BirdAnalyst
Species · BCR 17 · BBS 2025 Release · 1966–2024

Marsh Wren In Badlands and Prairies

All regionsBadlands and PrairiesForest birds

Marsh Wren in Badlands and Prairies has risen sharply: up 59% on the route-weighted index since 1970.

+59%Since 1970TrendPercent 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 →
24Routes In RegionSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
35YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable SignalsNotable 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 risen sharply in Badlands and Prairies: up 59% on the route-weighted index since 1970.

Marsh Wren In Badlands and Prairies Population Forecast

If the recent trend holds, Marsh Wren in Badlands and Prairies is projected to stay roughly flat through 2029, near 0.06 (95% range 0.00–0.14). A 5-year backtest shows a typical error of ±155.5%, with 80% of held-out values landing inside the 95% band.

n/aChange 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 →
0.06Projected 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 →
0.00–0.1495% 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 →
±155.5%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 Badlands and Prairies is projected to stay roughly flat through 2029, near 0.06 (95% range 0.00–0.14). A 5-year backtest shows a typical error of ±155.5%, with 80% of held-out values landing inside the 95% band.19682029
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 →
20250.060.000.14
20260.060.000.14
20270.060.000.14
20280.060.000.14
20290.060.000.14

Routes In Badlands and Prairies

Routes recording Marsh Wren in Badlands and Prairies.
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 →
Dunn CenterNORTH-DAKOTA52016
Ft ThompsonSOUTH-DAKOTA42002
LacreekSOUTH-DAKOTA32018
S. PioneerSOUTH-DAKOTA31995
Two DotMONTANA22018
BowmanNORTH-DAKOTA22014
ZapNORTH-DAKOTA22024
Cedar CreekNORTH-DAKOTA22011
HighwoodMONTANA12008
BrusettMONTANA12017
BrandenbergMONTANA11974
Miles CityMONTANA12019
Ft YatesNORTH-DAKOTA12003
DickinsonNORTH-DAKOTA12021
GorhamNORTH-DAKOTA12018
GolvaNORTH-DAKOTA12008
BentleyNORTH-DAKOTA12001
Glen UllinNORTH-DAKOTA12022
SolenNORTH-DAKOTA12013
CarsonNORTH-DAKOTA12018
ChamberlainSOUTH-DAKOTA12005
ArdmoreSOUTH-DAKOTA12015
Long DrawSOUTH-DAKOTA11995
Harland FlatWYOMING12024

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