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

Hermit Thrush Population Trend in Utah

All statesForest birds

Hermit Thrush in Utah has increased: up 29% on the route-weighted index since 1970.

+29%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 →
43Routes 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 →
54YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Hermit Thrush 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 →

No notable trend signals for Hermit Thrush in Utah. See the full index history below.

Hermit Thrush Population Forecast in Utah

If the recent trend holds, Hermit Thrush in Utah is projected to stay roughly flat through 2029, near 4.5 (95% range 1.9–7.1). A 5-year backtest shows a typical error of ±50.3%, with 80% of held-out values landing inside the 95% band.

+2%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 →
4.5Projected 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 →
1.9–7.195% 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 →
±50.3%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, Hermit Thrush in Utah is projected to stay roughly flat through 2029, near 4.5 (95% range 1.9–7.1). A 5-year backtest shows a typical error of ±50.3%, 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 →
20254.31.76.9
20264.41.86.9
20274.41.87.0
20284.51.97.0
20294.51.97.1

Hermit Thrush Survey Routes in Utah

Routes recording Hermit Thrush 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 →
Grizzly Rdge4920241987
Navajo Lake4820241970
Fish Lake Nf2520241992
La Sal2420001993
Heber Mtn.2420241996
Red Spur Mtn.2320231997
La Sal 32320242007
Wasatch Nf2120241988
La Sal 22020062003
Soapstone1920241992
Bryce Canyon1620241990
Beck1519871968
Uintah Nf1419941988
Gooseberry1220241994
Beck 21120181990
Logan Canyon1020191997
Woodruff1020242002
Ferron1020222000
Monticello820241998
Moon Lake720031994
Skyline Driv720161986
Book Ridge620062003
Cleveland620001992
Hyrum519771975
Richfield520191994

Hermit Thrush Population Trend in Other States

alaskaarizonacaliforniacoloradoconnecticutidahomainemarylandmassachusettsmichiganminnesotamontananevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinaohiooregonpennsylvaniarhode-islandsouth-dakotatennesseetexasvermontvirginiawashingtonwest-virginiawisconsinwyoming

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