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

Marsh Wren Population Trend in Louisiana

All statesForest birds

Marsh Wren in Louisiana has edged down: down 15% on the route-weighted index since 1978.

-15%Since 1978TrendPercent 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 →
41YearsYears 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 LouisianaNotable 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 Louisiana. See the full index history below.

Marsh Wren Population Forecast in Louisiana

If the recent trend holds, Marsh Wren in Louisiana is projected to stay roughly flat through 2028, near 0.51 (95% range 0.00–1.4). A 5-year backtest shows a typical error of ±671.5%, 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 →
0.51Projected 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 →
0.00–1.495% 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 →
±671.5%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 Louisiana is projected to stay roughly flat through 2028, near 0.51 (95% range 0.00–1.4). A 5-year backtest shows a typical error of ±671.5%, with 100% of held-out values landing inside the 95% band.19712028
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 →
20240.520.001.4
20250.510.001.4
20260.510.001.4
20270.510.001.4
20280.510.001.4

Marsh Wren Survey Routes in Louisiana

Routes recording Marsh Wren in Louisiana.
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 →
Sabine Nwr 21620172009
Sabine Nwr1120081989
Forked Island1020192008
Ltl Chenier 2820112010
Gran Chenier619711971
Forked Island 2320112011
Freetown119781978
Morgan City119751975
Creole119711971
Ltl Chenier120231986
Hackberry120061978
Glencoe120111999

Marsh Wren Population Trend in Other States

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

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