BirdAnalyst
Species · Utah · BBS 2025 Release · 1966–2024

White-throated Swift Population Trend in Utah

All statesAerial insectivores

White-throated Swift in Utah has collapsed: down 75% on the route-weighted index since 1972.

-75%Since 1972TrendPercent 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 →
54Routes In StateSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
52YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable White-throated Swift Trends in UtahNotable 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 →

White-throated Swift has collapsed in Utah: down 75% on the route-weighted index since 1972.

White-throated Swift Population Forecast in Utah

If the recent trend holds, White-throated Swift in Utah is projected to rise about 62% by 2029 — from 0.75 in 2024 to a central estimate of 1.2 (95% range 0.00–4.7). A 5-year backtest shows a typical error of ±158.2%, with 100% of held-out values landing inside the 95% band.

+62%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 →
1.2Projected 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 →
0.00–4.795% 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 →
±158.2%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, White-throated Swift in Utah is projected to rise about 62% by 2029 — from 0.75 in 2024 to a central estimate of 1.2 (95% range 0.00–4.7). A 5-year backtest shows a typical error of ±158.2%, 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 →
20251.40.004.9
20261.30.004.8
20271.30.004.8
20281.20.004.7
20291.20.004.7

White-throated Swift Survey Routes in Utah

Routes recording White-throated Swift in Utah.
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 →
Arches Np9620111989
La Sal3619991996
Wellington3220021997
Castleton2919851977
Shivwitz1720241992
Gilson Butte1220042000
Canyonlands1120061991
Cleveland1120241994
Boulder1020181974
Canyonlands1020221986
Hite720211986
Hanksville620101996
Kamas620182015
Hardware Ranch620182018
Navajo Lake520021968
Cane Spr Des519971994
Lost Cr. Res320152015
Altonah319781971
Book Ridge320232003
Bryce Canyon320241990
Beaver320241971
Aneth320141986
Hatch320242000
Alton320031998
Glen Canyon320241994

White-throated Swift Population Trend in Other States

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