WhenToBird

Mergus serrator · Anatidae

When Do Red-breasted Mergansers Arrive in Oklahoma?

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

Red-breasted Mergansers are winter birds in Oklahoma: they arrive in early November, peak in the second week of January (4.9% of checklists), and most are gone by late March.

When to look

First arrivalsNov 1-7early November
Common byNov 1-7early November
PeakJan 8-14the second week of January
Most gone byMar 22-31late March

Best: the second week of January. First arrivals early November; most are gone by late March. Peak: on about 4.9% of Oklahoma checklists.

  1. Janpeak season
  2. Febcommon
  3. Marcommon
  4. Apruncommon
  5. Mayrare
  6. Junnot usually seen
  7. Julnot usually seen
  8. Augnot usually seen
  9. Sepnot usually seen
  10. Octuncommon
  11. Novpeak season
  12. Decpeak season

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

0%2%4%6%Jan 1-7: 4.9% of 6087 checklistsJan 8-14: 5.2% of 4350 checklistsJan 15-21: 4.5% of 4381 checklistsJan 22-31: 3.6% of 6165 checklistsFeb 1-7: 3.0% of 4259 checklistsFeb 8-14: 2.7% of 4589 checklistsFeb 15-21: 1.6% of 7001 checklistsFeb 22-28: 2.9% of 4482 checklistsMar 1-7: 2.2% of 4724 checklistsMar 8-14: 2.5% of 4571 checklistsMar 15-21: 2.1% of 4393 checklistsMar 22-31: 1.5% of 7544 checklistsApr 1-7: 2.0% of 5967 checklistsApr 8-14: 0.7% of 6543 checklistsApr 15-21: 0.5% of 7366 checklistsApr 22-30: 0.3% of 10618 checklistsMay 1-7: 0.2% of 8835 checklistsMay 8-14: 0.1% of 8247 checklistsMay 15-21: 0.1% of 6081 checklistsMay 22-31: 0.1% of 7283 checklistsJun 1-7: 0.1% of 4256 checklistsJun 8-14: 0.2% of 3774 checklistsJun 15-21: 0.1% of 3541 checklistsJun 22-30: 0.1% of 4159 checklistsJul 1-7: 0% of 3209 checklistsJul 8-14: 0.1% of 2916 checklistsJul 15-21: 0.1% of 2861 checklistsJul 22-31: 0% of 4146 checklistsAug 1-7: 0.1% of 3043 checklistsAug 8-14: 0% of 2839 checklistsAug 15-21: 0% of 3014 checklistsAug 22-31: 0% of 4759 checklistsSep 1-7: 0% of 3861 checklistsSep 8-14: 0% of 3748 checklistsSep 15-21: 0% of 3569 checklistsSep 22-30: 0% of 4830 checklistsOct 1-7: 0% of 3809 checklistsOct 8-14: 0% of 4142 checklistsOct 15-21: 0% of 3705 checklistsOct 22-31: 0.4% of 4738 checklistsNov 1-7: 2.5% of 3823 checklistsNov 8-14: 4.0% of 3849 checklistsNov 15-21: 4.6% of 3722 checklistsNov 22-30: 4.7% of 4795 checklistsDec 1-7: 3.9% of 3324 checklistsDec 8-14: 4.0% of 3574 checklistsDec 15-21: 3.3% of 3884 checklistsDec 22-31: 3.1% of 5774 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 Oklahoma 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 Oklahoma

Best counties

Share of checklists at the peak
  1. Noble CountyBest early December · 35 checklists that week, 1,320 in all31%
  2. Canadian CountyBest the second week of January · 110 checklists that week, 4,307 in all22%
  3. Blaine CountyBest late November · 16 checklists that week, 732 in all16%
  4. Pawnee CountyBest late January · 33 checklists that week, 948 in all14%
  5. Kay CountyBest early December · 20 checklists that week, 897 in all13%
  6. Oklahoma CountyBest the second week of January · 944 checklists that week, 38,139 in all12%

Best spots

Share of checklists at the peak
  1. Lynn Lane ReservoirTulsa County, best early January · 51 checklists that week, 372 in all81%
  2. Lake YaholaTulsa County, best mid November · 33 checklists that week, 1,291 in all75%
  3. Lake Hefner (north)Oklahoma County, best late January · 23 checklists that week, 276 in all70%
  4. Lake Hefner (Ski Island Lake)Oklahoma County, best the second week of January · 37 checklists that week, 428 in all58%
  5. Lake Hefner (northeast)Oklahoma County, best early March · 20 checklists that week, 807 in all46%

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

Best time of day

In Oklahoma, the Red-breasted Merganser is most often listed on checklists started between 2 and 4 pm (2.2% of those checklists).

0%1%2%3%12 am: too few checklists (91) to judge1 am: too few checklists (65) to judge2 am: too few checklists (73) to judge3 am: too few checklists (73) to judge4 am: too few checklists (100) to judge5 am: too few checklists (647) to judge6 am: 0.3% of 8353 checklists7 am: 1.2% of 24509 checklists8 am: 1.5% of 27848 checklists9 am: 1.5% of 25316 checklists10 am: 1.6% of 21161 checklists11 am: 1.7% of 18730 checklists12 pm: 1.5% of 16097 checklists1 pm: 1.9% of 14028 checklists2 pm: 2.1% of 13599 checklists3 pm: 2.4% of 14228 checklists4 pm: 1.9% of 14597 checklists5 pm: 1.2% of 12125 checklists6 pm: 0.4% of 9337 checklists7 pm: 0.2% of 6944 checklists8 pm: too few checklists (2403) to judge9 pm: too few checklists (459) to judge10 pm: too few checklists (226) to judge11 pm: too few checklists (141) 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
January4.9%5.2%4.5%3.6%
February3.0%2.7%1.6%2.9%
March2.2%2.5%2.1%1.5%
April2.0%0.7%0.5%0.3%
May0.2%0.1%0.1%0.1%
June0.1%0.2%0.1%0.1%
July0%0.1%0.1%0%
August0.1%0%0%0%
September0%0%0%0%
October0%0%0%0.4%
November2.5%4.0%4.6%4.7%
December3.9%4.0%3.3%3.1%

Neighboring states

  • Kansas: arrives early November, in the same week than Oklahoma
  • Arkansas: arrives early November, in the same week than Oklahoma
  • Missouri: arrives early November, in the same week than Oklahoma
  • Nebraska: arrives early November, in the same week than Oklahoma

Common questions

When do Red-breasted Mergansers arrive in Oklahoma?
Red-breasted Mergansers are winter birds in Oklahoma: they arrive in early November, peak in the second week of January (4.9% of checklists), and most are gone by late March.
When do Red-breasted Mergansers leave Oklahoma?
Most Red-breasted Mergansers have left Oklahoma by late March, when reports fall below half their usual rate. Stragglers are still reported until the second week of April.
When is the best time to see a Red-breasted Merganser in Oklahoma?
The Red-breasted Merganser is reported most often in the second week of January, on about 4.9% of Oklahoma checklists.
Where in Oklahoma are Red-breasted Mergansers seen most often?
By county, Noble County, Canadian County, and Blaine County have the highest peak reporting rates for the Red-breasted Merganser (counties with at least 200 checklists).