Wilson's Phalaropes reach Wyoming in mid April, are common by late April, peak in the second week of May (9.2% of checklists), and most are gone by early September.
When to look
First arrivalsApr 15-21mid April
Common byApr 22-30late April
PeakMay 8-14the second week of May
Most gone bySep 1-7early September
Best: the second week of May. First arrivals mid April; most are gone by early September. Peak: on about 9.2% of Wyoming checklists.
Jannot usually seen
Febnot usually seen
Marnot usually seen
Aprcommon
Maypeak season
Juncommon
Julcommon
Augcommon
Sepuncommon
Octnot usually seen
Novnot usually seen
Decnot usually seen
Darker months: more checklists report it. Outlined: peak month.
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
0%few checklistsno data
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.
Alkali LakePark County, best the second week of May · 36 checklists that week, 722 in all78%
Ray ReservoirFremont County, best late May · 21 checklists that week, 426 in all69%
Busy spots report more of everything; compare the checklist counts before you drive anywhere.
Best time of day
In Wyoming, the Wilson's Phalarope is most often listed on checklists started between 6 and 8 pm (3.9% of those checklists).
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
Month
Days 1-7
8-14
15-21
22-end
January
0%
0%
0%
0%
February
0%
0%
0%
0%
March
0%
0%
0%
0%
April
0%
0%
0.1%
2.8%
May
9.0%
9.3%
9.4%
7.3%
June
4.0%
3.6%
4.4%
3.1%
July
2.9%
3.3%
3.9%
3.9%
August
3.4%
3.9%
3.9%
3.1%
September
2.2%
1.5%
0.6%
0.2%
October
0.1%
0%
0%
0%
November
0.1%
0%
0%
0%
December
0%
0%
0%
0%
Neighboring states
Colorado: arrives mid April, in the same week than Wyoming
Utah: arrives late April, 1 week later than Wyoming
Montana: arrives late April, 1 week later than Wyoming
Idaho: arrives late April, 1 week later than Wyoming
Common questions
When do Wilson's Phalaropes arrive in Wyoming?
Wilson's Phalaropes reach Wyoming in mid April, are common by late April, peak in the second week of May (9.2% of checklists), and most are gone by early September.
When do Wilson's Phalaropes leave Wyoming?
Most Wilson's Phalaropes have left Wyoming by early September, when reports fall below half their usual rate. Stragglers are still reported until the second week of September.
When is the best time to see a Wilson's Phalarope in Wyoming?
The Wilson's Phalarope is reported most often in the second week of May, on about 9.2% of Wyoming checklists.
Where in Wyoming are Wilson's Phalaropes seen most often?
By county, Campbell County, Goshen County, and Albany County have the highest peak reporting rates for the Wilson's Phalarope (counties with at least 200 checklists).