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

Spotted Owl In Sierra Nevada

All regionsSierra NevadaGeneralists

Spotted Owl in Sierra Nevada has collapsed: down 82% on the route-weighted index since 1975.

-82%Since 1975TrendPercent 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 →
6Routes 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 →
15YearsYears 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 →

Spotted Owl has collapsed in Sierra Nevada: down 82% on the route-weighted index since 1975.

Routes In Sierra Nevada

Routes recording Spotted Owl 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 →
Cottage SpgsCALIFORNIA21975
LumberyardCALIFORNIA11989
Greenhorn MtCALIFORNIA11997
Silver CityCALIFORNIA12009
DownievilleCALIFORNIA11987
Pollock PinesCALIFORNIA11999

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