BirdAnalyst
Species · BCR 10 · BBS 2026 Release · 1966–2025

White-throated Swift In Northern Rockies

All regionsNorthern RockiesAerial insectivores

White-throated Swift in Northern Rockies has surged: up 429% on the route-weighted index since 1973.

+429%Since 1973TrendPercent 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 →
39Routes 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 →
49YearsYears 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 →

White-throated Swift has surged in Northern Rockies: up 429% on the route-weighted index since 1973.

White-throated Swift In Northern Rockies Population Forecast

If the recent trend holds, White-throated Swift in Northern Rockies is projected to fall about 29% by 2030 — from 0.62 in 2025 to a central estimate of 0.44 (95% range 0.17–0.71). A 5-year backtest shows a typical error of ±70.2%, with 100% of held-out values landing inside the 95% band.

-29%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 →
0.44Projected 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 →
0.17–0.7195% 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 →
±70.2%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 Northern Rockies is projected to fall about 29% by 2030 — from 0.62 in 2025 to a central estimate of 0.44 (95% range 0.17–0.71). A 5-year backtest shows a typical error of ±70.2%, with 100% of held-out values landing inside the 95% band.19692030
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 →
20260.410.150.68
20270.420.150.69
20280.430.160.69
20290.430.170.70
20300.440.170.71

Routes In Northern Rockies

Routes recording White-throated Swift in Northern Rockies.
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 →
Pryor Mtn.MONTANA312025
LimaMONTANA302025
MeeteetseWYOMING232025
Cramer CreekMONTANA122016
LovellWYOMING121997
Willow CreekMONTANA101980
Pagil GulchMONTANA102025
CurlewWASHINGTON62013
St RegisMONTANA52018
GeboWYOMING52023
ArleeMONTANA31969
Fort LoganMONTANA32023
TensleepWYOMING32015
Salmon RiverIDAHO22023
Willow Creek 2MONTANA22022
VictorMONTANA22019
MadrasOREGON22001
MammothWYOMING21986
ClarkWYOMING21990
SunbeamIDAHO12025
FeathervilleIDAHO11992
PolsonMONTANA12014
Painted RockMONTANA12000
BridgeportOREGON12022
RandolphUTAH12023

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