BirdAnalyst
Species · Utah · BBS 2026 Release · 1966–2025

Rock Wren Population Trend in Utah

All statesForest birds

Rock Wren in Utah has surged: up 213% on the route-weighted index since 1970.

+213%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 →
106Routes 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 →
52YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Rock Wren 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 →

Rock Wren has surged in Utah: up 213% on the route-weighted index since 1970.

Rock Wren Population Forecast in Utah

If the recent trend holds, Rock Wren in Utah is projected to rise about 50% by 2030 — from 3.6 in 2025 to a central estimate of 5.4 (95% range 2.7–8.0). A 5-year backtest shows a typical error of ±50.4%, with 80% of held-out values landing inside the 95% band.

+50%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 →
5.4Projected 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 →
2.7–8.095% 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 →
±50.4%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, Rock Wren in Utah is projected to rise about 50% by 2030 — from 3.6 in 2025 to a central estimate of 5.4 (95% range 2.7–8.0). A 5-year backtest shows a typical error of ±50.4%, with 80% of held-out values landing inside the 95% band.19682030
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 →
20265.12.47.8
20275.22.57.8
20285.22.67.9
20295.32.68.0
20305.42.78.0

Rock Wren Survey Routes in Utah

Routes recording Rock Wren 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 →
Bonanza8020151992
Salt Springs2820251986
Bicknell2720251997
Gold Hill1820251991
Crawford Mts1820232002
Desert View1720251987
Fayette1720251992
Hatch1620251994
Lake Powell1520071993
Notom1320251987
Castleton1219851969
Willow Creek1120241986
Moab1120251986
Leamington1020171992
Hanna1020241997
Peplin Mountain920251999
Moon Lake 2920232004
Jensen720251992
Hill Creek719951994
Vernal720182003
Pine Creek720231997
Westwater620251997
Arches Np620101989
Wendover520101987
Gilson Butte520041993

Rock Wren Population Trend in Other States

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