rainforest. See the full index history below.

Acorn Woodpecker In Northern Pacific Rainforest Population Forecast

If the recent trend holds, Acorn Woodpecker in Northern Pacific Rainforest is projected to fall about 38% by 2029 — from 1.8 in 2024 to a central estimate of 1.1 (95% range 0.00–2.8). A 5-year backtest shows a typical error of ±37.7%, with 100% of held-out values landing inside the 95% band.

-38%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 →
1.1Projected 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 →
0.00–2.895% 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 →
±37.7%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, Acorn Woodpecker in Northern Pacific Rainforest is projected to fall about 38% by 2029 — from 1.8 in 2024 to a central estimate of 1.1 (95% range 0.00–2.8). A 5-year backtest shows a typical error of ±37.7%, 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 →
20251.30.003.0
20261.20.002.9
20271.20.002.9
20281.20.002.9
20291.10.002.8

Routes In Northern Pacific Rainforest

Routes recording Acorn Woodpecker in Northern Pacific Rainforest.
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 →
AlderpointCALIFORNIA302012
Emigrant Lake 2OREGON262024
Sams ValleyOREGON232024
LongvaleCALIFORNIA222023
UkiahCALIFORNIA222011
Shasta LakeCALIFORNIA202024
Hay ForkCALIFORNIA162017
Emigrant LkOREGON152001
Fish RockCALIFORNIA142014
Burnt RanchCALIFORNIA132016
UmpquaOREGON132024
DerbyOREGON121993
GazelleCALIFORNIA112021
South Fork MtnCALIFORNIA102022
GreenOREGON102024
SelmaOREGON92024
HullvilleCALIFORNIA82019
Junction CtyCALIFORNIA82012
French GulchCALIFORNIA82011
MccloudCALIFORNIA72021
Secret ValOREGON72022
LaytonvilleCALIFORNIA62024
Offield MtnCALIFORNIA52014
KorbelCALIFORNIA52024
Horse CreekCALIFORNIA42019

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