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

Marsh Wren Population Trend in Minnesota

All statesForest birds

Marsh Wren in Minnesota has surged: up 204% on the route-weighted index since 1969.

+204%Since 1969TrendPercent 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 →
66Routes 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 →
57YearsYears 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 MinnesotaNotable 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 →

Marsh Wren has surged in Minnesota: up 204% on the route-weighted index since 1969.

Marsh Wren Population Forecast in Minnesota

If the recent trend holds, Marsh Wren in Minnesota is projected to rise about 26% by 2029 — from 1.6 in 2024 to a central estimate of 2.1 (95% range 1.1–3.0). A 5-year backtest shows a typical error of ±16.7%, with 100% of held-out values landing inside the 95% band.

+26%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 →
2.1Projected 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 →
1.1–3.095% 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 →
±16.7%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 Minnesota is projected to rise about 26% by 2029 — from 1.6 in 2024 to a central estimate of 2.1 (95% range 1.1–3.0). A 5-year backtest shows a typical error of ±16.7%, with 100% of held-out values landing inside the 95% band.19672029
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 →
20252.01.02.9
20262.01.02.9
20272.01.13.0
20282.01.13.0
20292.11.13.0

Marsh Wren Survey Routes in Minnesota

Routes recording Marsh Wren in Minnesota.
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 →
Sherburne Nr2520241990
Big Stone2020121995
Little Fork1219901990
Cohasset1119901990
Tracy1120242005
Chokio1020241969
Ashby920211997
Maynard720151986
Chokio North620242011
Osseo520041967
Knapp520241967
Backus520241970
Lake Bronson520111998
Fairmont520232003
Franklin520242005
New London520241994
Minnetonka420221969
Appleton420241980
Worthington420242005
Beltrami320061976
Glenwood320181993
Chandler220232022
Lakeville219991976
Evergreen220181967
Glyndon220241980

Marsh Wren Population Trend in Other States

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

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