Species · California · BBS 2025 Release · 1966–2024

Black Swift Population Trend in California

Black Swift in California has declined: down 30% on the route-weighted index since 1973.

-30%Since 1973
30Routes In State
39Years

Notable Black Swift Trends in California

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

Black Swift Population Forecast in California

If the recent trend holds, Black Swift in California is projected to stay roughly flat through 2029, near 0.02 (95% range 0.00–0.18). A 5-year backtest shows a typical error of ±74.7%, with 100% of held-out values landing inside the 95% band.

n/aChange by 2029
0.02Projected 2029 index
0.000.1895% range
±74.7%Backtest error
19712029
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
20250.020.000.19
20260.020.000.19
20270.020.000.18
20280.020.000.18
20290.020.000.18

Black Swift Survey Routes in California

Routes recording Black Swift in California.
Yolla Bolly4819801980
Holmes2519991999
Sanger1020182018
Lake Hemet819861972
White River719921973
Cal Hot Spgs720162007
Angelus Oaks520171989
Fallsvale419751975
Rumsey319941994
Jackson319921992
Orange Cove320041977
Waterman Gap320242016
Cohasset319801980
Carmel Val319831983
Lockwood219861973
Lake Success219961972
Coyote219841984
Mt Baldy120151971
Kings Canyon120041974
Fish Rock119781978
Bass Lake120081975
Coulterville119981998
Foster Park119711971
Kernville120082008
Cedarville119941994

Black Swift Population Trend in Other States

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