WhenToBird

Mergus serrator · Anatidae

When Do Red-breasted Mergansers Arrive in Minnesota?

Adult male Red-breasted Merganser
Photo: Peter Chen 2.0, CC BY 4.0 via iNaturalist

Red-breasted Mergansers arrive in Minnesota in the second week of March, peak in the second week of April (6.0% of checklists), and most are gone by late May.

When to look

First arrivalsMar 8-14the second week of March
Common byMar 8-14the second week of March
PeakApr 8-14the second week of April
Most gone byMay 22-31late May

Best: the second week of April. First arrivals the second week of March; most are gone by late May. Peak: on about 6.0% of Minnesota checklists.

  1. Januncommon
  2. Febrare
  3. Marcommon
  4. Aprpeak season
  5. Maycommon
  6. Junrare
  7. Julnot usually seen
  8. Augnot usually seen
  9. Seprare
  10. Octuncommon
  11. Novuncommon
  12. Decuncommon

Darker months: more checklists report it. Outlined: peak month.

0%2%4%6%8%Jan 1-7: 0.6% of 20628 checklistsJan 8-14: 1.0% of 14594 checklistsJan 15-21: 1.0% of 14238 checklistsJan 22-31: 0.9% of 20725 checklistsFeb 1-7: 0.8% of 14484 checklistsFeb 8-14: 0.6% of 15988 checklistsFeb 15-21: 0.5% of 20718 checklistsFeb 22-28: 0.4% of 15754 checklistsMar 1-7: 0.5% of 16125 checklistsMar 8-14: 0.8% of 19035 checklistsMar 15-21: 1.5% of 19586 checklistsMar 22-31: 3.4% of 30192 checklistsApr 1-7: 5.0% of 24262 checklistsApr 8-14: 6.4% of 30223 checklistsApr 15-21: 6.5% of 29085 checklistsApr 22-30: 4.8% of 43574 checklistsMay 1-7: 2.4% of 39300 checklistsMay 8-14: 1.1% of 45927 checklistsMay 15-21: 1.0% of 36632 checklistsMay 22-31: 1.0% of 43809 checklistsJun 1-7: 0.4% of 23418 checklistsJun 8-14: 0.2% of 20450 checklistsJun 15-21: 0.2% of 19470 checklistsJun 22-30: 0.2% of 23418 checklistsJul 1-7: 0.2% of 19104 checklistsJul 8-14: 0.2% of 16927 checklistsJul 15-21: 0.2% of 15635 checklistsJul 22-31: 0.2% of 22073 checklistsAug 1-7: 0.2% of 16255 checklistsAug 8-14: 0.2% of 16840 checklistsAug 15-21: 0.2% of 17475 checklistsAug 22-31: 0.2% of 26545 checklistsSep 1-7: 0.2% of 20750 checklistsSep 8-14: 0.3% of 18494 checklistsSep 15-21: 0.4% of 18215 checklistsSep 22-30: 0.4% of 24463 checklistsOct 1-7: 0.4% of 18252 checklistsOct 8-14: 0.4% of 19527 checklistsOct 15-21: 0.9% of 17098 checklistsOct 22-31: 2.0% of 24570 checklistsNov 1-7: 2.5% of 16744 checklistsNov 8-14: 2.4% of 13483 checklistsNov 15-21: 1.8% of 12525 checklistsNov 22-30: 2.0% of 17023 checklistsDec 1-7: 1.5% of 11645 checklistsDec 8-14: 1.1% of 11567 checklistsDec 15-21: 0.6% of 13343 checklistsDec 22-31: 0.5% of 19759 checklistsJanFebMarAprMayJunJulAugSepOctNovDec
Share of complete checklists reporting it, by week (4 per month). Grey bars: fewer than 10 checklists, not counted.

Frequency is the share of complete checklists in Minnesota that listed the bird, 2016–2025. It is not a head count, and it follows where and when people go birding. How to read it.

JanFebMarAprMayJunJulAugSepOctNovDec
today
Second week of November

Each county is shaded by the share of complete checklists there that listed the bird, blended with the weeks either side. Darker is more often. It follows where people watch birds, not how many birds there are. How to read it.

