BirdAnalyst
Species · BCR 16 · BBS 2025 Release · 1966–2024

Violet-green Swallow In Southern Rockies / Colorado Plateau

All regionsSouthern Rockies / Colorado PlateauAerial insectivores

Violet-green Swallow in Southern Rockies / Colorado Plateau has increased: up 36% on the route-weighted index since 1970.

+36%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 →
228Routes 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 Southern Rockies / Colorado Plateau. See the full index history below.

Violet-green Swallow In Southern Rockies / Colorado Plateau Population Forecast

If the recent trend holds, Violet-green Swallow in Southern Rockies / Colorado Plateau is projected to stay roughly flat through 2029, near 9.7 (95% range 3.8–16). A 5-year backtest shows a typical error of ±37.7%, with 100% of held-out values landing inside the 95% band.

+9%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 →
9.7Projected 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 →
3.8–1695% 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 →
±37.7%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 Southern Rockies / Colorado Plateau is projected to stay roughly flat through 2029, near 9.7 (95% range 3.8–16). A 5-year backtest shows a typical error of ±37.7%, 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 →
20259.63.815
20269.63.815
20279.63.815
20289.63.815
20299.73.816

Routes In Southern Rockies / Colorado Plateau

Routes recording Violet-green Swallow in Southern Rockies / Colorado Plateau.
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 →
AspenCOLORADO892024
Dry ParkARIZONA682024
Colona 2COLORADO612021
BufordCOLORADO602024
Dolores RivCOLORADO592024
CokedaleCOLORADO572024
Stillwater PassCOLORADO402009
GallinasNEW-MEXICO402024
Bryce CanyonUTAH372024
Pagosa SpgsCOLORADO351982
BoulderUTAH342021
ColonaCOLORADO332014
Dunckley PasCOLORADO332024
Fox CreekCOLORADO292024
La SalUTAH292000
Gold Hill 2COLORADO282024
Ojo SarcoNEW-MEXICO272024
ParlinCOLORADO262023
Gold HillCOLORADO262012
Lizard Head PassCOLORADO262024
CanyonlandsUTAH262006
TsaileARIZONA242023
Lake City 2COLORADO232024
Mcphee Res.COLORADO232024
Cheesman LkCOLORADO222024

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