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

Cliff Swallow In Sierra Nevada

All regionsSierra NevadaAerial insectivores

Cliff Swallow in Sierra Nevada has held roughly steady: down 1% on the route-weighted index since 1970.

-1%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 →
28Routes 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 Cliff Swallow in Sierra Nevada. See the full index history below.

Forecast

If the recent trend holds, Cliff Swallow in Sierra Nevada is projected to rise about 20% by 2029 — from 20 in 2024 to a central estimate of 24 (95% range 0.00–48). A 5-year backtest shows a typical error of ±109%, with 100% of held-out values landing inside the 95% band.

+20%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 →
24Projected 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 →
0.00–4895% 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 →
±109%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, Cliff Swallow in Sierra Nevada is projected to rise about 20% by 2029 — from 20 in 2024 to a central estimate of 24 (95% range 0.00–48). A 5-year backtest shows a typical error of ±109%, with 100% 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 →
2025240.0048
2026240.0048
2027240.0048
2028240.0048
2029240.0048

Routes In Sierra Nevada

Routes recording Cliff Swallow 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 →
PaxtonCALIFORNIA2152024
SattleyCALIFORNIA762024
ChilcootCALIFORNIA512024
Last ChanceCALIFORNIA502019
GeneseeCALIFORNIA272024
Butte MeadowCALIFORNIA202014
DardanelleCALIFORNIA172019
LakeshoreCALIFORNIA151983
Cottage SpgsCALIFORNIA101975
Little TruckeeCALIFORNIA72023
KernvilleCALIFORNIA72008
Tuolumne GroveCALIFORNIA61979
WoodfordsCALIFORNIA52024
Greenhorn MtCALIFORNIA51980
Meadow ValleyCALIFORNIA42022
Bass LakeCALIFORNIA32016
CoultervilleCALIFORNIA32019
Silver CityCALIFORNIA22013
DownievilleCALIFORNIA22024
RivertonCALIFORNIA22008
Pine MountainCALIFORNIA22017
Lassen ParkCALIFORNIA11982
Eagle LakeCALIFORNIA12019
Kings CanyonCALIFORNIA12002
Higgins CornCALIFORNIA12024

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