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

Grasshopper Sparrow Population Trend in Utah

All statesGrassland birds

Grasshopper Sparrow in Utah has fallen sharply: down 62% on the route-weighted index since 1988.

-62%Since 1988TrendPercent 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 →
20Routes 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 →
36YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Grasshopper Sparrow 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 →

Grasshopper Sparrow has fallen sharply in Utah: down 62% on the route-weighted index since 1988.

Grasshopper Sparrow Population Forecast in Utah

If the recent trend holds, Grasshopper Sparrow in Utah is projected to fall about 100% by 2029 — from 0.15 in 2024 to a central estimate of 0.00 (95% range 0.00–0.45). A 5-year backtest shows a typical error of ±62.3%, 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 →
0.00–0.4595% 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 →
±62.3%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, Grasshopper Sparrow in Utah is projected to fall about 100% by 2029 — from 0.15 in 2024 to a central estimate of 0.00 (95% range 0.00–0.45). A 5-year backtest shows a typical error of ±62.3%, with 100% of held-out values landing inside the 95% band.19742029
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 →
20250.040.000.48
20260.030.000.47
20270.020.000.47
20280.010.000.46
20290.000.000.45

Grasshopper Sparrow Survey Routes in Utah

Routes recording Grasshopper Sparrow 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 →
Altonah5219931993
Johnson Can720241987
Notch Peak319921992
Promontory220241974
Snowville220231999
Kamas219981998
Vernal220181999
Gold Hill220011996
Neponset Res120122002
Saleratus Cr120092000
E. Bear Lake120221997
Lynn120101994
Randolph120082008
Grouse Creek120102010
Vernon120182016
Bear River120152015
Indian Peak119951995
Alton119971997
Heber Mtn.120121998
Jensen120221992

Grasshopper Sparrow Population Trend in Other States

alabamaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniasouth-carolinasouth-dakotatennesseetexasvermontvirginiawashingtonwest-virginiawisconsinwyoming

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