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

Lincoln's Sparrow Population Trend in California

All statesGeneralists

Lincoln's Sparrow in California has declined: down 46% on the route-weighted index since 1973.

-46%Since 1973TrendPercent 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 →
22Routes 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 →
53YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Lincoln's Sparrow Trends in CaliforniaNotable 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 Lincoln's Sparrow in California. See the full index history below.

Lincoln's Sparrow Population Forecast in California

If the recent trend holds, Lincoln's Sparrow in California is projected to stay roughly flat through 2029, near 0.06 (95% range 0.00–0.12). A 5-year backtest shows a typical error of ±157.6%, with 100% of held-out values landing inside the 95% band.

n/aChange 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 →
0.06Projected 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 →
0.00–0.1295% 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 →
±157.6%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, Lincoln's Sparrow in California is projected to stay roughly flat through 2029, near 0.06 (95% range 0.00–0.12). A 5-year backtest shows a typical error of ±157.6%, with 100% of held-out values landing inside the 95% band.19702029
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 →
20250.060.000.12
20260.060.000.12
20270.060.000.12
20280.060.000.12
20290.060.000.12

Lincoln's Sparrow Survey Routes in California

Routes recording Lincoln's Sparrow in California.
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 →
Little Truckee520231997
Big Bear419861970
Butte Meadow320141981
Chaos Crater320191999
Lakeshore320241975
Dirigio220121999
Tuolumne Grove220151972
Mccloud219791979
Offield Mtn220141976
Green Valley119771977
Dardanelle120191975
Whiskeytown120052005
Sattley119831983
Meadow Valley120132013
Pollock Pines120242000
Mt Pinos119861979
Riverton120141973
Deep Springs120192019
Rio Dell119871987
Woodfords120151972
Greenhorn Mt120081984
Valyermo120152015

Lincoln's Sparrow Population Trend in Other States

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