BirdAnalyst
Species · BCR 9 · BBS 2026 Release · 1966–2025

Cliff Swallow In Great Basin

All regionsGreat BasinAerial insectivores

Cliff Swallow in Great Basin has surged: up 93% on the route-weighted index since 1970.

+93%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 →
219Routes 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 →
57YearsYears 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 increasecomputed 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 →

Cliff Swallow has surged in Great Basin: up 93% on the route-weighted index since 1970.

Cliff Swallow In Great Basin Population Forecast

If the recent trend holds, Cliff Swallow in Great Basin is projected to rise about 71% by 2030 — from 27 in 2025 to a central estimate of 47 (95% range 19–75). A 5-year backtest shows a typical error of ±138.3%, with 0% of held-out values landing inside the 95% band.

+71%Change by 2030TrendPercent 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 →
47Projected 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
19–7595% 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 →
±138.3%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, Cliff Swallow in Great Basin is projected to rise about 71% by 2030 — from 27 in 2025 to a central estimate of 47 (95% range 19–75). A 5-year backtest shows a typical error of ±138.3%, with 0% of held-out values landing inside the 95% band.19682030
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 →
2026461874
2027461874
2028461974
2029471975
2030471975

Routes In Great Basin

Routes recording Cliff Swallow 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 →
DorrisCALIFORNIA19162019
Bear RiverUTAH6682025
Modoc PointOREGON5382018
Scootney ReservoirWASHINGTON3842025
Iron GateCALIFORNIA3812019
PromontoryUTAH3722025
GardnervilleNEVADA2672012
HenryIDAHO2041983
Columbia NwrWASHINGTON1982022
MesaWASHINGTON1852008
OthelloWASHINGTON1721991
BridgeportCALIFORNIA1611977
NubieberCALIFORNIA1602018
Willow SpgOREGON1521971
Horn RapidsWASHINGTON1382024
YakimaWASHINGTON1312025
LeamingtonUTAH1302017
Comins LakeNEVADA1252016
RirieIDAHO1232025
FallonNEVADA1232025
PotholesWASHINGTON1232023
RavendaleCALIFORNIA1192025
Daniels ResIDAHO1162025
LynnUTAH1162025
Crowley LakeCALIFORNIA1132025

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.