WhenToBird

Lophodytes cucullatus · Anatidae

When Do Hooded Mergansers Arrive in Vermont?

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

Hooded Mergansers are winter birds in Vermont: the first arrive in mid July, they are common by mid October, peak in late March (13% of checklists), and most are gone by early May.

When to look

First arrivalsJul 15-21mid July
Common byOct 15-21mid October
PeakMar 22-31late March
Most gone byMay 1-7early May

Best: late March. First arrivals mid July; most are gone by early May. Peak: on about 13% of Vermont checklists.

  1. Januncommon
  2. Febuncommon
  3. Marpeak season
  4. Aprpeak season
  5. Mayuncommon
  6. Junrare
  7. Juluncommon
  8. Auguncommon
  9. Sepuncommon
  10. Octcommon
  11. Novpeak season
  12. Deccommon

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

0%5%10%15%Jan 1-7: 5.1% of 12234 checklistsJan 8-14: 4.4% of 8293 checklistsJan 15-21: 3.6% of 7885 checklistsJan 22-31: 3.0% of 10534 checklistsFeb 1-7: 2.7% of 7212 checklistsFeb 8-14: 2.9% of 8144 checklistsFeb 15-21: 2.3% of 10480 checklistsFeb 22-28: 3.6% of 7932 checklistsMar 1-7: 5.6% of 8192 checklistsMar 8-14: 8.0% of 9383 checklistsMar 15-21: 12% of 10620 checklistsMar 22-31: 14% of 16257 checklistsApr 1-7: 13% of 12568 checklistsApr 8-14: 10% of 14677 checklistsApr 15-21: 8.3% of 14106 checklistsApr 22-30: 6.2% of 19617 checklistsMay 1-7: 4.1% of 18143 checklistsMay 8-14: 2.5% of 19626 checklistsMay 15-21: 2.0% of 17779 checklistsMay 22-31: 2.0% of 20310 checklistsJun 1-7: 1.6% of 11493 checklistsJun 8-14: 2.0% of 10215 checklistsJun 15-21: 1.3% of 9951 checklistsJun 22-30: 1.3% of 11050 checklistsJul 1-7: 1.1% of 8690 checklistsJul 8-14: 1.8% of 7679 checklistsJul 15-21: 1.8% of 7687 checklistsJul 22-31: 2.4% of 10712 checklistsAug 1-7: 2.5% of 7703 checklistsAug 8-14: 2.0% of 7743 checklistsAug 15-21: 2.5% of 8314 checklistsAug 22-31: 2.5% of 12428 checklistsSep 1-7: 2.2% of 9526 checklistsSep 8-14: 2.1% of 8493 checklistsSep 15-21: 2.3% of 8283 checklistsSep 22-30: 1.9% of 10352 checklistsOct 1-7: 2.0% of 8802 checklistsOct 8-14: 2.3% of 9088 checklistsOct 15-21: 3.1% of 7739 checklistsOct 22-31: 7.7% of 10907 checklistsNov 1-7: 10% of 7868 checklistsNov 8-14: 12% of 7223 checklistsNov 15-21: 14% of 7224 checklistsNov 22-30: 11% of 8375 checklistsDec 1-7: 10% of 6580 checklistsDec 8-14: 7.1% of 6800 checklistsDec 15-21: 3.7% of 8334 checklistsDec 22-31: 3.7% of 10579 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 Vermont 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.

Embed this map on your site

Where in Vermont

Best counties

Share of checklists at the peak
  1. Windsor CountyBest mid November · 1119 checklists that week, 73,702 in all27%
  2. Windham CountyBest late March · 1692 checklists that week, 39,105 in all21%
  3. Orleans CountyBest late November · 194 checklists that week, 11,785 in all21%
  4. Bennington CountyBest late March · 616 checklists that week, 21,621 in all20%
  5. Grand Isle CountyBest mid March · 221 checklists that week, 8,507 in all17%
  6. Orange CountyBest the second week of April · 475 checklists that week, 16,964 in all16%

Best spots

Share of checklists at the peak
  1. Colchester PondChittenden County, best late November · 77 checklists that week, 3,341 in all96%
  2. LewistonWindsor County, best the second week of November · 20 checklists that week, 597 in all90%
  3. South Stream Wildlife Management AreaBennington County, best early April · 20 checklists that week, 347 in all87%
  4. Kilowatt ParkWindsor County, best mid November · 141 checklists that week, 2,625 in all85%
  5. Berlin PondWashington County, best late March · 62 checklists that week, 1,957 in all83%

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

Best time of day

In Vermont, the Hooded Merganser is most often listed on checklists started between 10 am and 12 pm (6.4% of those checklists).

0%2%4%6%8%12 am: too few checklists (384) to judge1 am: too few checklists (418) to judge2 am: too few checklists (568) to judge3 am: too few checklists (1183) to judge4 am: too few checklists (3460) to judge5 am: 2.0% of 10340 checklists6 am: 3.5% of 30951 checklists7 am: 3.9% of 64150 checklists8 am: 4.4% of 70252 checklists9 am: 5.8% of 55280 checklists10 am: 6.4% of 47111 checklists11 am: 6.4% of 37615 checklists12 pm: 5.8% of 32195 checklists1 pm: 6.0% of 30185 checklists2 pm: 6.0% of 29679 checklists3 pm: 5.7% of 26483 checklists4 pm: 5.0% of 20110 checklists5 pm: 4.0% of 15993 checklists6 pm: 3.0% of 12110 checklists7 pm: too few checklists (8203) to judge8 pm: too few checklists (4425) to judge9 pm: too few checklists (1829) to judge10 pm: too few checklists (597) to judge11 pm: too few checklists (309) 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
January5.1%4.4%3.6%3.0%
February2.7%2.9%2.3%3.6%
March5.6%8.0%12%14%
April13%10%8.3%6.2%
May4.1%2.5%2.0%2.0%
June1.6%2.0%1.3%1.3%
July1.1%1.8%1.8%2.4%
August2.5%2.0%2.5%2.5%
September2.2%2.1%2.3%1.9%
October2.0%2.3%3.1%7.7%
November10%12%14%11%
December10%7.1%3.7%3.7%

Neighboring states

  • New Hampshire: arrives early March, 18 weeks earlier than Vermont
  • Massachusetts: arrives mid October, 12 weeks later than Vermont
  • Connecticut: arrives mid October, 12 weeks later than Vermont
  • Rhode Island: arrives mid October, 12 weeks later than Vermont

Common questions

When do Hooded Mergansers arrive in Vermont?
Hooded Mergansers are winter birds in Vermont: the first arrive in mid July, they are common by mid October, peak in late March (13% of checklists), and most are gone by early May.
When do Hooded Mergansers leave Vermont?
Most Hooded Mergansers have left Vermont by early May, when reports fall below half their usual rate. Stragglers are still reported until early June.
When is the best time to see a Hooded Merganser in Vermont?
The Hooded Merganser is reported most often in late March, on about 13% of Vermont checklists.
Where in Vermont are Hooded Mergansers seen most often?
By county, Windsor County, Windham County, and Orleans County have the highest peak reporting rates for the Hooded Merganser (counties with at least 200 checklists).