BirdAnalyst
Species · Wyoming · BBS 2026 Release · 1966–2025

Brewer's Sparrow Population Trend in Wyoming

All statesArid-land birds

Brewer's Sparrow in Wyoming has increased: up 47% on the route-weighted index since 1970.

+47%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 →
132Routes 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 →
57YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Brewer's Sparrow 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 →

No notable trend signals for Brewer's Sparrow in Wyoming. See the full index history below.

Brewer's Sparrow Population Forecast in Wyoming

If the recent trend holds, Brewer's Sparrow in Wyoming is projected to fall about 20% by 2030 — from 18 in 2025 to a central estimate of 15 (95% range 4.3–25). A 5-year backtest shows a typical error of ±29%, with 80% of held-out values landing inside the 95% band.

-20%Change by 2030TrendPercent 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 →
15Projected 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
4.3–2595% 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 →
±29%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, Brewer's Sparrow in Wyoming is projected to fall about 20% by 2030 — from 18 in 2025 to a central estimate of 15 (95% range 4.3–25). A 5-year backtest shows a typical error of ±29%, with 80% of held-out values landing inside the 95% band.19682030
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 →
2026154.425
2027154.425
2028154.325
2029154.325
2030154.325

Brewer's Sparrow Survey Routes in Wyoming

Routes recording Brewer's Sparrow 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 →
Seedskadee 212620242024
Ryegrass12220251994
Mckinnon8619861969
Bucknum7720241993
Reliance7420251977
Lamont7020251987
Meeteetse6520251992
Bear Creek6420251968
Patrick Draw6319801973
Elk Horn 26320252022
Flamin Gorge6320251988
Bairoil6220251988
Big Sandy6120251988
Diamondville6019821977
Nowood5320251988
Moran5120162002
Daniel4919881980
Black Rock 24720252010
Rawlins 24620252015
Savageton4420252019
Patrick Draw 54320092004
Mammoth4120251982
Anchor4120181993
Patrick Draw 24019831981
Boulder3920251982

Brewer's Sparrow Population Trend in Other States

arizonacaliforniacoloradoidahokansasmontananebraskanevadanew-mexiconorth-dakotaoklahomaoregonsouth-dakotatexasutahwashington

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.