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

Cassin's Finch In Sierra Nevada

All regionsSierra NevadaGeneralists

Cassin's Finch in Sierra Nevada has increased: up 41% on the route-weighted index since 1970.

+41%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 →
33Routes 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 →
56YearsYears 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 Cassin's Finch in Sierra Nevada. See the full index history below.

Cassin's Finch In Sierra Nevada Population Forecast

If the recent trend holds, Cassin's Finch in Sierra Nevada is projected to rise about 120% by 2029 — from 1.6 in 2024 to a central estimate of 3.6 (95% range 0.93–6.3). A 5-year backtest shows a typical error of ±84.2%, with 80% of held-out values landing inside the 95% band.

+120%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 →
3.6Projected 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 →
0.93–6.395% 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 →
±84.2%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, Cassin's Finch in Sierra Nevada is projected to rise about 120% by 2029 — from 1.6 in 2024 to a central estimate of 3.6 (95% range 0.93–6.3). A 5-year backtest shows a typical error of ±84.2%, with 80% 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 →
20253.70.996.3
20263.60.986.3
20273.60.966.3
20283.60.946.3
20293.60.936.3

Routes In Sierra Nevada

Routes recording Cassin's Finch 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 →
ChilcootCALIFORNIA112024
GoumazCALIFORNIA102011
Last ChanceCALIFORNIA102019
Tahoe NfCALIFORNIA91994
DardanelleCALIFORNIA72019
Little TruckeeCALIFORNIA72023
CrestviewCALIFORNIA72024
Lassen ParkCALIFORNIA61989
WoodfordsCALIFORNIA52024
Kings CanyonCALIFORNIA51972
Pine MountainCALIFORNIA52017
SattleyCALIFORNIA42017
RivertonCALIFORNIA42022
ChesterCALIFORNIA42017
PlacervilleCALIFORNIA41999
WestvilleCALIFORNIA32021
JohnsvilleCALIFORNIA32023
Hat CreekCALIFORNIA32018
LakeshoreCALIFORNIA32024
Chaos CraterCALIFORNIA32019
Meadow ValleyCALIFORNIA32023
LumberyardCALIFORNIA22024
Butte MeadowCALIFORNIA22014
PaxtonCALIFORNIA22010
Eagle LakeCALIFORNIA12024

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