BirdAnalyst
Species · California · BBS 2025 Release · 1966–2024

Loggerhead Shrike Population Trend in California

All statesGeneralists

Loggerhead Shrike in California has collapsed: down 88% on the route-weighted index since 1970.

-88%Since 1970
156Routes In State
56Years

Notable Loggerhead Shrike Trends in California

long arc declinecomputed index

Loggerhead Shrike has collapsed in California: down 88% on the route-weighted index since 1970.

Loggerhead Shrike Population Forecast in California

If the recent trend holds, Loggerhead Shrike in California is projected to fall about 100% by 2029 — from 0.88 in 2024 to a central estimate of 0.00 (95% range 0.00–2.4). A 5-year backtest shows a typical error of ±116.8%, with 100% of held-out values landing inside the 95% band.

-100%Change by 2029
0.00Projected 2029 index
0.00–2.495% range
±116.8%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
20250.000.002.4
20260.000.002.4
20270.000.002.4
20280.000.002.4
20290.000.002.4

Loggerhead Shrike Survey Routes in California

Routes recording Loggerhead Shrike in California.
Shafter1819891971
Onyx1720151968
Blythe1719791973
Tranquillity1620041972
Atwater1420121972
Goldstone1320091968
Ravendale1320241973
Riovista1120241968
Ventucopa1120021972
Willow Spgs1019811968
Valley Wells920231969
Havasu Lake819781973
Buena Vista720191990
S Catalina620191989
Maricopa620241970
Hollister 2620242012
Hollister520111974
Elizabeth Lk519841970
Carrizo Pln520231970
Ora Loma520241972
Cal Hot Spgs519941993
Tracy 2520242010
Colma419681968
Big Pine420051970
Moreno420241968

Loggerhead Shrike Population Trend in Other States

alabamaarizonaarkansascoloradofloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmichiganminnesotamississippimissourimontananebraskanevadanew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniasouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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