WhenToBird

Setophaga virens · Parulidae

When Do Black-throated Green Warblers Arrive in Michigan?

Adult Black-throated Green Warbler
Photo: Ken Clark, CC BY 4.0 via iNaturalist

Black-throated Green Warblers arrive in Michigan in late April, peak in the second week of May (14% of checklists), and most are gone by early October.

When to look

First arrivalsApr 22-30late April
Common byApr 22-30late April
PeakMay 8-14the second week of May
Most gone byOct 1-7early October

Best: the second week of May. First arrivals late April; most are gone by early October. Peak: on about 14% of Michigan checklists.

  1. Jannot usually seen
  2. Febnot usually seen
  3. Marnot usually seen
  4. Apruncommon
  5. Maypeak season
  6. Juncommon
  7. Juluncommon
  8. Auguncommon
  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%20%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% of 47777 checklistsApr 1-7: 0.1% of 38557 checklistsApr 8-14: 0.1% of 42207 checklistsApr 15-21: 0.1% of 42759 checklistsApr 22-30: 2.1% of 64458 checklistsMay 1-7: 11% of 60998 checklistsMay 8-14: 15% of 72091 checklistsMay 15-21: 15% of 59058 checklistsMay 22-31: 9.2% of 64724 checklistsJun 1-7: 6.2% of 35990 checklistsJun 8-14: 5.9% of 32595 checklistsJun 15-21: 5.4% of 30017 checklistsJun 22-30: 5.2% of 33988 checklistsJul 1-7: 4.7% of 28708 checklistsJul 8-14: 4.3% of 25175 checklistsJul 15-21: 3.4% of 24084 checklistsJul 22-31: 2.2% of 33522 checklistsAug 1-7: 1.6% of 25098 checklistsAug 8-14: 1.8% of 24353 checklistsAug 15-21: 2.4% of 25059 checklistsAug 22-31: 5.1% of 37489 checklistsSep 1-7: 8.5% of 28410 checklistsSep 8-14: 10% of 27887 checklistsSep 15-21: 9.3% of 26614 checklistsSep 22-30: 8.5% of 32557 checklistsOct 1-7: 3.9% of 25844 checklistsOct 8-14: 0.8% of 27741 checklistsOct 15-21: 0.1% 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: 0.1% 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. Keweenaw CountyBest early June · 496 checklists that week, 12,437 in all44%
  2. Ontonagon CountyBest mid June · 110 checklists that week, 3,548 in all44%
  3. Delta CountyBest mid May · 374 checklists that week, 6,537 in all42%
  4. Mackinac CountyBest mid May · 305 checklists that week, 7,988 in all41%
  5. Baraga CountyBest mid May · 231 checklists that week, 3,662 in all37%
  6. Luce CountyBest mid May · 212 checklists that week, 2,575 in all36%

Best spots

Share of checklists at the peak
  1. Bush Bay Nature Preserve-CHI-MACMackinac County, best early June · 22 checklists that week, 113 in all91%
  2. County of Baraga ParkBaraga County, best late May · 70 checklists that week, 177 in all88%
  3. Peninsula PointDelta County, best mid May · 94 checklists that week, 686 in all86%
  4. Hartwick Lake (east)Crawford County, best late May · 38 checklists that week, 264 in all84%
  5. Sleeping Bear Dunes National Lakeshore (southeast)Leelanau County, best late May · 23 checklists that week, 247 in all81%

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

Best time of day

In Michigan, the Black-throated Green Warbler is most often listed on checklists started between 6 and 8 am (7.7% of those checklists).

0%5%10%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: 8.9% of 39298 checklists7 am: 7.3% of 120344 checklists8 am: 5.5% of 180109 checklists9 am: 4.5% of 171966 checklists10 am: 3.7% of 156332 checklists11 am: 3.3% of 134964 checklists12 pm: 2.8% of 120967 checklists1 pm: 2.8% of 113852 checklists2 pm: 2.6% of 110773 checklists3 pm: 2.4% of 105530 checklists4 pm: 2.4% of 100958 checklists5 pm: 2.7% of 80085 checklists6 pm: 2.7% of 62883 checklists7 pm: 1.9% 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%
April0.1%0.1%0.1%2.1%
May11%15%15%9.2%
June6.2%5.9%5.4%5.2%
July4.7%4.3%3.4%2.2%
August1.6%1.8%2.4%5.1%
September8.5%10%9.3%8.5%
October3.9%0.8%0.1%0.1%
November0%0%0%0%
December0%0%0%0.1%

Neighboring states

  • Ohio: arrives mid April, 1 week earlier than Michigan
  • Indiana: arrives late August, 16 weeks later than Michigan
  • Illinois: arrives mid April, 1 week earlier than Michigan
  • Wisconsin: arrives late April, in the same week than Michigan

Common questions

When do Black-throated Green Warblers arrive in Michigan?
Black-throated Green Warblers arrive in Michigan in late April, peak in the second week of May (14% of checklists), and most are gone by early October.
When do Black-throated Green Warblers leave Michigan?
Most Black-throated Green Warblers have left Michigan by early October, 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 Black-throated Green Warbler in Michigan?
The Black-throated Green Warbler is reported most often in the second week of May, on about 14% of Michigan checklists.
Where in Michigan are Black-throated Green Warblers seen most often?
By county, Keweenaw County, Ontonagon County, and Delta County have the highest peak reporting rates for the Black-throated Green Warbler (counties with at least 200 checklists).