BirdAnalyst
Species · BCR 15 · BBS 2025 Release · 1966–2024

Lincoln's Sparrow In Sierra Nevada

All regionsSierra NevadaGeneralists

Lincoln's Sparrow in Sierra Nevada has fallen sharply: down 71% on the route-weighted index since 1974.

-71%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 →
12Routes 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 →
51YearsYears 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 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 →

Lincoln's Sparrow has fallen sharply in Sierra Nevada: down 71% on the route-weighted index since 1974.

Forecast

If the recent trend holds, Lincoln's Sparrow in Sierra Nevada is projected to stay roughly flat through 2029, near 0.19 (95% range 0.00–0.57). A 5-year backtest shows a typical error of ±81.3%, with 100% of held-out values landing inside the 95% band.

-9%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 →
0.19Projected 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 →
0.00–0.5795% 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 →
±81.3%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, Lincoln's Sparrow in Sierra Nevada is projected to stay roughly flat through 2029, near 0.19 (95% range 0.00–0.57). A 5-year backtest shows a typical error of ±81.3%, with 100% of held-out values landing inside the 95% band.19722029
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 →
20250.210.000.59
20260.200.000.58
20270.200.000.58
20280.200.000.58
20290.190.000.57

Routes In Sierra Nevada

Routes recording Lincoln's Sparrow in Sierra Nevada.
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 TruckeeCALIFORNIA52023
Butte MeadowCALIFORNIA32014
LakeshoreCALIFORNIA32024
Chaos CraterCALIFORNIA32019
Tuolumne GroveCALIFORNIA22015
DardanelleCALIFORNIA12019
WoodfordsCALIFORNIA12015
Greenhorn MtCALIFORNIA12008
SattleyCALIFORNIA11983
RivertonCALIFORNIA12014
Meadow ValleyCALIFORNIA12013
Pollock PinesCALIFORNIA12024

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