BirdAnalyst
Species · Nevada · BBS 2026 Release · 1966–2025

Marsh Wren Population Trend in Nevada

All statesForest birds

Marsh Wren in Nevada has edged down: down 21% on the route-weighted index since 1995.

-21%Since 1995TrendPercent 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 →
12Routes 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 →
31YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Marsh Wren 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 →

No notable trend signals for Marsh Wren in Nevada. See the full index history below.

Marsh Wren Population Forecast in Nevada

If the recent trend holds, Marsh Wren in Nevada is projected to fall about 27% by 2030 — from 0.14 in 2025 to a central estimate of 0.10 (95% range 0.00–0.53). A 5-year backtest shows a typical error of ±45.4%, with 100% of held-out values landing inside the 95% band.

-27%Change by 2030TrendPercent 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 →
0.10Projected 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.5395% 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 →
±45.4%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, Marsh Wren in Nevada is projected to fall about 27% by 2030 — from 0.14 in 2025 to a central estimate of 0.10 (95% range 0.00–0.53). A 5-year backtest shows a typical error of ±45.4%, with 100% of held-out values landing inside the 95% band.19932030
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 →
20260.150.000.57
20270.140.000.56
20280.130.000.55
20290.120.000.54
20300.100.000.53

Marsh Wren Survey Routes in Nevada

Routes recording Marsh Wren 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 →
Gardnerville420111994
Ranchogrande320081995
Virgin Creek320151995
Fallon220251996
Hiko220222010
Beatty220172013
Jarbidge120132013
Bald Mtn.120232015
Cortez120212016
Ash Meadows120191993
Meadow Vally120182018
Gardnerville 2120252025

Marsh Wren Population Trend in Other States

alabamaarizonacaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaslouisianamainemarylandmassachusettsmichiganminnesotamissourimontananebraskanew-hampshirenew-jerseynew-yorknorth-carolinanorth-dakotaohiooregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatexasutahvermontvirginiawashingtonwisconsinwyoming

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.