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Species · Nevada · BBS 2026 Release · 1966–2025

Vesper Sparrow Population Trend in Nevada

All statesGrassland birds

Vesper Sparrow in Nevada has surged: up 190% on the route-weighted index since 1971.

+190%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 →
35Routes 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 →
51YearsYears 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 NevadaNotable 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 →

Vesper Sparrow has surged in Nevada: up 190% on the route-weighted index since 1971.

Vesper Sparrow Population Forecast in Nevada

If the recent trend holds, Vesper Sparrow in Nevada is projected to rise about 93% by 2030 — from 5.7 in 2025 to a central estimate of 11 (95% range 4.3–18). A 5-year backtest shows a typical error of ±44.8%, with 100% of held-out values landing inside the 95% band.

+93%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 →
11Projected 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 →
4.3–1895% 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 →
±44.8%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, Vesper Sparrow in Nevada is projected to rise about 93% by 2030 — from 5.7 in 2025 to a central estimate of 11 (95% range 4.3–18). A 5-year backtest shows a typical error of ±44.8%, with 100% 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 →
2026103.817
2027113.917
2028114.117
2029114.217
2030114.318

Vesper Sparrow Survey Routes in Nevada

Routes recording Vesper Sparrow in Nevada.
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 →
Charleston Reservoir9520242024
Ranchogrande6020241988
Humboldt Nf 25920252021
Humboldt Nf5320191993
Dinner Sta3519931968
Sheldon Nwr3020191992
Midas2920251974
Bald Mtn.2920251992
Mizpah1820241988
Jean Lake1319731973
Ruby Valley1120011997
Walker Can1020241968
Austin920182013
Dobbin Creek820181980
Hawthorne820011997
Illipah720151968
Minerva520151988
Gardnerville420111995
Comins Lake320162005
Toiyabe Nf320242003
Cortez220222018
Eureka220221971
Thorne219781978
Willis220141995
Jarbidge220151997

Vesper Sparrow Population Trend in Other States

arizonacaliforniacoloradoconnecticutdelawareidahoillinoisindianaiowakansaskentuckymainemarylandmassachusettsmichiganminnesotamissourimontananebraskanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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