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

Vesper Sparrow Population Trend in Wyoming

All statesGrassland birds

Vesper Sparrow in Wyoming has increased: up 34% on the route-weighted index since 1970.

+34%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 →
138Routes 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 →
56YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Vesper 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 Vesper Sparrow in Wyoming. See the full index history below.

Vesper Sparrow Population Forecast in Wyoming

If the recent trend holds, Vesper Sparrow in Wyoming is projected to stay roughly flat through 2029, near 20 (95% range 13–27). A 5-year backtest shows a typical error of ±18.3%, with 100% of held-out values landing inside the 95% band.

+8%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 →
20Projected 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 →
13–2795% 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 →
±18.3%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, Vesper Sparrow in Wyoming is projected to stay roughly flat through 2029, near 20 (95% range 13–27). A 5-year backtest shows a typical error of ±18.3%, 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 →
2025201326
2026201326
2027201326
2028201327
2029201327

Vesper Sparrow Survey Routes in Wyoming

Routes recording Vesper 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 →
Bairoil10420241988
Lamont7620241987
Meeteetse7220241998
Baggs6620241995
Ryegrass6520241990
Sybille Cyn6220241980
Seedskadee 26120242024
Boulder5520241982
Ne Entrance5020211982
Meadowdale4720141983
Mtn View4420241980
Moran4420162002
Ervay4220241973
Walcott4020241982
Bucknum3820241993
Ethete3720241991
Harmony3720231980
Clark3620241990
Seely3520001990
Pathfinder3520241982
Nowood3420241988
Buford3420241974
Crowheart3420211987
Sand Draw3220241994
Gas Hills3120121991

Vesper Sparrow Population Trend in Other States

arizonacaliforniacoloradoconnecticutdelawareidahoillinoisindianaiowakansaskentuckymainemarylandmassachusettsmichiganminnesotamissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsin

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