WhenToBird

Chaetura pelagica · Apodidae

When Do Chimney Swifts Arrive in Michigan?

Adult Chimney Swift
Photo: Ali Campbell, CC BY 4.0 via iNaturalist

Chimney Swifts reach Michigan in mid April, are common by early May, peak in early August (11% 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 1-7early August
Most gone bySep 8-14the second week of September

Best: early August. First arrivals mid April; most are gone by the second week of September. Peak: on about 11% of Michigan checklists.

  1. Jannot usually seen
  2. Febnot usually seen
  3. Marnot usually seen
  4. Apruncommon
  5. Maypeak season
  6. Junpeak season
  7. Julpeak season
  8. Augpeak season
  9. Sepcommon
  10. Octuncommon
  11. Novnot usually seen
  12. Decnot usually seen

Darker months: more checklists report it. Outlined: peak month.

0%5%10%15%Jan 1-7: 0% of 38160 checklistsJan 8-14: 0% of 24696 checklistsJan 15-21: 0% of 23771 checklistsJan 22-31: 0% of 31347 checklistsFeb 1-7: 0% of 23225 checklistsFeb 8-14: 0% of 27398 checklistsFeb 15-21: 0% of 36606 checklistsFeb 22-28: 0% of 27127 checklistsMar 1-7: 0% of 29700 checklistsMar 8-14: 0% of 31587 checklistsMar 15-21: 0% of 32118 checklistsMar 22-31: 0.1% of 47777 checklistsApr 1-7: 0% of 38557 checklistsApr 8-14: 0.1% of 42207 checklistsApr 15-21: 0.2% of 42759 checklistsApr 22-30: 2.5% of 64458 checklistsMay 1-7: 7.8% of 60998 checklistsMay 8-14: 9.9% of 72091 checklistsMay 15-21: 12% of 59058 checklistsMay 22-31: 11% of 64724 checklistsJun 1-7: 11% of 35990 checklistsJun 8-14: 11% of 32595 checklistsJun 15-21: 11% of 30017 checklistsJun 22-30: 9.9% of 33988 checklistsJul 1-7: 9.9% of 28708 checklistsJul 8-14: 9.9% of 25175 checklistsJul 15-21: 10% of 24084 checklistsJul 22-31: 11% of 33522 checklistsAug 1-7: 11% of 25098 checklistsAug 8-14: 11% of 24353 checklistsAug 15-21: 9.6% of 25059 checklistsAug 22-31: 8.6% of 37489 checklistsSep 1-7: 6.8% of 28410 checklistsSep 8-14: 5.6% of 27887 checklistsSep 15-21: 4.9% of 26614 checklistsSep 22-30: 4.4% of 32557 checklistsOct 1-7: 3.7% of 25844 checklistsOct 8-14: 0.9% of 27741 checklistsOct 15-21: 0.3% of 24693 checklistsOct 22-31: 0.1% of 32460 checklistsNov 1-7: 0% of 23660 checklistsNov 8-14: 0% of 21542 checklistsNov 15-21: 0% of 19922 checklistsNov 22-30: 0% of 25069 checklistsDec 1-7: 0% of 18272 checklistsDec 8-14: 0% of 18961 checklistsDec 15-21: 0% of 24171 checklistsDec 22-31: 0% of 30908 checklistsJanFebMarAprMayJunJulAugSepOctNovDec
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 Michigan 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
Second week of November

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.

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Where in Michigan

Best counties

Share of checklists at the peak
  1. Branch CountyBest the second week of August · 23 checklists that week, 2,279 in all34%
  2. Wayne CountyBest late May · 1942 checklists that week, 68,343 in all27%
  3. Oakland CountyBest the second week of August · 1552 checklists that week, 111,342 in all23%
  4. Washtenaw CountyBest early August · 1838 checklists that week, 145,231 in all23%
  5. Saginaw CountyBest mid May · 297 checklists that week, 8,573 in all22%
  6. Genesee CountyBest the second week of June · 603 checklists that week, 29,698 in all21%

Best spots

Share of checklists at the peak
  1. Thurston Nature AreaWashtenaw County, best mid July · 39 checklists that week, 1,608 in all85%
  2. Genessee Recreation AreaGenesee County, best late July · 28 checklists that week, 392 in all78%
  3. Frog Island ParkWashtenaw County, best early May · 37 checklists that week, 144 in all78%
  4. Flushing Township ParkGenesee County, best mid August · 27 checklists that week, 1,247 in all72%
  5. Waterworks ParkWashtenaw County, best the second week of May · 34 checklists that week, 1,330 in all63%

Busy spots report more of everything; compare the checklist counts before you drive anywhere.

Best time of day

In Michigan, the Chimney Swift is most often listed on checklists started between 6 and 8 pm (9.5% of those checklists).

0%5%10%15%12 am: too few checklists (712) to judge1 am: too few checklists (592) to judge2 am: too few checklists (532) to judge3 am: too few checklists (516) to judge4 am: too few checklists (1592) to judge5 am: too few checklists (6849) to judge6 am: 10% of 39298 checklists7 am: 7.0% of 120344 checklists8 am: 4.8% of 180109 checklists9 am: 4.1% of 171966 checklists10 am: 3.3% of 156332 checklists11 am: 3.0% of 134964 checklists12 pm: 2.8% of 120967 checklists1 pm: 2.8% of 113852 checklists2 pm: 2.7% of 110773 checklists3 pm: 2.9% of 105530 checklists4 pm: 3.2% of 100958 checklists5 pm: 4.8% of 80085 checklists6 pm: 8.1% of 62883 checklists7 pm: 11% of 44912 checklists8 pm: too few checklists (21062) to judge9 pm: too few checklists (5920) to judge10 pm: too few checklists (1629) to judge11 pm: too few checklists (775) to judge12a3a6a9a12p3p6p9p
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
MonthDays 1-78-1415-2122-end
January0%0%0%0%
February0%0%0%0%
March0%0%0%0.1%
April0%0.1%0.2%2.5%
May7.8%9.9%12%11%
June11%11%11%9.9%
July9.9%9.9%10%11%
August11%11%9.6%8.6%
September6.8%5.6%4.9%4.4%
October3.7%0.9%0.3%0.1%
November0%0%0%0%
December0%0%0%0%

Neighboring states

  • Ohio: arrives mid April, in the same week than Michigan
  • Indiana: arrives mid April, in the same week than Michigan
  • Illinois: arrives mid April, in the same week than Michigan
  • Wisconsin: arrives late April, 1 week later than Michigan

Common questions

When do Chimney Swifts arrive in Michigan?
Chimney Swifts reach Michigan in mid April, are common by early May, peak in early August (11% of checklists), and most are gone by the second week of September.
When do Chimney Swifts leave Michigan?
Most Chimney Swifts have left Michigan by the second week of September, when reports fall below half their usual rate. Stragglers are still reported until the second week of October.
When is the best time to see a Chimney Swift in Michigan?
The Chimney Swift is reported most often in early August, on about 11% of Michigan checklists.
Where in Michigan are Chimney Swifts seen most often?
By county, Branch County, Wayne County, and Oakland County have the highest peak reporting rates for the Chimney Swift (counties with at least 200 checklists).