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

Violet-green Swallow In Great Basin

All regionsGreat BasinAerial insectivores

Violet-green Swallow in Great Basin has edged down: down 14% on the route-weighted index since 1970.

-14%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 →
189Routes 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 →
56YearsYears 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 →

No notable trend signals for Violet-green Swallow in Great Basin. See the full index history below.

Violet-green Swallow In Great Basin Population Forecast

If the recent trend holds, Violet-green Swallow in Great Basin is projected to stay roughly flat through 2029, near 3.5 (95% range 1.8–5.2). A 5-year backtest shows a typical error of ±14.5%, with 100% of held-out values landing inside the 95% band.

+5%Change 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 →
3.5Projected 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 →
1.8–5.295% 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 →
±14.5%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, Violet-green Swallow in Great Basin is projected to stay roughly flat through 2029, near 3.5 (95% range 1.8–5.2). A 5-year backtest shows a typical error of ±14.5%, 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 →
20253.51.75.2
20263.51.85.2
20273.51.85.2
20283.51.85.2
20293.51.85.2

Routes In Great Basin

Routes recording Violet-green 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 →
TwispWASHINGTON992024
OrdnanceOREGON691978
Meadow VallyNEVADA602024
LeavenworthWASHINGTON372024
HyrumUTAH331979
NewhalemWASHINGTON332024
Hardware RanchUTAH282018
Pine CreekUTAH252013
Magic MtnIDAHO242024
RanchograndeNEVADA221991
YakimaWASHINGTON212024
SelahWASHINGTON202019
ReardanWASHINGTON192024
IngallsCALIFORNIA171973
SnowdenWASHINGTON172024
EllensburgWASHINGTON162024
Mt HoodOREGON132024
Malheur NwrOREGON131991
Dougal ResIDAHO122024
L. WenatcheeWASHINGTON122023
LikelyCALIFORNIA112019
ImnahaOREGON112024
BickletonWASHINGTON112019
Rye PatchNEVADA101974
Catlow RimOREGON102016

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