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

Osprey Population Trend in California

All statesGeneralists

Osprey in California has surged: up 117% on the route-weighted index since 1971.

+117%Since 1971
95Routes In State
55Years

Notable Osprey Trends in California

long arc increasecomputed index

Osprey has surged in California: up 117% on the route-weighted index since 1971.

Osprey Population Forecast in California

If the recent trend holds, Osprey in California is projected to rise about 76% by 2029 — from 0.31 in 2024 to a central estimate of 0.55 (95% range 0.27–0.83). A 5-year backtest shows a typical error of ±254.4%, with 0% of held-out values landing inside the 95% band.

+76%Change by 2029
0.55Projected 2029 index
0.27–0.8395% range
±254.4%Backtest error
19692029
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
20250.520.240.80
20260.530.250.81
20270.540.260.82
20280.540.260.82
20290.550.270.83

Osprey Survey Routes in California

Routes recording Osprey in California.
Iron Gate2620191988
Redwood N.P.1520101997
Bodega Bay1220181972
Horse Creek620191970
Hughson520241997
Oroville420242013
Copperopolis420241999
Whiskeytown420132002
Bass Lake320182002
Genesee320241991
Hackamore320032000
Chilcoot320092009
Nubieber220061988
Hullville220181981
Pennington220242008
Westville220171972
Morro Bay219731973
Point Reyes220221973
Shasta Lake220071974
Johnsville220152010
Lake Berryessa220242023
Arvin220152015
Redding219761976
Orleans220111978
Higgins Corn220112011

Osprey Population Trend in Other States

alabamaalaskaarizonaarkansascoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinaohiooregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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