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

Hermit Warbler In Sierra Nevada

All regionsSierra NevadaForest birds

Hermit Warbler in Sierra Nevada has surged: up 109% on the route-weighted index since 1971.

+109%Since 1971
38Routes In Region
55Years

Notable Signals

long arc increasecomputed index

Hermit Warbler has surged in Sierra Nevada: up 109% on the route-weighted index since 1971.

Forecast

If the recent trend holds, Hermit Warbler in Sierra Nevada is projected to stay roughly flat through 2029, near 10 (95% range 5.9–14). A 5-year backtest shows a typical error of ±16.3%, with 80% of held-out values landing inside the 95% band.

+4%Change by 2029
10Projected 2029 index
5.9–1495% range
±16.3%Backtest error
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 index95% low95% high
20259.95.714
2026105.714
2027105.814
2028105.914
2029105.914

Routes In Sierra Nevada

Routes recording Hermit Warbler in Sierra Nevada.
JohnsvilleCALIFORNIA602024
LumberyardCALIFORNIA482024
Butte MeadowCALIFORNIA422014
RivertonCALIFORNIA202023
PlacervilleCALIFORNIA182024
DownievilleCALIFORNIA172024
Meadow ValleyCALIFORNIA112024
WestvilleCALIFORNIA92024
GeneseeCALIFORNIA92024
ChesterCALIFORNIA72017
Forest HillCALIFORNIA62022
StrawberryCALIFORNIA62019
Cottage SpgsCALIFORNIA51975
Bass LakeCALIFORNIA51980
Silver CityCALIFORNIA52013
Forest Hill 2CALIFORNIA52005
Tuolumne GroveCALIFORNIA42024
Tahoe NfCALIFORNIA41994
GoumazCALIFORNIA42009
Pollock PinesCALIFORNIA42024
DardanelleCALIFORNIA32019
Hat CreekCALIFORNIA32018
WawonaCALIFORNIA32024
ChilcootCALIFORNIA32023
Lassen ParkCALIFORNIA21987

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