BirdAnalyst
Species · BCR 9 · BBS 2026 Release · 1966–2025

Lark Sparrow In Great Basin

All regionsGreat BasinGrassland birds

Lark Sparrow in Great Basin has surged: up 210% on the route-weighted index since 1970.

+210%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 →
209Routes In RegionSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
57YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable SignalsNotable 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 →

Lark Sparrow has surged in Great Basin: up 210% on the route-weighted index since 1970.

Lark Sparrow In Great Basin Population Forecast

If the recent trend holds, Lark Sparrow in Great Basin is projected to fall about 29% by 2030 — from 5.8 in 2025 to a central estimate of 4.1 (95% range 2.6–5.7). A 5-year backtest shows a typical error of ±23.8%, with 60% of held-out values landing inside the 95% band.

-29%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 →
4.1Projected 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 →
2.6–5.795% 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 →
±23.8%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, Lark Sparrow in Great Basin is projected to fall about 29% by 2030 — from 5.8 in 2025 to a central estimate of 4.1 (95% range 2.6–5.7). A 5-year backtest shows a typical error of ±23.8%, with 60% 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 →
20264.02.55.6
20274.12.55.7
20284.12.55.7
20294.12.55.7
20304.12.65.7

Routes In Great Basin

Routes recording Lark Sparrow in Great Basin.
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 →
PromontoryUTAH832025
LeamingtonUTAH752017
Majors PlaceNEVADA582025
Chimney Res.NEVADA492025
Alvord LakeOREGON482025
Trout CreekOREGON482025
WendoverUTAH352011
Catlow RimOREGON312025
Gold HillUTAH302025
GrantsvilleUTAH272025
RanchograndeNEVADA252024
VernonUTAH242025
Three ForksOREGON232025
Jericho JunctionUTAH202025
Pine CreekUTAH192025
AlmoIDAHO182025
Horn RapidsWASHINGTON172024
Glenns FerryIDAHO161986
AdrianOREGON162025
Blitzen 2OREGON162025
Piute MdwsNEVADA152025
Harney LakeOREGON152024
SheavilleOREGON152025
Scootney ReservoirWASHINGTON152025
CrowleyOREGON142025

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