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

Willet Population Trend in Utah

All statesShorebirds

Willet in Utah has collapsed: down 87% on the route-weighted index since 1972.

-87%Since 1972TrendPercent 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 →
18Routes 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 →
48YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Willet Trends in UtahNotable 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 →

Willet has collapsed in Utah: down 86% on the route-weighted index since 1972.

Willet Population Forecast in Utah

If the recent trend holds, Willet in Utah is projected to fall about 100% by 2029 — from 0.75 in 2024 to a central estimate of 0.00 (95% range 0.00–4.9). A 5-year backtest shows a typical error of ±155.9%, with 100% of held-out values landing inside the 95% band.

-100%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 →
0.00Projected 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 →
0.00–4.995% 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 →
±155.9%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, Willet in Utah is projected to fall about 100% by 2029 — from 0.75 in 2024 to a central estimate of 0.00 (95% range 0.00–4.9). A 5-year backtest shows a typical error of ±155.9%, with 100% of held-out values landing inside the 95% band.19702029
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 →
20250.000.004.9
20260.000.004.9
20270.000.004.9
20280.000.004.9
20290.000.004.9

Willet Survey Routes in Utah

Routes recording Willet in Utah.
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 →
Snowville3220241999
Neponset Res820181995
E. Bear Lake620221997
Randolph620241992
Timpie Spg520021978
Promontory420241971
Saleratus Cr420171995
Goshen320211970
Callao320191992
Woodruff220232007
Crawford Mts220152004
Leamington120031993
Salt Springs120211986
Gold Hill119871987
Delta120101997
Grantsville120242003
Kamas120242024
Bear River120231992

Willet Population Trend in Other States

alabamacaliforniacoloradoconnecticutdelawarefloridaidaholouisianamainemarylandmassachusettsminnesotamontananebraskanevadanew-jerseynew-yorknorth-carolinanorth-dakotaoregonsouth-carolinasouth-dakotatexasvirginiawyoming

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