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Species · Utah · BBS 2026 Release · 1966–2025

Dusky Flycatcher Population Trend in Utah

All statesAerial insectivores

Dusky Flycatcher in Utah has surged: up 218% on the route-weighted index since 1979.

+218%Since 1979TrendPercent 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 →
47YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Dusky Flycatcher 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 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 →

Dusky Flycatcher has surged in Utah: up 218% on the route-weighted index since 1979.

Dusky Flycatcher Population Forecast in Utah

If the recent trend holds, Dusky Flycatcher in Utah is projected to fall about 19% by 2030 — from 1.7 in 2025 to a central estimate of 1.4 (95% range 0.85–1.9). A 5-year backtest shows a typical error of ±41.6%, with 60% of held-out values landing inside the 95% band.

-19%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 →
1.4Projected 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 →
0.85–1.995% 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 →
±41.6%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, Dusky Flycatcher in Utah is projected to fall about 19% by 2030 — from 1.7 in 2025 to a central estimate of 1.4 (95% range 0.85–1.9). A 5-year backtest shows a typical error of ±41.6%, with 60% of held-out values landing inside the 95% band.19752030
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 →
20261.30.781.9
20271.30.801.9
20281.40.811.9
20291.40.831.9
20301.40.851.9

Dusky Flycatcher Survey Routes in Utah

Routes recording Dusky Flycatcher 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 →
Fish Lake Nf1420251992
Lost Cr. Res1220181995
La Sal1220001994
Dixie Nf1220251993
Beck 21220251990
Beck1019871986
Grizzly Rdge1020251993
Fayette1020251992
Moon Lake 2920232004
Woodruff720252007
Saleratus Cr620131995
Randolph620251992
Uintah Nf619941991
Wasatch Nf620241991
La Sal 3620252007
Neponset Res520021996
Oak City520151984
Beaver520251979
Gooseberry520251994
Soapstone420251992
M Warner Res420252006
Hanna420231997
Ferron420252000
Monticello420252025
Hyrum319791975

Dusky Flycatcher Population Trend in Other States

arizonacaliforniacoloradoidahomontananebraskanevadanew-mexicooregonsouth-dakotawashingtonwyoming

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