WhenToBird

Lophodytes cucullatus · Anatidae

When Do Hooded Mergansers Arrive in District of Columbia?

Adult male Hooded Merganser
Photo: Justin Flint, CC BY 4.0 via iNaturalist

Hooded Mergansers are winter birds in District of Columbia: the first arrive in early November, they are common by mid November, peak in mid January (8.2% of checklists), and most are gone by late March.

When to look

First arrivalsNov 1-7early November
Common byNov 15-21mid November
PeakJan 15-21mid January
Most gone byMar 22-31late March

Best: mid January. First arrivals early November; most are gone by late March. Peak: on about 8.2% of District of Columbia checklists.

  1. Janpeak season
  2. Febpeak season
  3. Marcommon
  4. Apruncommon
  5. Mayrare
  6. Junrare
  7. Julrare
  8. Augnot usually seen
  9. Sepnot usually seen
  10. Octrare
  11. Novcommon
  12. Deccommon

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

0%5%10%Jan 1-7: 7.0% of 3043 checklistsJan 8-14: 8.2% of 2367 checklistsJan 15-21: 9.9% of 2140 checklistsJan 22-31: 7.0% of 2777 checklistsFeb 1-7: 7.8% of 2012 checklistsFeb 8-14: 5.0% of 1997 checklistsFeb 15-21: 5.0% of 2544 checklistsFeb 22-28: 5.6% of 2252 checklistsMar 1-7: 3.9% of 2282 checklistsMar 8-14: 3.7% of 2350 checklistsMar 15-21: 2.1% of 2432 checklistsMar 22-31: 2.8% of 3898 checklistsApr 1-7: 3.0% of 3221 checklistsApr 8-14: 1.3% of 3396 checklistsApr 15-21: 0.8% of 3718 checklistsApr 22-30: 0.7% of 5725 checklistsMay 1-7: 0.4% of 5415 checklistsMay 8-14: 0.2% of 5268 checklistsMay 15-21: 0% of 3741 checklistsMay 22-31: 0.7% of 3605 checklistsJun 1-7: 0.4% of 1902 checklistsJun 8-14: 0% of 1762 checklistsJun 15-21: 0.5% of 1637 checklistsJun 22-30: 0.5% of 1727 checklistsJul 1-7: 0.5% of 1471 checklistsJul 8-14: 0.2% of 1353 checklistsJul 15-21: 0% of 1297 checklistsJul 22-31: 0.3% of 1980 checklistsAug 1-7: 0% of 1465 checklistsAug 8-14: 0% of 1311 checklistsAug 15-21: 0% of 1669 checklistsAug 22-31: 0.1% of 2631 checklistsSep 1-7: 0.1% of 2482 checklistsSep 8-14: 0% of 2622 checklistsSep 15-21: 0.1% of 2661 checklistsSep 22-30: 0.1% of 3393 checklistsOct 1-7: 0.1% of 2457 checklistsOct 8-14: 0.2% of 2487 checklistsOct 15-21: 0.3% of 2201 checklistsOct 22-31: 1.0% of 2639 checklistsNov 1-7: 1.6% of 2074 checklistsNov 8-14: 2.4% of 1967 checklistsNov 15-21: 3.4% of 1832 checklistsNov 22-30: 3.6% of 2064 checklistsDec 1-7: 7.1% of 1773 checklistsDec 8-14: 4.9% of 2132 checklistsDec 15-21: 5.3% of 2009 checklistsDec 22-31: 5.5% of 2574 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 District of Columbia 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 District of Columbia

Best counties

Share of checklists at the peak
  1. District of Columbia CountyBest mid January · 2140 checklists that week, 121,721 in all8.2%

Best spots

Share of checklists at the peak
  1. George Washington Memorial ParkwayDistrict of Columbia County, best the second week of January · 36 checklists that week, 1,054 in all59%
  2. Heritage IslandDistrict of Columbia County, best the second week of January · 98 checklists that week, 3,356 in all44%
  3. Lyndon Baines Johnson Memorial Grove on the PotomacDistrict of Columbia County, best late January · 66 checklists that week, 1,852 in all30%
  4. Tide Lock ParkDistrict of Columbia County, best mid January · 31 checklists that week, 370 in all24%
  5. Kingman LakeDistrict of Columbia County, best the second week of February · 45 checklists that week, 2,256 in all18%

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

Best time of day

In District of Columbia, the Hooded Merganser is most often listed on checklists started between 8 and 10 am (2.9% of those checklists).

0%1%2%3%12 am: too few checklists (27) to judge1 am: too few checklists (29) to judge2 am: too few checklists (23) to judge3 am: too few checklists (21) to judge4 am: too few checklists (31) to judge5 am: too few checklists (631) to judge6 am: 1.6% of 7391 checklists7 am: 2.5% of 18497 checklists8 am: 3.0% of 18527 checklists9 am: 2.8% of 13285 checklists10 am: 2.5% of 10722 checklists11 am: 2.5% of 8880 checklists12 pm: 2.4% of 7456 checklists1 pm: 2.4% of 6394 checklists2 pm: 2.2% of 6063 checklists3 pm: 2.0% of 6112 checklists4 pm: 1.2% of 5809 checklists5 pm: 0.5% of 5409 checklists6 pm: 0.2% of 3982 checklists7 pm: too few checklists (1887) to judge8 pm: too few checklists (423) to judge9 pm: too few checklists (79) to judge10 pm: too few checklists (44) to judge11 pm: too few checklists (33) 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
January7.0%8.2%9.9%7.0%
February7.8%5.0%5.0%5.6%
March3.9%3.7%2.1%2.8%
April3.0%1.3%0.8%0.7%
May0.4%0.2%0%0.7%
June0.4%0%0.5%0.5%
July0.5%0.2%0%0.3%
August0%0%0%0.1%
September0.1%0%0.1%0.1%
October0.1%0.2%0.3%1.0%
November1.6%2.4%3.4%3.6%
December7.1%4.9%5.3%5.5%

Neighboring states

  • Maryland: arrives late October, 1 week earlier than District of Columbia
  • Virginia: arrives late October, 1 week earlier than District of Columbia
  • Delaware: arrives early November, in the same week than District of Columbia
  • Pennsylvania: arrives late October, 1 week earlier than District of Columbia

Common questions

When do Hooded Mergansers arrive in District of Columbia?
Hooded Mergansers are winter birds in District of Columbia: the first arrive in early November, they are common by mid November, peak in mid January (8.2% of checklists), and most are gone by late March.
When do Hooded Mergansers leave District of Columbia?
Most Hooded Mergansers have left District of Columbia 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 Hooded Merganser in District of Columbia?
The Hooded Merganser is reported most often in mid January, on about 8.2% of District of Columbia checklists.
Where in District of Columbia are Hooded Mergansers seen most often?
By county, District of Columbia County have the highest peak reporting rates for the Hooded Merganser (counties with at least 200 checklists).