Hooded Mergansers are winter birds in Oklahoma: the first arrive in late October, they are common by early November, peak in the second week of January (9.1% of checklists), and most are gone by early March.
When to look
First arrivalsOct 22-31late October
Common byNov 1-7early November
PeakJan 8-14the second week of January
Most gone byMar 1-7early March
Best: the second week of January. First arrivals late October; most are gone by early March. Peak: on about 9.1% of Oklahoma checklists.
Janpeak season
Febcommon
Maruncommon
Aprrare
Mayrare
Junrare
Julnot usually seen
Augnot usually seen
Sepnot usually seen
Octuncommon
Novcommon
Decpeak season
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 Oklahoma 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.
Lake Hefner (north)Oklahoma County, best the second week of January · 21 checklists that week, 276 in all44%
Lynn Lane ReservoirTulsa County, best the second week of January · 31 checklists that week, 372 in all43%
CLO LandsPayne County, best the second week of January · 41 checklists that week, 1,208 in all42%
Busy spots report more of everything; compare the checklist counts before you drive anywhere.
Best time of day
In Oklahoma, the Hooded Merganser is most often listed on checklists started between 2 and 4 pm (3.5% 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
8.9%
9.7%
9.0%
5.6%
February
5.9%
3.9%
2.9%
4.7%
March
2.4%
2.5%
2.0%
1.5%
April
0.9%
0.8%
0.3%
0.3%
May
0.3%
0.3%
0.4%
0.6%
June
0.3%
0.3%
0.2%
0.1%
July
0.1%
0.1%
0.2%
0.1%
August
0.1%
0.1%
0.1%
0.1%
September
0.2%
0.2%
0.1%
0.2%
October
0.1%
0.1%
0.2%
1.3%
November
4.4%
5.4%
5.5%
6.3%
December
5.6%
6.4%
6.3%
6.7%
Neighboring states
Kansas: arrives late October, in the same week than Oklahoma
Arkansas: arrives early November, 1 week later than Oklahoma
Missouri: arrives late October, in the same week than Oklahoma
Nebraska: arrives mid October, 1 week earlier than Oklahoma
Common questions
When do Hooded Mergansers arrive in Oklahoma?
Hooded Mergansers are winter birds in Oklahoma: the first arrive in late October, they are common by early November, peak in the second week of January (9.1% of checklists), and most are gone by early March.
When do Hooded Mergansers leave Oklahoma?
Most Hooded Mergansers have left Oklahoma by early March, when reports fall below half their usual rate. Stragglers are still reported until early April.
When is the best time to see a Hooded Merganser in Oklahoma?
The Hooded Merganser is reported most often in the second week of January, on about 9.1% of Oklahoma checklists.
Where in Oklahoma are Hooded Mergansers seen most often?
By county, Greer County, Noble County, and Roger Mills County have the highest peak reporting rates for the Hooded Merganser (counties with at least 200 checklists).