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

American Bittern Population Trend in Utah

All statesWetland birds

American Bittern in Utah has surged: up 376% on the route-weighted index since 1996.

+376%Since 1996TrendPercent 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 →
6Routes 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 →
26YearsYears 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 Bittern 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 →

American Bittern has surged in Utah: up 376% on the route-weighted index since 1996.

American Bittern Population Forecast in Utah

If the recent trend holds, American Bittern in Utah is projected to fall about 32% by 2029 — from 0.14 in 2024 to a central estimate of 0.09 (95% range 0.01–0.18). A 5-year backtest shows a typical error of ±80.8%, with 100% of held-out values landing inside the 95% band.

-32%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 →
0.09Projected 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 →
0.01–0.1895% 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 →
±80.8%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 Bittern in Utah is projected to fall about 32% by 2029 — from 0.14 in 2024 to a central estimate of 0.09 (95% range 0.01–0.18). A 5-year backtest shows a typical error of ±80.8%, with 100% of held-out values landing inside the 95% band.19942029
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 →
20250.090.000.17
20260.090.000.17
20270.090.010.17
20280.090.010.17
20290.090.010.18

American Bittern Survey Routes in Utah

Routes recording American Bittern 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 →
Jensen320242009
Promontory220062006
Randolph220241994
Callao220242003
Salt Springs120241997
Bear River120082006

American Bittern Population Trend in Other States

alaskacaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaslouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-dakotaohiooklahomaoregonpennsylvaniasouth-carolinasouth-dakotatexasvermontvirginiawashingtonwest-virginiawisconsinwyoming

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