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

American Bittern Population Trend in Nevada

All statesWetland birds

American Bittern in Nevada has surged: up 100% on the route-weighted index since 1998.

+100%Since 1998TrendPercent 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 →
7Routes 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 →
21YearsYears 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 NevadaNotable 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 Nevada: up 100% on the route-weighted index since 1998.

American Bittern Population Forecast in Nevada

If the recent trend holds, American Bittern in Nevada is projected to fall about 43% by 2023 — from 0.24 in 2018 to a central estimate of 0.14 (95% range 0.00–0.29). A 5-year backtest shows a typical error of ±143.4%, with 100% of held-out values landing inside the 95% band.

-43%Change by 2023TrendPercent 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 →
0.14Projected 2023 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.2995% 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 →
±143.4%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, American Bittern in Nevada is projected to fall about 43% by 2023 — from 0.24 in 2018 to a central estimate of 0.14 (95% range 0.00–0.29). A 5-year backtest shows a typical error of ±143.4%, with 100% of held-out values landing inside the 95% band.19952023
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 →
20190.140.000.28
20200.140.000.29
20210.140.000.29
20220.140.000.29
20230.140.000.29

American Bittern Survey Routes in Nevada

Routes recording American Bittern in Nevada.
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 →
Virgin Creek520181995
Ash Meadows220181998
Eureka220001999
Gardnerville220061997
Ruby Valley 2120162007
Fallon120051999
Gardnerville 2120182018

American Bittern Population Trend in Other States

alaskacaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaslouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanew-hampshirenew-jerseynew-mexiconew-yorknorth-dakotaohiooklahomaoregonpennsylvaniasouth-carolinasouth-dakotatexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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