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

White-throated Swift Population Trend in Arizona

All statesAerial insectivores

White-throated Swift in Arizona has declined: down 39% on the route-weighted index since 1970.

-39%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 →
57Routes 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 →
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 White-throated Swift Trends in ArizonaNotable 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 White-throated Swift in Arizona. See the full index history below.

White-throated Swift Population Forecast in Arizona

If the recent trend holds, White-throated Swift in Arizona is projected to stay roughly flat through 2029, near 1.1 (95% range 0.00–2.9). A 5-year backtest shows a typical error of ±58.7%, 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 →
1.1Projected 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 →
0.00–2.995% 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 →
±58.7%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, White-throated Swift in Arizona is projected to stay roughly flat through 2029, near 1.1 (95% range 0.00–2.9). A 5-year backtest shows a typical error of ±58.7%, 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 →
20251.20.003.0
20261.20.003.0
20271.10.003.0
20281.10.003.0
20291.10.002.9

White-throated Swift Survey Routes in Arizona

Routes recording White-throated Swift in Arizona.
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 →
Dateland8220161996
Squaw Peak3519701970
Mormon Lake1919741968
Portal1420241975
Pomerene1420241969
Cutter 21320182015
Many Farms1020052005
Round Rock919761968
Greasewood819931993
Cutter820142014
Florence719711971
Yampai619711969
San Simon620171970
Antares620022002
Ajo 2620222012
Bartlett Res520152002
Blue419901975
Forest Lakes420242023
Sahuarita420231993
Carr Mtn420231985
Hunt319761976
Vicksburg319881988
Ajo320011976
Sunizona319971973
Gila Bend320222000

White-throated Swift Population Trend in Other States

californiacoloradoidahomontananebraskanevadanew-mexicooregonsouth-dakotatexasutahwashingtonwyoming

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