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Species · Utah · BBS 2025 Release · 1966–2024

Clark's Grebe Population Trend in Utah

All statesWetland birds

Clark's Grebe in Utah has surged: up 818% on the route-weighted index since 1992.

+818%Since 1992TrendPercent 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 →
9Routes 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 →
30YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Clark's Grebe 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 →

Clark's Grebe has surged in Utah: up 818% on the route-weighted index since 1992.

Clark's Grebe Population Forecast in Utah

If the recent trend holds, Clark's Grebe in Utah is projected to rise about 535% by 2029 — from 0.07 in 2024 to a central estimate of 0.43 (95% range 0.00–1.0). A 5-year backtest shows a typical error of ±474.9%, with 100% of held-out values landing inside the 95% band.

+535%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 →
0.43Projected 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 →
0.00–1.095% 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 →
±474.9%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, Clark's Grebe in Utah is projected to rise about 535% by 2029 — from 0.07 in 2024 to a central estimate of 0.43 (95% range 0.00–1.0). A 5-year backtest shows a typical error of ±474.9%, with 100% of held-out values landing inside the 95% band.19862029
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 →
20250.410.001.0
20260.410.001.0
20270.420.001.0
20280.430.001.0
20290.430.001.0

Clark's Grebe Survey Routes in Utah

Routes recording Clark's Grebe 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 →
Bear River1920231992
Ferron520162007
Kamas420242019
Neponset Res220161997
Goshen220121998
Saleratus Cr120112011
E. Bear Lake120011999
Lynn120211986
Callao120132011

Clark's Grebe Population Trend in Other States

arizonacaliforniacoloradoidahomontananebraskanevadanorth-dakotaoregonsouth-dakotawyoming

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