Species · Idaho · BBS 2025 Release · 1966–2024

California Gull Population Trend in Idaho

California Gull in Idaho has collapsed: down 94% on the route-weighted index since 1971.

-94%Since 1971
26Routes In State
54Years

Notable California Gull Trends in Idaho

long arc declinecomputed index

California Gull has collapsed in Idaho: down 94% on the route-weighted index since 1971.

California Gull Population Forecast in Idaho

If the recent trend holds, California Gull in Idaho is projected to fall about 100% by 2029 — from 0.44 in 2024 to a central estimate of 0.00 (95% range 0.00–30). A 5-year backtest shows a typical error of ±3575.2%, with 100% of held-out values landing inside the 95% band.

-100%Change by 2029
0.00Projected 2029 index
0.003095% range
±3575.2%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
20250.000.0030
20260.000.0030
20270.000.0030
20280.000.0030
20290.000.0030

California Gull Survey Routes in Idaho

Routes recording California Gull in Idaho.
Henry12319831973
Cascade12019841983
Springfield6520181969
Pocatello3020191979
Blacks Creek2320151987
Mud Lake2220181988
Tractor Flat1120241986
Blackft Res820181984
Glenns Ferry819861986
Craters619961987
Circular Bu520032003
Dubois519901969
Alturas519691969
Acequia320121979
Preston320171988
Cape Horn219971997
Cedar Hill220211990
Kyle Canyon119861986
Leadore120122012
Ririe119961974
Crane Creek119911988
Iron Springs120112005
Featherville120031994
Picabo120141990
Cabarton120001987

California Gull Population Trend in Other States

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