Wilson's Warblers mostly pass through North Dakota: they arrive in the second week of August, peak in early September (11% of checklists), and most are gone by mid September.
When to look
First arrivalsAug 8-14the second week of August
Common byAug 8-14the second week of August
PeakSep 1-7early September
Most gone bySep 15-21mid September
Best: early September. First arrivals the second week of August; most are gone by mid September. Peak: on about 11% of North Dakota checklists.
Jannot usually seen
Febnot usually seen
Marnot usually seen
Aprnot usually seen
Mayuncommon
Jununcommon
Julnot usually seen
Augpeak season
Seppeak season
Octrare
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 North Dakota 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.
Adams CountyBest the second week of September · 13 checklists that week, 683 in all36%
Wells CountyBest mid August · 11 checklists that week, 416 in all32%
McIntosh CountyBest late August · 30 checklists that week, 400 in all23%
Burke CountyBest late August · 36 checklists that week, 941 in all23%
Logan CountyBest mid September · 13 checklists that week, 443 in all23%
Ward CountyBest early September · 89 checklists that week, 5,793 in all21%
Best spots
Share of checklists at the peak
Treefoil ParkCass County, best late August · 51 checklists that week, 1,125 in all57%
Oak ParkWard County, best early September · 30 checklists that week, 777 in all49%
BOR LandsStark County, best the second week of September · 20 checklists that week, 357 in all46%
Sertoma ParkGrand Forks County, best late August · 25 checklists that week, 599 in all44%
Sertoma Park (southeast)Grand Forks County, best late May · 35 checklists that week, 403 in all32%
Busy spots report more of everything; compare the checklist counts before you drive anywhere.
Best time of day
In North Dakota, the Wilson's Warbler is most often listed on checklists started between 6 and 8 am (2.3% 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%
0.1%
May
0.1%
2.1%
6.3%
3.8%
June
0.2%
0%
0%
0%
July
0%
0%
0%
0%
August
0%
0.5%
5.9%
13%
September
11%
7.6%
4.4%
1.1%
October
0.2%
0.3%
0%
0.1%
November
0%
0%
0%
0%
December
0%
0%
0%
0%
Neighboring states
South Dakota: arrives mid August, 1 week later than North Dakota
Minnesota: arrives early May, 13 weeks earlier than North Dakota
Nebraska: arrives mid August, 1 week later than North Dakota
Iowa: arrives early May, 13 weeks earlier than North Dakota
Common questions
When do Wilson's Warblers arrive in North Dakota?
Wilson's Warblers mostly pass through North Dakota: they arrive in the second week of August, peak in early September (11% of checklists), and most are gone by mid September.
When do Wilson's Warblers leave North Dakota?
Most Wilson's Warblers have left North Dakota by mid September, when reports fall below half their usual rate. Stragglers are still reported until late September.
When is the best time to see a Wilson's Warbler in North Dakota?
The Wilson's Warbler is reported most often in early September, on about 11% of North Dakota checklists.
Where in North Dakota are Wilson's Warblers seen most often?
By county, Adams County, Wells County, and McIntosh County have the highest peak reporting rates for the Wilson's Warbler (counties with at least 200 checklists).