BirdAnalyst
Species · BCR 9 · BBS 2025 Release · 1966–2024

Black Swift In Great Basin

All regionsGreat BasinAerial insectivores

Black Swift in Great Basin has collapsed: down 94% on the route-weighted index since 1970.

-94%Since 1970TrendPercent change in the route-weighted abundance index between a smoothed baseline window and the most recent one. It tracks direction, not absolute population.Full methodology →
18Routes In RegionSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
46YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable SignalsNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

long arc declinecomputed indexTrend sourceWhether the figure is our own computed route-weighted index or an official USGS modeled estimate. The current build labels every trend as computed.Full methodology →

Black Swift has collapsed in Great Basin: down 94% on the route-weighted index since 1970.

Black Swift In Great Basin Population Forecast

If the recent trend holds, Black Swift in Great Basin is projected to stay roughly flat through 2029, near 0.00 (95% range 0.00–1.3). A 5-year backtest shows a typical error of ±1058.4%, with 100% of held-out values landing inside the 95% band.

n/aChange by 2029TrendPercent change in the route-weighted abundance index between a smoothed baseline window and the most recent one. It tracks direction, not absolute population.Full methodology →
0.00Projected 2029 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–1.395% range95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →
±1058.4%Backtest errorBacktest errorTypical error when we hold out the most recent years, forecast them, and compare to what actually happened. Lower means a more trustworthy projection.Full methodology →
If the recent trend holds, Black Swift in Great Basin is projected to stay roughly flat through 2029, near 0.00 (95% range 0.00–1.3). A 5-year backtest shows a typical error of ±1058.4%, with 100% of held-out values landing inside the 95% band.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 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →95% low95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →95% high95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →
20250.000.001.3
20260.000.001.3
20270.000.001.3
20280.000.001.3
20290.000.001.3

Routes In Great Basin

Routes recording Black Swift in Great Basin.
Recent countThe raw number of individuals recorded on this route in its most recent survey year. A single-route tally, not a trend.Full methodology →
IndexWASHINGTON201971
GlacierWASHINGTON102022
L. WenatcheeWASHINGTON102007
Suiattle RivWASHINGTON92003
TwispWASHINGTON52024
CarltonWASHINGTON52019
RimrockWASHINGTON31987
MazamaWASHINGTON32001
RonaldWASHINGTON22017
Lake ChelanWASHINGTON22022
Cascade RivWASHINGTON22003
CedarvilleCALIFORNIA11994
NewhalemWASHINGTON12023
WinthropWASHINGTON12008
LeavenworthWASHINGTON11989
White ChuckWASHINGTON12024
No CascadesWASHINGTON12014
E. Mt. AdamsWASHINGTON11997

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