BirdAnalyst
Species · BBS 2026 Release · 1966–2025

Ash-throated Flycatcher Population Analysis

TyrannidaeAerial insectivoresMyiarchus cinerascens

Ash-throated Flycatcher has surged: up 327% on the route-weighted index since 1969.

+327%Since 1969TrendPercent 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 →
802RoutesSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
58Years SurveyedYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

About the Ash-throated Flycatcher

The Ash-throated Flycatcher (Myiarchus cinerascens) is a North American member of the Tyrant Flycatchers (Tyrannidae). In this analysis it is grouped with the aerial insectivores.

Size
4.5–9 in long (12–23 cm) — a small to medium flycatcher (typical for the family)
Habitat
Open airspace over fields, water and towns; nests in cavities, earthen banks or on structures.
Diet
Flying insects caught on the wing.
Range
Recorded on 802 Breeding Bird Survey routes across 13 states, most concentrated in the Southern Rockies / Colorado Plateau.
Family
Tyrannidae · Aerial insectivores

Notable Ash-throated Flycatcher TrendsNotable 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 →

Ash-throated Flycatcher has surged in surveyed states: up 327% on the route-weighted index since 1969.

Ash-throated Flycatcher Population Forecast

If the recent trend holds, Ash-throated Flycatcher is projected to rise about 14% by 2030 — from 1.5 in 2025 to a central estimate of 1.7 (95% range 1.3–2.1). A 5-year backtest shows a typical error of ±16.5%, with 100% of held-out values landing inside the 95% band.

+14%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 →
1.7Projected 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 →
1.3–2.195% 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 →
±16.5%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, Ash-throated Flycatcher is projected to rise about 14% by 2030 — from 1.5 in 2025 to a central estimate of 1.7 (95% range 1.3–2.1). A 5-year backtest shows a typical error of ±16.5%, with 100% of held-out values landing inside the 95% band.19672030
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 →
20261.61.32.0
20271.61.32.0
20281.71.32.0
20291.71.32.1
20301.71.32.1

Where the Ash-throated Flycatcher Is Detected

BBS routes recording Ash-throated Flycatcher, sized by most recent count.

Ash-throated Flycatcher Population Trend by State

Ash-throated Flycatcher population trend by state.
TrendPercent 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 →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
Arizona+86%197088
California+46%1970219
Colorado+900%197261
Idaho-86%19814
Kansasinsufficient datan/a2
Nevada+125%197026
New Mexico+205%197086
Oklahoma+296%198016
Oregon+46%197050
Texas+128%1969161
Utah+880%197375
Washingtoninsufficient datan/a3
Wyoming-95%197811

Ash-throated Flycatcher Population Trend by Region

Bird Conservation Regions are the ecological unit for trends.

Ash-throated Flycatcher population trend by Bird Conservation Region.
TrendPercent 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 →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
Northern Pacific Rainforest-39%197035
Great Basin+90%197093
Northern Rockies+342%197528
Sierra Nevada-73%197019
Southern Rockies / Colorado Plateau+86%1970159
Shortgrass Prairie+43%196963
Central Mixed Grass Prairie12×196935
Edwards Plateau+597%197119
Oaks and Prairies+430%197125
Coastal California+88%1970117
Sonoran and Mojave Deserts+67%197080
Sierra Madre Occidental+34%197036
Chihuahuan Desert+48%196957
Tamaulipan Brushlands+152%196927
Gulf Coastal Prairie+67%19969

Ash-throated Flycatcher Conservation Status

Our route-weighted index shows it up about 327% since 1969. Aerial insectivores have fallen sharply across the continent, a decline widely linked to dwindling insect prey.

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14. Trend is a route-weighted relative-abundance index, not an absolute population.