Bank Swallows arrive in Wisconsin in late April, peak in mid May (3.8% of checklists), and most are gone by late August.
When to look
First arrivalsApr 22-30late April
Common byApr 22-30late April
PeakMay 15-21mid May
Most gone byAug 22-31late August
Best: mid May. First arrivals late April; most are gone by late August. Peak: on about 3.8% of Wisconsin checklists.
Jannot usually seen
Febnot usually seen
Marnot usually seen
Aprcommon
Maypeak season
Junpeak season
Julpeak season
Augpeak season
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 Wisconsin 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.
Marquette CountyBest early August · 73 checklists that week, 3,706 in all14%
Jefferson CountyBest the second week of August · 406 checklists that week, 31,378 in all14%
Dodge CountyBest the second week of August · 811 checklists that week, 34,980 in all12%
Manitowoc CountyBest the second week of July · 370 checklists that week, 26,017 in all11%
Kenosha CountyBest mid May · 504 checklists that week, 11,654 in all11%
Brown CountyBest the second week of July · 545 checklists that week, 36,306 in all10%
Best spots
Share of checklists at the peak
Warnimont ParkMilwaukee County, best the second week of June · 32 checklists that week, 2,226 in all89%
Warnimont Park (north)Milwaukee County, best the second week of May · 47 checklists that week, 251 in all73%
Lake Mills Wildlife AreaJefferson County, best the second week of August · 21 checklists that week, 1,592 in all72%
Sheridan Park (south)Milwaukee County, best the second week of May · 24 checklists that week, 349 in all68%
Warnimont Park (north)Milwaukee County, best the second week of May · 53 checklists that week, 171 in all68%
Busy spots report more of everything; compare the checklist counts before you drive anywhere.
Best time of day
In Wisconsin, the Bank Swallow is most often listed on checklists started between 5 and 7 am (2.1% 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%
0.1%
0.4%
1.7%
May
2.8%
3.7%
4.2%
3.7%
June
2.8%
2.5%
2.2%
2.3%
July
2.7%
3.2%
3.2%
3.2%
August
3.0%
3.3%
2.9%
1.4%
September
0.6%
0.2%
0.1%
0%
October
0.1%
0%
0%
0%
November
0%
0%
0%
0%
December
0%
0%
0%
0%
Neighboring states
Illinois: arrives mid April, 1 week earlier than Wisconsin
Iowa: arrives late April, in the same week than Wisconsin
Michigan: arrives late April, in the same week than Wisconsin
Minnesota: arrives early May, 1 week later than Wisconsin
Common questions
When do Bank Swallows arrive in Wisconsin?
Bank Swallows arrive in Wisconsin in late April, peak in mid May (3.8% of checklists), and most are gone by late August.
When do Bank Swallows leave Wisconsin?
Most Bank Swallows have left Wisconsin by late August, when reports fall below half their usual rate.
When is the best time to see a Bank Swallow in Wisconsin?
The Bank Swallow is reported most often in mid May, on about 3.8% of Wisconsin checklists.
Where in Wisconsin are Bank Swallows seen most often?
By county, Marquette County, Jefferson County, and Dodge County have the highest peak reporting rates for the Bank Swallow (counties with at least 200 checklists).