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

Vesper Sparrow Population Trend in Colorado

All statesGrassland birds

Vesper Sparrow in Colorado has surged: up 19× on the route-weighted index since 1970.

19×Since 1970
124Routes In State
56Years

Notable Vesper Sparrow Trends in Colorado

long arc increasecomputed index

Vesper Sparrow has surged in Colorado: up 19× on the route-weighted index since 1970.

Vesper Sparrow Population Forecast in Colorado

If the recent trend holds, Vesper Sparrow in Colorado is projected to rise about 13% by 2029 — from 8.6 in 2024 to a central estimate of 9.7 (95% range 5.3–14). A 5-year backtest shows a typical error of ±17.9%, with 100% of held-out values landing inside the 95% band.

+13%Change by 2029
9.7Projected 2029 index
5.3–1495% range
±17.9%Backtest error
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 index95% low95% high
20259.44.914
20269.55.014
20279.55.114
20289.65.214
20299.75.314

Vesper Sparrow Survey Routes in Colorado

Routes recording Vesper Sparrow in Colorado.
Walden7320241990
Great Divide6220241974
Gribbles Prk5720241995
Dinosaur4720241995
Maybell3920241971
Yellowjacket Pass3720241998
San Luis3420241991
Uncompahgre2820241988
Mcphee Res.2820241996
Lay2720241996
Doyleville2620241988
Angora2420241998
Mesita2420242005
Yampa2320231969
Blanca2319871980
Antonito2220041995
Gardner2220241998
Browns Park2120241992
Westcliffe2120241999
Wray Gulch1820231988
Powderhorn1820231995
Piedra1720241992
Guffey1620241991
Moffat1520241970
Como1520241996

Vesper Sparrow Population Trend in Other States

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

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