Ruddy Ducks are winter birds in Delaware: the first arrive in early October, they are common by mid October, peak in mid November (6.0% of checklists), and most are gone by early April.
When to look
First arrivalsOct 1-7early October
Common byOct 15-21mid October
PeakNov 15-21mid November
Most gone byApr 1-7early April
Best: mid November. First arrivals early October; most are gone by early April. Peak: on about 6.0% of Delaware checklists.
Janpeak season
Febpeak season
Marcommon
Apruncommon
Mayrare
Junrare
Julrare
Augrare
Seprare
Octcommon
Novpeak season
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 Delaware 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.
Busy spots report more of everything; compare the checklist counts before you drive anywhere.
Best time of day
In Delaware, the Ruddy Duck is most often listed on checklists started between 1 and 3 pm (3.4% 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
4.6%
5.2%
4.4%
6.4%
February
5.1%
3.7%
2.6%
3.7%
March
3.9%
3.7%
2.7%
2.8%
April
2.2%
1.9%
1.3%
0.9%
May
0.7%
0.9%
0.8%
0.8%
June
0.4%
0.7%
0.6%
0.2%
July
0.4%
0.6%
0.3%
0.5%
August
0.2%
0.3%
0.2%
0.1%
September
0.2%
0.1%
0.1%
0.4%
October
1.0%
2.4%
2.8%
4.0%
November
5.1%
6.5%
6.0%
5.7%
December
5.9%
5.4%
5.5%
4.3%
Neighboring states
Maryland: arrives the second week of October, 1 week later than Delaware
New Jersey: arrives early October, in the same week than Delaware
District of Columbia: arrives the second week of October, 1 week later than Delaware
Pennsylvania: arrives the second week of October, 1 week later than Delaware
Common questions
When do Ruddy Ducks arrive in Delaware?
Ruddy Ducks are winter birds in Delaware: the first arrive in early October, they are common by mid October, peak in mid November (6.0% of checklists), and most are gone by early April.
When do Ruddy Ducks leave Delaware?
Most Ruddy Ducks have left Delaware by early April, when reports fall below half their usual rate. Stragglers are still reported until mid April.
When is the best time to see a Ruddy Duck in Delaware?
The Ruddy Duck is reported most often in mid November, on about 6.0% of Delaware checklists.
Where in Delaware are Ruddy Ducks seen most often?
By county, Kent County, Sussex County, and New Castle County have the highest peak reporting rates for the Ruddy Duck (counties with at least 200 checklists).