BirdAnalyst
Species · Wyoming · BBS 2025 Release · 1966–2024

Williamson's Sapsucker Population Trend in Wyoming

All statesForest birds

Williamson's Sapsucker in Wyoming has fallen sharply: down 52% on the route-weighted index since 1987.

-52%Since 1987TrendPercent 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 StateSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
36YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Williamson's Sapsucker Trends in WyomingNotable 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 →

Williamson's Sapsucker has fallen sharply in Wyoming: down 52% on the route-weighted index since 1987.

Williamson's Sapsucker Population Forecast in Wyoming

If the recent trend holds, Williamson's Sapsucker in Wyoming is projected to stay roughly flat through 2029, near 0.03 (95% range 0.00–0.08). A 5-year backtest shows a typical error of ±46.8%, with 80% 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 →
0.03Projected 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 →
±46.8%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 Wyoming is projected to stay roughly flat through 2029, near 0.03 (95% range 0.00–0.08). A 5-year backtest shows a typical error of ±46.8%, with 80% of held-out values landing inside the 95% band.19842029
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 →
20250.030.000.08
20260.030.000.08
20270.030.000.08
20280.030.000.08
20290.030.000.08

Williamson's Sapsucker Survey Routes in Wyoming

Routes recording Williamson's Sapsucker in Wyoming.
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 →
Horse Creek220241984
Mammoth220161986
Hunter Peak120091988
Ne Entrance120191998
Moose119991999
Yellowstone119921992
Dubois120211993
Ryan Park120222012
Fiddler Lk120182018
Wilson120162016
Colter Bay 2120212021
Fletcher Pk120092009

Williamson's Sapsucker Population Trend in Other States

arizonacaliforniacoloradoidahomontananevadanew-mexicooregonutahwashington

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