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

American Dipper Population Trend in Utah

All statesGeneralists

American Dipper in Utah has collapsed: down 94% on the route-weighted index since 1977.

-94%Since 1977TrendPercent 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 →
14Routes 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 →
37YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable American Dipper 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 declinecomputed 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 →

American Dipper has collapsed in Utah: down 94% on the route-weighted index since 1977.

American Dipper Population Forecast in Utah

If the recent trend holds, American Dipper in Utah is projected to stay roughly flat through 2028, near 0.00 (95% range 0.00–0.31). A 5-year backtest shows a typical error of ±511.1%, with 100% of held-out values landing inside the 95% band.

n/aChange by 2028TrendPercent 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 →
0.00Projected 2028 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.3195% 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 →
±511.1%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, American Dipper in Utah is projected to stay roughly flat through 2028, near 0.00 (95% range 0.00–0.31). A 5-year backtest shows a typical error of ±511.1%, with 100% of held-out values landing inside the 95% band.19682028
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 →
20240.000.000.31
20250.000.000.31
20260.000.000.31
20270.000.000.31
20280.000.000.31

American Dipper Survey Routes in Utah

Routes recording American Dipper 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 →
Ant Flat-Ogden Can220182001
Kamas219991999
Moon Lake 2120172017
Hyrum119791977
Lost Cr. Res120151995
Altonah120151995
Logan Canyon120181997
Hardware Ranch120181994
Heber Mtn.120082008
Beaver120231979
Navajo Lake120121968
Boulder119921969
Ferron120132013
Main Canyon120151991

American Dipper Population Trend in Other States

alaskacaliforniacoloradoidahomontananevadanew-mexicooregonsouth-dakotawashingtonwyoming

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