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

Fox Sparrow In Great Basin

All regionsGreat BasinForest birds

Fox Sparrow in Great Basin has held roughly steady: up 10% on the route-weighted index since 1970.

+10%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 →
73Routes 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 →

No notable trend signals for Fox Sparrow in Great Basin. See the full index history below.

Fox Sparrow In Great Basin Population Forecast

If the recent trend holds, Fox Sparrow in Great Basin is projected to fall about 49% by 2030 — from 1.1 in 2025 to a central estimate of 0.57 (95% range 0.00–1.1). A 5-year backtest shows a typical error of ±55.9%, with 60% of held-out values landing inside the 95% band.

-49%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 →
0.57Projected 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 →
0.00–1.195% 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 →
±55.9%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, Fox Sparrow in Great Basin is projected to fall about 49% by 2030 — from 1.1 in 2025 to a central estimate of 0.57 (95% range 0.00–1.1). A 5-year backtest shows a typical error of ±55.9%, 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 →
20260.580.011.1
20270.580.011.1
20280.570.011.1
20290.570.001.1
20300.570.001.1

Routes In Great Basin

Routes recording Fox 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 →
Davis LakeOREGON442025
Magic MtnIDAHO262025
Wizard FallsOREGON222025
BartleCALIFORNIA142021
Crowder FlatCALIFORNIA122018
HawthorneNEVADA122001
Lapham Res.OREGON122025
SistersOREGON112025
Crowley LakeCALIFORNIA72017
Silver CityIDAHO72025
Ruby ValleyNEVADA72001
PauninaOREGON72025
AustinNEVADA62018
MacdoelCALIFORNIA51993
Medicine Mtn.CALIFORNIA42015
Humboldt NfNEVADA42019
Dell SpringOREGON41996
Badger CreekOREGON42025
Hardware RanchUTAH42023
E. Mt. AdamsWASHINGTON42025
Deep SpringsCALIFORNIA32022
NighthawkWASHINGTON31992
Davis CreekCALIFORNIA21984
HackamoreCALIFORNIA22010
SquirrelIDAHO22005

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