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Species · Minnesota · BBS 2025 Release · 1966–2024

Northern Waterthrush Population Trend in Minnesota

All statesForest birds

Northern Waterthrush in Minnesota has surged: up 378% on the route-weighted index since 1969.

+378%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 →
36Routes 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 Northern Waterthrush 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 →

Northern Waterthrush has surged in Minnesota: up 378% on the route-weighted index since 1969.

Northern Waterthrush Population Forecast in Minnesota

If the recent trend holds, Northern Waterthrush in Minnesota is projected to fall about 18% by 2029 — from 0.64 in 2024 to a central estimate of 0.52 (95% range 0.22–0.82). A 5-year backtest shows a typical error of ±28.9%, with 100% of held-out values landing inside the 95% band.

-18%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 →
0.52Projected 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 →
0.22–0.8295% 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 →
±28.9%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, Northern Waterthrush in Minnesota is projected to fall about 18% by 2029 — from 0.64 in 2024 to a central estimate of 0.52 (95% range 0.22–0.82). A 5-year backtest shows a typical error of ±28.9%, 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 →
20250.500.200.80
20260.500.200.80
20270.510.210.81
20280.520.210.81
20290.520.220.82

Northern Waterthrush Survey Routes in Minnesota

Routes recording Northern Waterthrush 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 →
Sawbill Camp1020241993
Waskish820241982
Sherry Lake720221972
Floodwood520241970
Wigwam Bay320232013
Hovland319921974
Babbitt320141996
Bigfork320232010
Blackduck320222014
Glendale320242004
Red Lake320231994
Tamarac Nwr220102004
Cromwell220241985
Lockport220231967
Sawbill Lndg220241975
Hart Lake220241967
Crane Lake220231971
Erie219891989
Cass Lake120161980
Nebish120231982
Mille Lacs120241995
Pine River120012001
Island Lake119751974
Cohasset120111985
Bemidji119801979

Northern Waterthrush Population Trend in Other States

alaskaconnecticutidahomainemarylandmassachusettsmichiganmontananew-hampshirenew-jerseynew-yorknorth-carolinanorth-dakotaohiopennsylvaniarhode-islandvermontvirginiawashingtonwest-virginiawisconsinwyoming

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