When do grackles and blackbirds leave Iowa?

Most Red-winged Blackbirds have left Iowa by late October, when reports fall below half their usual rate. Stragglers are still reported until mid November.

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

The Red-winged Blackbird is reported most often in mid June, on about 65% of Iowa checklists.

Which grackles and blackbirds are in Iowa?

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

8 blackbird species in Iowa

When Do Grackles and blackbirds Arrive in Iowa?

Photo: infiniteuniverse, CC0 1.0 via iNaturalist

Red-winged Blackbirds, Brown-headed Cowbirds, and Common Grackles are the grackles and blackbirds you are most likely to see in Iowa. Red-winged Blackbirds reach Iowa in mid February, are common by early March, peak in mid June (65% of checklists), and most are gone by late October.

When to look

First arrivalsFeb 15-21mid February

Common byMar 1-7early March

PeakJun 15-21mid June

Most gone byOct 22-31late October

Best: mid June. First arrivals mid February; most are gone by late October. Peak: on about 65% of Iowa checklists.

Jannot usually seen
Febuncommon
Marpeak season
Aprpeak season
Maypeak season
Junpeak season
Julpeak season
Augcommon
Sepuncommon
Octcommon
Novuncommon
Decrare

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

Grackles and blackbirds in Iowa, species by species

Species	First arrivals	Common by	Peak	Most gone by	Peak %
Red-winged Blackbird	Feb 15-21	Mar 1-7	Jun 15-21	Oct 22-31	65%
Brown-headed Cowbird	Mar 8-14	Apr 1-7	May 8-14	Jul 15-21	46%
Common Grackle	Feb 22-28	Mar 8-14	Jun 8-14	Jul 22-31	36%
Eastern Meadowlark	Mar 1-7	Mar 15-21	Apr 15-21	Jul 22-31	18%
Bobolink	May 1-7	May 1-7	Jun 1-7	Jul 8-14	5.8%
Rusty Blackbird	Feb 22-28	Feb 22-28	Mar 22-31	Apr 22-30	4.0%
Yellow-headed Blackbird	Apr 8-14	Apr 8-14	May 22-31	Aug 1-7	3.1%
Western Meadowlark	Mar 1-7	Mar 1-7	Jun 8-14	Aug 8-14	2.2%

Red-winged Blackbird
Brown-headed Cowbird
Common Grackle
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 Iowa 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 Iowa

Best counties for Red-winged Blackbird

Share of checklists at the peak

Louisa CountyBest the second week of July · 15 checklists that week, 1,639 in all94%
Howard CountyBest late May · 44 checklists that week, 334 in all93%
Clarke CountyBest late March · 16 checklists that week, 459 in all90%
Ringgold CountyBest mid March · 17 checklists that week, 1,141 in all89%
Winnebago CountyBest the second week of July · 14 checklists that week, 596 in all89%
Union CountyBest mid June · 17 checklists that week, 1,133 in all86%

Common questions

When do grackles and blackbirds arrive in Iowa?: Red-winged Blackbirds reach Iowa in mid February, are common by early March, peak in mid June (65% of checklists), and most are gone by late October.
When do grackles and blackbirds leave Iowa?: Most Red-winged Blackbirds have left Iowa by late October, when reports fall below half their usual rate. Stragglers are still reported until mid November.
When is the best time to see grackles and blackbirds in Iowa?: The Red-winged Blackbird is reported most often in mid June, on about 65% of Iowa checklists.
Which grackles and blackbirds are in Iowa?: Red-winged Blackbird, Brown-headed Cowbird, Common Grackle, Eastern Meadowlark, Bobolink, Rusty Blackbird, Yellow-headed Blackbird, and Western Meadowlark are reported regularly; the Red-winged Blackbird is the most common.