Barn Swallows reach South Dakota in mid April, are common by early May, peak in the second week of August (37% of checklists), and most are gone by the second week of September.
When to look
First arrivalsApr 15-21mid April
Common byMay 1-7early May
PeakAug 8-14the second week of August
Most gone bySep 8-14the second week of September
Best: the second week of August. First arrivals mid April; most are gone by the second week of September. Peak: on about 37% of South Dakota checklists.
Jannot usually seen
Febnot usually seen
Marnot usually seen
Apruncommon
Maypeak season
Junpeak season
Julpeak season
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 South 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.
SertomaMinnehaha County, best early June · 20 checklists that week, 764 in all76%
Canyon Lake ParkPennington County, best mid July · 58 checklists that week, 2,659 in all73%
Wind Cave National ParkCuster County, best late May · 34 checklists that week, 475 in all69%
Busy spots report more of everything; compare the checklist counts before you drive anywhere.
Best time of day
In South Dakota, the Barn Swallow is most often listed on checklists started between 6 and 8 am (24% 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
0.1%
0.8%
2.2%
10%
May
22%
30%
35%
33%
June
28%
26%
27%
30%
July
32%
31%
32%
36%
August
37%
37%
36%
34%
September
30%
25%
14%
7.3%
October
6.5%
1.4%
0.7%
0.1%
November
0%
0%
0%
0%
December
0%
0%
0%
0%
Neighboring states
Nebraska: arrives the second week of April, 1 week earlier than South Dakota
North Dakota: arrives late April, 1 week later than South Dakota
Minnesota: arrives mid April, in the same week than South Dakota
Iowa: arrives the second week of April, 1 week earlier than South Dakota
Common questions
When do Barn Swallows arrive in South Dakota?
Barn Swallows reach South Dakota in mid April, are common by early May, peak in the second week of August (37% of checklists), and most are gone by the second week of September.
When do Barn Swallows leave South Dakota?
Most Barn Swallows have left South Dakota by the second week of September, when reports fall below half their usual rate. Stragglers are still reported until early October.
When is the best time to see a Barn Swallow in South Dakota?
The Barn Swallow is reported most often in the second week of August, on about 37% of South Dakota checklists.
Where in South Dakota are Barn Swallows seen most often?
By county, Union County, Hutchinson County, and Sanborn County have the highest peak reporting rates for the Barn Swallow (counties with at least 200 checklists).