WhenToBird

Bucephala albeola · Anatidae

When Do Buffleheads Arrive in Wyoming?

Adult Bufflehead
Photo: Robert Harris, CC BY 4.0 via iNaturalist

Buffleheads are winter birds in Wyoming: the first arrive in mid August, they are common by early October, peak in the second week of November (11% of checklists), and most are gone by the second week of June.

When to look

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

Best: the second week of November. First arrivals mid August; most are gone by the second week of June. Peak: on about 11% of Wyoming checklists.

  1. Januncommon
  2. Febuncommon
  3. Marcommon
  4. Aprpeak season
  5. Maycommon
  6. Jununcommon
  7. Julrare
  8. Augrare
  9. Sepuncommon
  10. Octpeak season
  11. Novpeak season
  12. Decuncommon

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

0%5%10%15%Jan 1-7: 3.3% of 2543 checklistsJan 8-14: 3.8% of 2114 checklistsJan 15-21: 2.8% of 1984 checklistsJan 22-31: 3.2% of 2605 checklistsFeb 1-7: 2.8% of 1940 checklistsFeb 8-14: 2.8% of 1954 checklistsFeb 15-21: 3.0% of 2575 checklistsFeb 22-28: 3.1% of 1932 checklistsMar 1-7: 3.1% of 2486 checklistsMar 8-14: 4.2% of 2535 checklistsMar 15-21: 5.6% of 2726 checklistsMar 22-31: 7.1% of 4349 checklistsApr 1-7: 7.5% of 3300 checklistsApr 8-14: 9.8% of 3500 checklistsApr 15-21: 10% of 3701 checklistsApr 22-30: 8.8% of 5887 checklistsMay 1-7: 6.6% of 5341 checklistsMay 8-14: 4.2% of 6910 checklistsMay 15-21: 3.3% of 6884 checklistsMay 22-31: 2.8% of 10652 checklistsJun 1-7: 2.9% of 6807 checklistsJun 8-14: 2.3% of 6714 checklistsJun 15-21: 2.3% of 6708 checklistsJun 22-30: 1.9% of 8160 checklistsJul 1-7: 1.1% of 5755 checklistsJul 8-14: 1.3% of 5379 checklistsJul 15-21: 1.4% of 5299 checklistsJul 22-31: 1.2% of 6830 checklistsAug 1-7: 1.0% of 4581 checklistsAug 8-14: 0.7% of 4625 checklistsAug 15-21: 1.2% of 4466 checklistsAug 22-31: 1.6% of 6562 checklistsSep 1-7: 1.3% of 4543 checklistsSep 8-14: 1.2% of 4652 checklistsSep 15-21: 1.6% of 4186 checklistsSep 22-30: 1.8% of 5301 checklistsOct 1-7: 2.1% of 3248 checklistsOct 8-14: 3.6% of 3010 checklistsOct 15-21: 8.0% of 2624 checklistsOct 22-31: 10% of 3170 checklistsNov 1-7: 13% of 2110 checklistsNov 8-14: 12% of 2153 checklistsNov 15-21: 9.5% of 1971 checklistsNov 22-30: 5.3% of 2136 checklistsDec 1-7: 3.3% of 1646 checklistsDec 8-14: 2.8% of 1609 checklistsDec 15-21: 2.5% of 1954 checklistsDec 22-31: 2.4% of 2392 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 Wyoming 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 Wyoming

Best counties

Share of checklists at the peak
  1. Carbon CountyBest the second week of November · 42 checklists that week, 6,429 in all33%
  2. Platte CountyBest mid November · 34 checklists that week, 1,645 in all25%
  3. Natrona CountyBest mid November · 53 checklists that week, 5,810 in all25%
  4. Campbell CountyBest early November · 17 checklists that week, 2,801 in all25%
  5. Weston CountyBest late October · 55 checklists that week, 2,297 in all23%
  6. Lincoln CountyBest the second week of November · 19 checklists that week, 3,169 in all22%

Best spots

Share of checklists at the peak
  1. Twin Buttes LakeAlbany County, best the second week of November · 40 checklists that week, 405 in all96%
  2. National Elk RefugeTeton County, best late January · 25 checklists that week, 1,797 in all90%
  3. Dry LakeFremont County, best the second week of November · 22 checklists that week, 276 in all86%
  4. Yellowstone National Park (Arnica Creek)Teton County, best mid June · 20 checklists that week, 201 in all78%
  5. Ray ReservoirFremont County, best late April · 49 checklists that week, 426 in all73%
  6. Wyoming Hereford Ranch Reservoir Number OneLaramie County, best early April · 30 checklists that week, 1,242 in all71%

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

Best time of day

In Wyoming, the Bufflehead is most often listed on checklists started between 1 and 3 pm (4.9% of those checklists).

0%2%4%6%12 am: too few checklists (59) to judge1 am: too few checklists (76) to judge2 am: too few checklists (86) to judge3 am: too few checklists (79) to judge4 am: too few checklists (326) to judge5 am: too few checklists (2271) to judge6 am: 1.3% of 8808 checklists7 am: 2.3% of 18458 checklists8 am: 2.9% of 22143 checklists9 am: 3.3% of 21499 checklists10 am: 4.3% of 19425 checklists11 am: 4.8% of 16017 checklists12 pm: 4.4% of 13868 checklists1 pm: 4.9% of 12984 checklists2 pm: 4.9% of 12605 checklists3 pm: 4.8% of 11821 checklists4 pm: 4.2% of 10571 checklists5 pm: 3.9% of 8746 checklists6 pm: 2.7% of 6707 checklists7 pm: 1.8% of 4890 checklists8 pm: too few checklists (2323) to judge9 pm: too few checklists (554) to judge10 pm: too few checklists (134) to judge11 pm: too few checklists (59) 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
January3.3%3.8%2.8%3.2%
February2.8%2.8%3.0%3.1%
March3.1%4.2%5.6%7.1%
April7.5%9.8%10%8.8%
May6.6%4.2%3.3%2.8%
June2.9%2.3%2.3%1.9%
July1.1%1.3%1.4%1.2%
August1.0%0.7%1.2%1.6%
September1.3%1.2%1.6%1.8%
October2.1%3.6%8.0%10%
November13%12%9.5%5.3%
December3.3%2.8%2.5%2.4%

Neighboring states

  • Colorado: arrives the second week of October, 7 weeks later than Wyoming
  • Utah: arrives mid October, 8 weeks later than Wyoming
  • Montana: arrives mid August, in the same week than Wyoming
  • Idaho: arrives early August, 2 weeks earlier than Wyoming

Common questions

When do Buffleheads arrive in Wyoming?
Buffleheads are winter birds in Wyoming: the first arrive in mid August, they are common by early October, peak in the second week of November (11% of checklists), and most are gone by the second week of June.
When do Buffleheads leave Wyoming?
Most Buffleheads have left Wyoming by the second week of June, when reports fall below half their usual rate. Stragglers are still reported until late July.
When is the best time to see a Bufflehead in Wyoming?
The Bufflehead is reported most often in the second week of November, on about 11% of Wyoming checklists.
Where in Wyoming are Buffleheads seen most often?
By county, Carbon County, Platte County, and Natrona County have the highest peak reporting rates for the Bufflehead (counties with at least 200 checklists).