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

Common Merganser Population Trend in Minnesota

All statesWaterfowl

Common Merganser in Minnesota has edged down: down 16% on the route-weighted index since 1983.

-16%Since 1983TrendPercent 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 →
21Routes 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 →
32YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Common Merganser 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 →

No notable trend signals for Common Merganser in Minnesota. See the full index history below.

Common Merganser Population Forecast in Minnesota

If the recent trend holds, Common Merganser in Minnesota is projected to stay roughly flat through 2029, near 0.05 (95% range 0.00–0.12). A 5-year backtest shows a typical error of ±61.9%, with 60% 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 →
0.05Projected 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 →
0.00–0.1295% 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 →
±61.9%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, Common Merganser in Minnesota is projected to stay roughly flat through 2029, near 0.05 (95% range 0.00–0.12). A 5-year backtest shows a typical error of ±61.9%, with 60% of held-out values landing inside the 95% band.19722029
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 →
20250.050.000.11
20260.050.000.11
20270.050.000.11
20280.050.000.11
20290.050.000.12

Common Merganser Survey Routes in Minnesota

Routes recording Common Merganser 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 →
Wigwam Bay620182013
Cohasset320211991
Babbitt320222022
Oklee219921992
Wylie219831983
Cass Lake120072007
Mille Lacs120132009
Hovland120221994
Lockport120061972
Sawbill Lndg120141992
Hart Lake120011991
Crane Lake120241987
Waskish120072002
Brook Park120172017
Mahtowa119971997
Sawbill Camp120231994
Jordan120022002
Bigfork119991999
Blackduck120182017
Glendale120242004
Red Lake119961996

Common Merganser Population Trend in Other States

alaskaarizonacaliforniacoloradoconnecticutidahomainemarylandmassachusettsmichiganmontananevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-dakotaohiooregonpennsylvaniasouth-dakotautahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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