Great-tailed Grackles arrive in Wyoming in late March, peak in the second week of May (1.7% of checklists), and most are gone by the second week of July.
When to look
First arrivalsMar 22-31late March
Common byMar 22-31late March
PeakMay 8-14the second week of May
Most gone byJul 8-14the second week of July
Best: the second week of May. First arrivals late March; most are gone by the second week of July. Peak: on about 1.7% of Wyoming checklists.
Jannot usually seen
Febrare
Maruncommon
Aprpeak season
Maypeak season
Juncommon
Juluncommon
Auguncommon
Seprare
Octrare
Novrare
Decrare
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.
Meeboer LakeAlbany County, best late April · 23 checklists that week, 300 in all11%
Lions ParkLaramie County, best late June · 20 checklists that week, 1,309 in all8.7%
Optomist ParkAlbany County, best late May · 110 checklists that week, 2,101 in all8.6%
Busy spots report more of everything; compare the checklist counts before you drive anywhere.
Best time of day
In Wyoming, the Great-tailed Grackle is most often listed on checklists started between 6 and 8 am (0.8% 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
0.1%
0.1%
0.1%
0.1%
February
0%
0.1%
0.2%
0.2%
March
0.2%
0.1%
0.1%
0.6%
April
0.8%
0.8%
0.9%
1.6%
May
1.5%
1.6%
1.8%
1.5%
June
0.9%
0.5%
0.3%
0.5%
July
0.7%
0.4%
0.5%
0.4%
August
0.3%
0.2%
0.2%
0.1%
September
0.1%
0.1%
0.1%
0.1%
October
0.1%
0.1%
0.1%
0.1%
November
0.1%
0.1%
0.2%
0.2%
December
0.2%
0%
0.2%
0.1%
Neighboring states
Colorado: arrives the second week of March, 2 weeks earlier than Wyoming
Utah: arrives late March, in the same week than Wyoming
Nebraska: arrives mid March, 1 week earlier than Wyoming
New Mexico: arrives mid March, 1 week earlier than Wyoming
Common questions
When do Great-tailed Grackles arrive in Wyoming?
Great-tailed Grackles arrive in Wyoming in late March, peak in the second week of May (1.7% of checklists), and most are gone by the second week of July.
When do Great-tailed Grackles leave Wyoming?
Most Great-tailed Grackles have left Wyoming by the second week of July, when reports fall below half their usual rate.
When is the best time to see a Great-tailed Grackle in Wyoming?
The Great-tailed Grackle is reported most often in the second week of May, on about 1.7% of Wyoming checklists.
Where in Wyoming are Great-tailed Grackles seen most often?
By county, Niobrara County, Goshen County, and Laramie County have the highest peak reporting rates for the Great-tailed Grackle (counties with at least 200 checklists).