WhenToBird

Lophodytes cucullatus · Anatidae

When Do Hooded Mergansers Arrive in Washington?

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

Hooded Mergansers are winter birds in Washington: the first arrive in early August, they are common by mid October, peak in mid November (14% of checklists), and most are gone by the second week of April.

When to look

First arrivalsAug 1-7early August
Common byOct 15-21mid October
PeakNov 15-21mid November
Most gone byApr 8-14the second week of April

Best: mid November. First arrivals early August; most are gone by the second week of April. Peak: on about 14% of Washington checklists.

  1. Janpeak season
  2. Febpeak season
  3. Marcommon
  4. Aprcommon
  5. Mayuncommon
  6. Junrare
  7. Juluncommon
  8. Auguncommon
  9. Sepuncommon
  10. Octcommon
  11. Novpeak season
  12. Decpeak season

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

0%5%10%15%Jan 1-7: 13% of 41928 checklistsJan 8-14: 12% of 31152 checklistsJan 15-21: 12% of 31753 checklistsJan 22-31: 12% of 42530 checklistsFeb 1-7: 11% of 29739 checklistsFeb 8-14: 9.3% of 32746 checklistsFeb 15-21: 8.9% of 40328 checklistsFeb 22-28: 11% of 28432 checklistsMar 1-7: 10% of 30758 checklistsMar 8-14: 10% of 29368 checklistsMar 15-21: 8.9% of 32580 checklistsMar 22-31: 8.1% of 45614 checklistsApr 1-7: 7.0% of 33997 checklistsApr 8-14: 6.3% of 34729 checklistsApr 15-21: 5.1% of 38474 checklistsApr 22-30: 4.2% of 52185 checklistsMay 1-7: 3.4% of 44236 checklistsMay 8-14: 2.7% of 48708 checklistsMay 15-21: 2.5% of 41742 checklistsMay 22-31: 2.2% of 57082 checklistsJun 1-7: 1.9% of 39193 checklistsJun 8-14: 1.9% of 36042 checklistsJun 15-21: 1.9% of 34003 checklistsJun 22-30: 1.7% of 39711 checklistsJul 1-7: 1.6% of 31949 checklistsJul 8-14: 1.8% of 29086 checklistsJul 15-21: 1.9% of 28045 checklistsJul 22-31: 2.2% of 38275 checklistsAug 1-7: 2.8% of 28846 checklistsAug 8-14: 2.9% of 28036 checklistsAug 15-21: 3.1% of 27614 checklistsAug 22-31: 3.5% of 40356 checklistsSep 1-7: 3.5% of 31214 checklistsSep 8-14: 3.5% of 27795 checklistsSep 15-21: 3.8% of 29677 checklistsSep 22-30: 4.3% of 35241 checklistsOct 1-7: 4.5% of 28605 checklistsOct 8-14: 4.7% of 28655 checklistsOct 15-21: 6.2% of 24643 checklistsOct 22-31: 9.5% of 34874 checklistsNov 1-7: 12% of 25658 checklistsNov 8-14: 13% of 25700 checklistsNov 15-21: 15% of 24331 checklistsNov 22-30: 14% of 32784 checklistsDec 1-7: 13% of 24099 checklistsDec 8-14: 13% of 23339 checklistsDec 15-21: 12% of 27666 checklistsDec 22-31: 13% of 42130 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 Washington 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 Washington

Best counties

Share of checklists at the peak
  1. Skamania CountyBest the second week of December · 93 checklists that week, 10,140 in all42%
  2. Wahkiakum CountyBest mid December · 53 checklists that week, 5,618 in all28%
  3. Jefferson CountyBest late November · 1185 checklists that week, 59,663 in all27%
  4. Thurston CountyBest late November · 1548 checklists that week, 68,352 in all26%
  5. Clark CountyBest the second week of March · 1067 checklists that week, 53,250 in all25%
  6. Franklin CountyBest late November · 159 checklists that week, 7,970 in all24%

Best spots

Share of checklists at the peak
  1. Kitsap Lake ParkKitsap County, best early January · 43 checklists that week, 426 in all94%
  2. Entrance ChannelThurston County, best mid November · 62 checklists that week, 2,706 in all90%
  3. Pitship PointClallam County, best mid December · 25 checklists that week, 1,307 in all86%
  4. Kah Tai Lagoon Nature ParkJefferson County, best early November · 45 checklists that week, 2,811 in all85%
  5. Silicosaska ParkChelan County, best early January · 23 checklists that week, 211 in all84%

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

Best time of day

In Washington, the Hooded Merganser is most often listed on checklists started between 1 and 3 pm (8.1% of those checklists).

0%5%10%12 am: too few checklists (796) to judge1 am: too few checklists (776) to judge2 am: too few checklists (709) to judge3 am: too few checklists (901) to judge4 am: too few checklists (3221) to judge5 am: too few checklists (16576) to judge6 am: 3.9% of 56744 checklists7 am: 5.5% of 133294 checklists8 am: 7.0% of 184196 checklists9 am: 7.3% of 186303 checklists10 am: 7.5% of 177063 checklists11 am: 7.5% of 154936 checklists12 pm: 7.7% of 138061 checklists1 pm: 8.1% of 127449 checklists2 pm: 8.1% of 121511 checklists3 pm: 7.4% of 107793 checklists4 pm: 5.7% of 82862 checklists5 pm: 3.9% of 57183 checklists6 pm: 2.9% of 39886 checklists7 pm: too few checklists (26969) to judge8 pm: too few checklists (12427) to judge9 pm: too few checklists (3658) to judge10 pm: too few checklists (1500) to judge11 pm: too few checklists (834) 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
January13%12%12%12%
February11%9.3%8.9%11%
March10%10%8.9%8.1%
April7.0%6.3%5.1%4.2%
May3.4%2.7%2.5%2.2%
June1.9%1.9%1.9%1.7%
July1.6%1.8%1.9%2.2%
August2.8%2.9%3.1%3.5%
September3.5%3.5%3.8%4.3%
October4.5%4.7%6.2%9.5%
November12%13%15%14%
December13%13%12%13%

Neighboring states

  • Oregon: arrives the second week of July, 3 weeks earlier than Washington
  • Idaho: arrives the second week of October, 9 weeks later than Washington
  • Montana: arrives mid July, 2 weeks earlier than Washington
  • Nevada: arrives late October, 11 weeks later than Washington

Common questions

When do Hooded Mergansers arrive in Washington?
Hooded Mergansers are winter birds in Washington: the first arrive in early August, they are common by mid October, peak in mid November (14% of checklists), and most are gone by the second week of April.
When do Hooded Mergansers leave Washington?
Most Hooded Mergansers have left Washington by the second week of April, when reports fall below half their usual rate. Stragglers are still reported until the second week of May.
When is the best time to see a Hooded Merganser in Washington?
The Hooded Merganser is reported most often in mid November, on about 14% of Washington checklists.
Where in Washington are Hooded Mergansers seen most often?
By county, Skamania County, Wahkiakum County, and Jefferson County have the highest peak reporting rates for the Hooded Merganser (counties with at least 200 checklists).