WhenToBird

Mergus serrator · Anatidae

When Do Red-breasted Mergansers Arrive in West Virginia?

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

Red-breasted Mergansers are winter birds in West Virginia: they arrive in mid November, peak in late March (2.1% of checklists), and most are gone by late April.

When to look

First arrivalsNov 15-21mid November
Common byNov 15-21mid November
PeakMar 22-31late March
Most gone byApr 22-30late April

Best: late March. First arrivals mid November; most are gone by late April. Peak: on about 2.1% of West Virginia checklists.

  1. Januncommon
  2. Febcommon
  3. Marpeak season
  4. Aprpeak season
  5. Mayuncommon
  6. Junnot usually seen
  7. Julnot usually seen
  8. Augnot usually seen
  9. Sepnot usually seen
  10. Octrare
  11. Novcommon
  12. Deccommon

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

0%1%2%3%Jan 1-7: 0.6% of 4227 checklistsJan 8-14: 0.6% of 3147 checklistsJan 15-21: 0.9% of 3410 checklistsJan 22-31: 0.8% of 4248 checklistsFeb 1-7: 0.6% of 3150 checklistsFeb 8-14: 0.8% of 3653 checklistsFeb 15-21: 0.8% of 5140 checklistsFeb 22-28: 1.4% of 3846 checklistsMar 1-7: 0.9% of 3901 checklistsMar 8-14: 1.3% of 3820 checklistsMar 15-21: 1.8% of 3781 checklistsMar 22-31: 1.7% of 5705 checklistsApr 1-7: 2.9% of 4529 checklistsApr 8-14: 1.8% of 4935 checklistsApr 15-21: 1.1% of 5429 checklistsApr 22-30: 0.6% of 8015 checklistsMay 1-7: 0.4% of 7421 checklistsMay 8-14: 0.3% of 6910 checklistsMay 15-21: 0.1% of 5596 checklistsMay 22-31: 0.1% of 6884 checklistsJun 1-7: 0% of 4123 checklistsJun 8-14: 0.1% of 3957 checklistsJun 15-21: 0.1% of 3863 checklistsJun 22-30: 0% of 4217 checklistsJul 1-7: 0% of 3491 checklistsJul 8-14: 0% of 3044 checklistsJul 15-21: 0% of 3095 checklistsJul 22-31: 0% of 4120 checklistsAug 1-7: 0% of 3009 checklistsAug 8-14: 0.1% of 3007 checklistsAug 15-21: 0% of 2905 checklistsAug 22-31: 0.1% of 4312 checklistsSep 1-7: 0% of 3429 checklistsSep 8-14: 0% of 3217 checklistsSep 15-21: 0% of 3285 checklistsSep 22-30: 0% of 4067 checklistsOct 1-7: 0% of 3380 checklistsOct 8-14: 0% of 3460 checklistsOct 15-21: 0.1% of 3129 checklistsOct 22-31: 0% of 3881 checklistsNov 1-7: 0.2% of 3084 checklistsNov 8-14: 0.4% of 2869 checklistsNov 15-21: 0.6% of 2484 checklistsNov 22-30: 0.7% of 3663 checklistsDec 1-7: 1.7% of 2574 checklistsDec 8-14: 0.8% of 2680 checklistsDec 15-21: 0.4% of 3792 checklistsDec 22-31: 0.4% of 4236 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 West Virginia 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 West Virginia

Best counties

Share of checklists at the peak
  1. Grant CountyBest early April · 46 checklists that week, 3,867 in all14%
  2. Taylor CountyBest the second week of December · 39 checklists that week, 2,541 in all10%
  3. Mason CountyBest the second week of April · 50 checklists that week, 2,835 in all8.6%
  4. Barbour CountyBest the second week of April · 52 checklists that week, 1,534 in all8.5%
  5. Cabell CountyBest the second week of December · 29 checklists that week, 4,032 in all7.9%
  6. Pleasants CountyBest early March · 59 checklists that week, 1,671 in all7.3%

Best spots

Share of checklists at the peak
  1. Hulls LakePreston County, best late March · 22 checklists that week, 446 in all56%
  2. Cheat Lake ParkMonongalia County, best late March · 23 checklists that week, 435 in all32%
  3. Tygart Lake State ParkTaylor County, best early April · 22 checklists that week, 259 in all16%
  4. Cow CreekPleasants County, best early January · 21 checklists that week, 357 in all13%

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

Best time of day

In West Virginia, the Red-breasted Merganser is most often listed on checklists started between 2 and 4 pm (0.7% of those checklists).

0%0.5%1%12 am: too few checklists (65) to judge1 am: too few checklists (47) to judge2 am: too few checklists (46) to judge3 am: too few checklists (49) to judge4 am: too few checklists (140) to judge5 am: too few checklists (952) to judge6 am: 0.3% of 5860 checklists7 am: 0.2% of 18233 checklists8 am: 0.4% of 24468 checklists9 am: 0.7% of 22542 checklists10 am: 0.7% of 19537 checklists11 am: 0.6% of 16362 checklists12 pm: 0.6% of 14819 checklists1 pm: 0.6% of 12772 checklists2 pm: 0.8% of 11765 checklists3 pm: 0.7% of 12579 checklists4 pm: 0.6% of 11463 checklists5 pm: 0.5% of 9409 checklists6 pm: 0.3% of 6557 checklists7 pm: 0.2% of 4256 checklists8 pm: too few checklists (1589) to judge9 pm: too few checklists (377) to judge10 pm: too few checklists (147) to judge11 pm: too few checklists (86) 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%0.6%0.9%0.8%
February0.6%0.8%0.8%1.4%
March0.9%1.3%1.8%1.7%
April2.9%1.8%1.1%0.6%
May0.4%0.3%0.1%0.1%
June0%0.1%0.1%0%
July0%0%0%0%
August0%0.1%0%0.1%
September0%0%0%0%
October0%0%0.1%0%
November0.2%0.4%0.6%0.7%
December1.7%0.8%0.4%0.4%

Neighboring states

  • Virginia: arrives mid November, in the same week than West Virginia
  • District of Columbia: arrives late December, 5 weeks later than West Virginia
  • Maryland: arrives mid November, in the same week than West Virginia
  • Ohio: arrives late October, 3 weeks earlier than West Virginia

Common questions

When do Red-breasted Mergansers arrive in West Virginia?
Red-breasted Mergansers are winter birds in West Virginia: they arrive in mid November, peak in late March (2.1% of checklists), and most are gone by late April.
When do Red-breasted Mergansers leave West Virginia?
Most Red-breasted Mergansers have left West Virginia by late April, when reports fall below half their usual rate.
When is the best time to see a Red-breasted Merganser in West Virginia?
The Red-breasted Merganser is reported most often in late March, on about 2.1% of West Virginia checklists.
Where in West Virginia are Red-breasted Mergansers seen most often?
By county, Grant County, Taylor County, and Mason County have the highest peak reporting rates for the Red-breasted Merganser (counties with at least 200 checklists).