Green-winged Teals reach Montana in early August, are common by the second week of August, peak in mid April (15% of checklists), and most are gone by mid May.
When to look
First arrivalsAug 1-7early August
Common byAug 8-14the second week of August
PeakApr 15-21mid April
Most gone byMay 15-21mid May
Best: mid April. First arrivals early August; most are gone by mid May. Peak: on about 15% of Montana checklists.
Januncommon
Febuncommon
Marcommon
Aprpeak season
Maycommon
Jununcommon
Julrare
Augcommon
Sepcommon
Octcommon
Novcommon
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 Montana 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.
Cottonwood ReservoirPark County, best mid April · 29 checklists that week, 638 in all84%
Big LakeStillwater County, best late April · 24 checklists that week, 239 in all76%
Busy spots report more of everything; compare the checklist counts before you drive anywhere.
Best time of day
In Montana, the Green-winged Teal is most often listed on checklists started between 5 and 7 pm (6.9% 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
3.3%
3.2%
3.6%
3.0%
February
3.2%
2.6%
2.4%
3.3%
March
4.5%
4.5%
6.3%
9.7%
April
13%
15%
16%
15%
May
10%
6.7%
4.4%
3.6%
June
3.1%
3.1%
2.5%
2.5%
July
1.7%
1.6%
1.3%
1.8%
August
3.2%
5.2%
6.9%
7.4%
September
7.6%
7.0%
7.8%
8.7%
October
8.7%
10%
10%
10%
November
10%
8.4%
6.1%
5.1%
December
3.7%
3.1%
3.5%
3.2%
Neighboring states
Idaho: arrives early August, in the same week than Montana
Wyoming: arrives the second week of February, 23 weeks earlier than Montana
Utah: arrives the second week of August, 1 week later than Montana
Washington: arrives early August, in the same week than Montana
Common questions
When do Green-winged Teals arrive in Montana?
Green-winged Teals reach Montana in early August, are common by the second week of August, peak in mid April (15% of checklists), and most are gone by mid May.
When do Green-winged Teals leave Montana?
Most Green-winged Teals have left Montana by mid May, when reports fall below half their usual rate. Stragglers are still reported until late June.
When is the best time to see a Green-winged Teal in Montana?
The Green-winged Teal is reported most often in mid April, on about 15% of Montana checklists.
Where in Montana are Green-winged Teals seen most often?
By county, Deer Lodge County, Silver Bow County, and Rosebud County have the highest peak reporting rates for the Green-winged Teal (counties with at least 200 checklists).