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Species · Utah · BBS 2025 Release · 1966–2024

Rock Wren Population Trend in Utah

All statesForest birds

Rock Wren in Utah has surged: up 232% on the route-weighted index since 1970.

+232%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 →
51YearsYears 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 232% 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 35% by 2029 — from 4.0 in 2024 to a central estimate of 5.4 (95% range 2.8–8.1). A 5-year backtest shows a typical error of ±39.7%, with 80% of held-out values landing inside the 95% band.

+35%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 →
5.4Projected 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 →
2.8–8.195% 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 →
±39.7%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 35% by 2029 — from 4.0 in 2024 to a central estimate of 5.4 (95% range 2.8–8.1). A 5-year backtest shows a typical error of ±39.7%, 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 →
20255.22.57.8
20265.22.67.9
20275.32.78.0
20285.42.78.0
20295.42.88.1

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
Desert View3320241987
Shivwitz2120241993
Hite1820231986
Crawford Mts1820232002
Cleveland1620241992
Notom1520241987
Lake Powell1520071993
Peplin Mountain1420241999
Canyon Rims1420241998
Castleton1219851969
Glen Canyon1220241993
Willow Creek1120241986
Leamington1020171992
Hanna1020241997
Promontory920241969
Randolph920241992
Castle Dale920241993
Moon Lake 2920232004
Jensen820241992
Fayette820211992
Hill Creek719951994
Goose Creek Mtn.720232002
Vernal720182003
Pine Creek720231997

Rock Wren Population Trend in Other States

arizonacaliforniacoloradoidahokansasmontananebraskanevadanew-mexiconorth-dakotaoklahomaoregonsouth-dakotatexaswashingtonwyoming

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