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Where in Minnesota

Best counties

Share of checklists at the peak
  1. Freeborn CountyBest early April · 38 checklists that week, 2,409 in all24%
  2. Dodge CountyBest the second week of April · 25 checklists that week, 1,179 in all20%
  3. Beltrami CountyBest late April · 261 checklists that week, 6,476 in all16%
  4. Faribault CountyBest the second week of April · 34 checklists that week, 1,448 in all14%
  5. Lincoln CountyBest the second week of April · 85 checklists that week, 1,063 in all14%
  6. Waseca CountyBest early April · 17 checklists that week, 1,630 in all13%

Best spots

Share of checklists at the peak
  1. Lake Harriet (southwest)Hennepin County, best the second week of April · 205 checklists that week, 2,817 in all88%
  2. Lake Harriet (west)Hennepin County, best the second week of April · 33 checklists that week, 307 in all80%
  3. Spring LakeScott County, best early April · 27 checklists that week, 384 in all77%
  4. Minnesota Point (Park Point)St. Louis County, best the second week of April · 23 checklists that week, 336 in all75%
  5. Bde Maka SkaHennepin County, best the second week of April · 116 checklists that week, 1,773 in all72%
  6. Paul Bunyan Park (Bemidji)Beltrami County, best mid April · 21 checklists that week, 131 in all67%

Busy spots report more of everything; compare the checklist counts before you drive anywhere.

Best time of day

In Minnesota, the Red-breasted Merganser is most often listed on checklists started between 12 and 2 pm (1.7% of those checklists).

0%0.5%1%1.5%2%12 am: too few checklists (349) to judge1 am: too few checklists (331) to judge2 am: too few checklists (286) to judge3 am: too few checklists (364) to judge4 am: too few checklists (863) to judge5 am: too few checklists (7598) to judge6 am: 1.5% of 35775 checklists7 am: 1.2% of 90565 checklists8 am: 1.2% of 110612 checklists9 am: 1.4% of 106128 checklists10 am: 1.4% of 96131 checklists11 am: 1.5% of 83750 checklists12 pm: 1.8% of 76254 checklists1 pm: 1.7% of 73480 checklists2 pm: 1.7% of 73703 checklists3 pm: 1.8% of 75249 checklists4 pm: 1.6% of 68810 checklists5 pm: 1.7% of 51899 checklists6 pm: 1.7% of 38524 checklists7 pm: 1.2% of 25120 checklists8 pm: too few checklists (10568) to judge9 pm: too few checklists (2420) to judge10 pm: too few checklists (748) to judge11 pm: too few checklists (420) to judge12a3a6a9a12p3p6p9p
Share of checklists started in each local hour that reported it. It reflects when people go birding as well as when birds are active. Grey hours have too few checklists (under 2% of the state’s, or under 200) to judge.
Week-by-week table
MonthDays 1-78-1415-2122-end
January0.6%1.0%1.0%0.9%
February0.8%0.6%0.5%0.4%
March0.5%0.8%1.5%3.4%
April5.0%6.4%6.5%4.8%
May2.4%1.1%1.0%1.0%
June0.4%0.2%0.2%0.2%
July0.2%0.2%0.2%0.2%
August0.2%0.2%0.2%0.2%
September0.2%0.3%0.4%0.4%
October0.4%0.4%0.9%2.0%
November2.5%2.4%1.8%2.0%
December1.5%1.1%0.6%0.5%

Neighboring states

  • Iowa: arrives late February, 2 weeks earlier than Minnesota
  • Wisconsin: arrives mid October, 19 weeks earlier than Minnesota
  • South Dakota: arrives the second week of November, 16 weeks earlier than Minnesota
  • North Dakota: arrives mid October, 19 weeks earlier than Minnesota

Common questions

When do Red-breasted Mergansers arrive in Minnesota?
Red-breasted Mergansers arrive in Minnesota in the second week of March, peak in the second week of April (6.0% of checklists), and most are gone by late May.
When do Red-breasted Mergansers leave Minnesota?
Most Red-breasted Mergansers have left Minnesota by late May, when reports fall below half their usual rate.
When is the best time to see a Red-breasted Merganser in Minnesota?
The Red-breasted Merganser is reported most often in the second week of April, on about 6.0% of Minnesota checklists.
Where in Minnesota are Red-breasted Mergansers seen most often?
By county, Freeborn County, Dodge County, and Beltrami County have the highest peak reporting rates for the Red-breasted Merganser (counties with at least 200 checklists).