BirdAnalyst
Species · BCR 9 · BBS 2025 Release · 1966–2024

Williamson's Sapsucker In Great Basin

All regionsGreat BasinForest birds

Williamson's Sapsucker in Great Basin has surged: up 201% on the route-weighted index since 1971.

+201%Since 1971TrendPercent 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 →
38Routes 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 →
54YearsYears 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 →

Williamson's Sapsucker has surged in Great Basin: up 201% on the route-weighted index since 1971.

Williamson's Sapsucker In Great Basin Population Forecast

If the recent trend holds, Williamson's Sapsucker in Great Basin is projected to rise about 32% by 2029 — from 0.19 in 2024 to a central estimate of 0.25 (95% range 0.14–0.37). A 5-year backtest shows a typical error of ±25.9%, with 100% of held-out values landing inside the 95% band.

+32%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 →
0.25Projected 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 →
0.14–0.3795% 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 →
±25.9%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, Williamson's Sapsucker in Great Basin is projected to rise about 32% by 2029 — from 0.19 in 2024 to a central estimate of 0.25 (95% range 0.14–0.37). A 5-year backtest shows a typical error of ±25.9%, 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 →
20250.240.120.35
20260.240.130.36
20270.250.130.36
20280.250.140.36
20290.250.140.37

Routes In Great Basin

Routes recording Williamson's Sapsucker in Great Basin.
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 →
Barnes ValOREGON111987
SistersOREGON62024
LakeviewOREGON52024
CarltonWASHINGTON52022
Blewett PassWASHINGTON52024
Wizard FallsOREGON42018
E. Mt. AdamsWASHINGTON42024
HackamoreCALIFORNIA32010
Crowley LakeCALIFORNIA22016
Davis LakeOREGON22024
Badger CreekOREGON22023
NubieberCALIFORNIA12002
Davis CreekCALIFORNIA11994
MacdoelCALIFORNIA12011
CedarvilleCALIFORNIA12015
BartleCALIFORNIA12019
TionestaCALIFORNIA12021
Medicine Mtn.CALIFORNIA12021
Magic MtnIDAHO12024
JarbidgeNEVADA12014
Comins LakeNEVADA12008
Dell SpringOREGON11999
Modoc PointOREGON12000
PaisleyOREGON12023
Camp ShermanOREGON11994

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