Green-winged Teals are winter birds in Illinois: the first arrive in early February, they are common by mid February, peak in mid March (7.9% of checklists), and most are gone by late April.
When to look
First arrivalsFeb 1-7early February
Common byFeb 15-21mid February
PeakMar 15-21mid March
Most gone byApr 22-30late April
Best: mid March. First arrivals early February; most are gone by late April. Peak: on about 7.9% of Illinois checklists.
Janrare
Febcommon
Marpeak season
Aprpeak season
Mayuncommon
Junnot usually seen
Julnot usually seen
Auguncommon
Sepuncommon
Octpeak season
Novpeak season
Decuncommon
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 Illinois 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.
McGinnis SloughCook County, best late October · 72 checklists that week, 1,925 in all72%
Busy spots report more of everything; compare the checklist counts before you drive anywhere.
Best time of day
In Illinois, the Green-winged Teal is most often listed on checklists started between 12 and 2 pm (2.9% 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
0.9%
0.7%
0.7%
0.8%
February
1.1%
1.2%
1.6%
3.4%
March
5.7%
7.6%
8.0%
8.1%
April
6.6%
6.2%
4.7%
2.6%
May
0.8%
0.3%
0.3%
0.2%
June
0.2%
0.2%
0.2%
0.1%
July
0.2%
0.1%
0.2%
0.2%
August
0.4%
0.5%
1.1%
1.8%
September
2.1%
2.1%
2.1%
3.0%
October
3.9%
4.7%
5.8%
6.3%
November
6.4%
5.6%
4.8%
3.5%
December
2.4%
1.6%
1.3%
1.0%
Neighboring states
Indiana: arrives late August, 21 weeks earlier than Illinois
Wisconsin: arrives late February, 3 weeks later than Illinois
Michigan: arrives late February, 3 weeks later than Illinois
Iowa: arrives the second week of February, 1 week later than Illinois
Common questions
When do Green-winged Teals arrive in Illinois?
Green-winged Teals are winter birds in Illinois: the first arrive in early February, they are common by mid February, peak in mid March (7.9% of checklists), and most are gone by late April.
When do Green-winged Teals leave Illinois?
Most Green-winged Teals have left Illinois by late April, when reports fall below half their usual rate. Stragglers are still reported until early May.
When is the best time to see a Green-winged Teal in Illinois?
The Green-winged Teal is reported most often in mid March, on about 7.9% of Illinois checklists.
Where in Illinois are Green-winged Teals seen most often?
By county, Wayne County, Putnam County, and Pulaski County have the highest peak reporting rates for the Green-winged Teal (counties with at least 200 checklists).