BirdAnalyst
Species · BCR 15 · BBS 2025 Release · 1966–2024

Black-backed Woodpecker In Sierra Nevada

All regionsSierra NevadaForest birds

Black-backed Woodpecker in Sierra Nevada has surged: up 142% on the route-weighted index since 1984.

+142%Since 1984TrendPercent 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 →
16Routes 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 →
28YearsYears 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 →

Black-backed Woodpecker has surged in Sierra Nevada: up 142% on the route-weighted index since 1984.

Forecast

If the recent trend holds, Black-backed Woodpecker in Sierra Nevada is projected to fall about 69% by 2029 — from 0.32 in 2024 to a central estimate of 0.10 (95% range 0.00–0.25). A 5-year backtest shows a typical error of ±52.5%, with 80% of held-out values landing inside the 95% band.

-69%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 →
0.10Projected 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 →
0.00–0.2595% 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, Black-backed Woodpecker in Sierra Nevada is projected to fall about 69% by 2029 — from 0.32 in 2024 to a central estimate of 0.10 (95% range 0.00–0.25). A 5-year backtest shows a typical error of ±52.5%, with 80% of held-out values landing inside the 95% band.19802029
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 →
20250.100.000.24
20260.100.000.24
20270.100.000.24
20280.100.000.24
20290.100.000.25

Routes In Sierra Nevada

Routes recording Black-backed Woodpecker in Sierra Nevada.
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 →
Hat CreekCALIFORNIA32004
Lassen ParkCALIFORNIA21985
SattleyCALIFORNIA21994
LakeshoreCALIFORNIA22024
CrestviewCALIFORNIA22024
ChilcootCALIFORNIA22024
Eagle LakeCALIFORNIA12014
WestvilleCALIFORNIA12013
JohnsvilleCALIFORNIA12015
WoodfordsCALIFORNIA12009
Tuolumne GroveCALIFORNIA12014
Butte MeadowCALIFORNIA12012
GeneseeCALIFORNIA11996
Chaos CraterCALIFORNIA12019
PaxtonCALIFORNIA12011
Little TruckeeCALIFORNIA12001

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