When do grackles and blackbirds leave Wisconsin?

Most Red-winged Blackbirds have left Wisconsin by mid October, when reports fall below half their usual rate. Stragglers are still reported until the second week of November.

When is the best time to see grackles and blackbirds in Wisconsin?

The Red-winged Blackbird is reported most often in early May, on about 67% of Wisconsin checklists.

Which grackles and blackbirds are in Wisconsin?

Red-winged Blackbird, Common Grackle, Brown-headed Cowbird, Eastern Meadowlark, Bobolink, Rusty Blackbird, and Yellow-headed Blackbird are reported regularly; the Red-winged Blackbird is the most common.

7 blackbird species in Wisconsin

When Do Grackles and blackbirds Arrive in Wisconsin?

Photo: infiniteuniverse, CC0 1.0 via iNaturalist

Red-winged Blackbirds, Common Grackles, and Brown-headed Cowbirds are the grackles and blackbirds you are most likely to see in Wisconsin. Red-winged Blackbirds reach Wisconsin in mid February, are common by early March, peak in early May (67% of checklists), and most are gone by mid October.

When to look

First arrivalsFeb 15-21mid February

Common byMar 1-7early March

PeakMay 1-7early May

Most gone byOct 15-21mid October

Best: early May. First arrivals mid February; most are gone by mid October. Peak: on about 67% of Wisconsin checklists.

Jannot usually seen
Febuncommon
Marpeak season
Aprpeak season
Maypeak season
Junpeak season
Julpeak season
Augcommon
Sepuncommon
Octuncommon
Novuncommon
Decnot usually seen

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

Grackles and blackbirds in Wisconsin, species by species

Species	First arrivals	Common by	Peak	Most gone by	Peak %
Red-winged Blackbird	Feb 15-21	Mar 1-7	May 1-7	Oct 15-21	67%
Common Grackle	Feb 22-28	Mar 8-14	May 8-14	Aug 15-21	41%
Brown-headed Cowbird	Mar 8-14	Apr 1-7	May 8-14	Jul 8-14	40%
Eastern Meadowlark	Mar 1-7	Mar 15-21	Jun 8-14	Jul 22-31	8.4%
Bobolink	May 1-7	May 8-14	Jun 8-14	Jul 8-14	7.1%
Rusty Blackbird	Sep 15-21	Sep 15-21	Oct 15-21	Nov 15-21	3.9%
Yellow-headed Blackbird	Apr 15-21	Apr 15-21	Jun 1-7	Aug 15-21	2.5%

Red-winged Blackbird
Common Grackle
Brown-headed Cowbird
Eastern Meadowlark

Share of complete checklists reporting each species, by week (4 per month). Gaps: fewer than 10 checklists that week.

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.

Where in Wisconsin

Best counties for Red-winged Blackbird

Share of checklists at the peak

Winnebago CountyBest mid June · 406 checklists that week, 26,460 in all86%
Dodge CountyBest the second week of June · 1051 checklists that week, 34,980 in all86%
Lafayette CountyBest mid June · 94 checklists that week, 1,911 in all85%
Kewaunee CountyBest late June · 192 checklists that week, 9,747 in all78%
Green CountyBest mid June · 140 checklists that week, 4,387 in all78%
Iowa CountyBest late April · 721 checklists that week, 18,836 in all78%

Common questions

When do grackles and blackbirds arrive in Wisconsin?: Red-winged Blackbirds reach Wisconsin in mid February, are common by early March, peak in early May (67% of checklists), and most are gone by mid October.
When do grackles and blackbirds leave Wisconsin?: Most Red-winged Blackbirds have left Wisconsin by mid October, when reports fall below half their usual rate. Stragglers are still reported until the second week of November.
When is the best time to see grackles and blackbirds in Wisconsin?: The Red-winged Blackbird is reported most often in early May, on about 67% of Wisconsin checklists.
Which grackles and blackbirds are in Wisconsin?: Red-winged Blackbird, Common Grackle, Brown-headed Cowbird, Eastern Meadowlark, Bobolink, Rusty Blackbird, and Yellow-headed Blackbird are reported regularly; the Red-winged Blackbird is the most common.