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Species · Arizona · BBS 2025 Release · 1966–2024

Vermilion Flycatcher Population Trend in Arizona

All statesAerial insectivores

Vermilion Flycatcher in Arizona has surged: up 92% on the route-weighted index since 1970.

+92%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 →
31Routes 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 Vermilion Flycatcher 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 →

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 →

Vermilion Flycatcher has surged in Arizona: up 92% on the route-weighted index since 1970.

Vermilion Flycatcher Population Forecast in Arizona

If the recent trend holds, Vermilion Flycatcher in Arizona is projected to fall about 14% by 2029 — from 0.91 in 2024 to a central estimate of 0.79 (95% range 0.07–1.5). A 5-year backtest shows a typical error of ±28.3%, with 80% of held-out values landing inside the 95% band.

-14%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 →
0.79Projected 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 →
0.07–1.595% 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 →
±28.3%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, Vermilion Flycatcher in Arizona is projected to fall about 14% by 2029 — from 0.91 in 2024 to a central estimate of 0.79 (95% range 0.07–1.5). A 5-year backtest shows a typical error of ±28.3%, with 80% 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 →
20250.780.061.5
20260.780.061.5
20270.780.061.5
20280.790.071.5
20290.790.071.5

Vermilion Flycatcher Survey Routes in Arizona

Routes recording Vermilion Flycatcher 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 →
Cutter 23220182015
Pomerene1120241968
Patagonia1120241968
Amado1020231993
Redington720231993
Peña Blanca620241975
Sunizona519971971
Red Rock 2320192015
Araby320232023
Mcneal320182000
Dateland220161990
Skull Valley220242005
Sahuarita220241993
Wickenburg220232017
Dragoon119961993
Portal120181981
Rucker120082008
Wikieup120041992
Laguna119691968
Ajo120081997
San Simon120161974
Palo Verde 2120232017
Cutter120001992
Red Rock120121999
Cabeza Priet120102010

Vermilion Flycatcher Population Trend in Other States

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