BirdAnalyst
Species · New Mexico · BBS 2025 Release · 1966–2024

Grasshopper Sparrow Population Trend in New Mexico

All statesGrassland birds

Grasshopper Sparrow in New Mexico has surged: up 135% on the route-weighted index since 1974.

+135%Since 1974TrendPercent 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 →
21Routes 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 →
45YearsYears 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 New MexicoNotable 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 →

Grasshopper Sparrow has surged in New Mexico: up 135% on the route-weighted index since 1974.

Grasshopper Sparrow Population Forecast in New Mexico

If the recent trend holds, Grasshopper Sparrow in New Mexico is projected to rise about 65% by 2029 — from 0.28 in 2024 to a central estimate of 0.47 (95% range 0.00–1.0). A 5-year backtest shows a typical error of ±412.1%, with 100% of held-out values landing inside the 95% band.

+65%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 →
0.47Projected 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 →
0.00–1.095% 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 →
±412.1%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 New Mexico is projected to rise about 65% by 2029 — from 0.28 in 2024 to a central estimate of 0.47 (95% range 0.00–1.0). A 5-year backtest shows a typical error of ±412.1%, 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 →
20250.450.000.99
20260.450.001.00
20270.460.001.0
20280.460.001.0
20290.470.001.0

Grasshopper Sparrow Survey Routes in New Mexico

Routes recording Grasshopper Sparrow in New Mexico.
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 →
Farley620241994
Pastura620151994
Floyd420192008
Capulin319941994
Grenville320241968
Caprock320101987
Clovis320241993
Cooley Lake220231993
Maxwell220181997
Gallinas219931993
Rosebud220181994
Bitter Lake219971997
Sabinoso220191980
Lake Valley220071991
Roswell120231987
Sedan120211995
Variadero119991994
Pep120241992
Hobbs120171994
Hatchet Peak120232022
Logan120172017

Grasshopper Sparrow Population Trend in Other States

alabamaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniasouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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