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Species · California · BBS 2025 Release · 1966–2024

California Thrasher Population Trend in California

All statesGeneralists

California Thrasher in California has held roughly steady: down 4% on the route-weighted index since 1970.

-4%Since 1970
115Routes In State
56Years

Notable California Thrasher Trends in California

No notable trend signals for California Thrasher in California. See the full index history below.

California Thrasher Population Forecast in California

If the recent trend holds, California Thrasher in California is projected to fall about 54% by 2029 — from 1.7 in 2024 to a central estimate of 0.79 (95% range 0.00–1.9). A 5-year backtest shows a typical error of ±60.8%, with 60% of held-out values landing inside the 95% band.

-54%Change by 2029
0.79Projected 2029 index
0.00–1.995% range
±60.8%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
20250.850.002.0
20260.830.002.0
20270.820.002.0
20280.810.002.0
20290.790.001.9

California Thrasher Survey Routes in California

Routes recording California Thrasher in California.
Elsinore Mtn4120241970
Lake Cachuma3720161972
Cuyamaca Pk2720241970
Rumsey1920081969
Mt Baldy1820241970
Oak Grove1620241968
Poway1219801973
Lockwood Val1120191970
Anza1120041970
Colma1019711968
Jacumba1020241973
Anza 21020242005
Cleveland Nf 21020222019
Fallsvale819811974
Elizabeth Lk720161970
Yolla Bolly720241973
Hough Springs720071999
Folsom620241984
Mesa Grande620241970
Greenfield620241973
Tomhead620111998
Stonyford620182015
Foster Park519941969
Green Valley520231972
Tres Pinos 2520112005

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