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

White-throated Swift Population Trend in California

All statesAerial insectivores

White-throated Swift in California has fallen sharply: down 57% on the route-weighted index since 1970.

-57%Since 1970
136Routes In State
56Years

Notable White-throated Swift Trends in California

long arc declinecomputed index

White-throated Swift has fallen sharply in California: down 57% on the route-weighted index since 1970.

White-throated Swift Population Forecast in California

If the recent trend holds, White-throated Swift in California is projected to fall about 38% by 2029 — from 1.2 in 2024 to a central estimate of 0.71 (95% range 0.00–2.2). A 5-year backtest shows a typical error of ±39.9%, with 100% of held-out values landing inside the 95% band.

-38%Change by 2029
0.71Projected 2029 index
0.00–2.295% range
±39.9%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
20250.810.002.3
20260.780.002.3
20270.760.002.3
20280.730.002.3
20290.710.002.2

White-throated Swift Survey Routes in California

Routes recording White-throated Swift in California.
Kings Canyon3120241972
Angelus Oaks2620171989
Santa Ynez2020191981
Kernville2020082008
Parker Dam1620071975
El Toro1519991995
Coyote1520241972
Copperopolis1320241972
Silver City1120131973
Joshua Tree 21120142014
San Ysidro1020191986
Lake Success1019801972
Fallsvale919811970
Elizabeth Lk920151970
Riovista820192004
Green Valley820221974
Westley820192004
Sawmill Mtn720221970
Lake Hemet719741971
Creston720241972
San Benito Mtn.720092003
Wawona720241998
Lake Cachuma620161974
Hat Creek620002000
Harbor Lake 2620242014

White-throated Swift Population Trend in Other States

arizonacoloradoidahomontananebraskanevadanew-mexicooregonsouth-dakotatexasutahwashingtonwyoming

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