Tricolored Herons reach Delaware in early July, are common by mid July, peak in the second week of August (4.4% of checklists), and most are gone by the second week of October.
When to look
First arrivalsJul 1-7early July
Common byJul 15-21mid July
PeakAug 8-14the second week of August
Most gone byOct 8-14the second week of October
Best: the second week of August. First arrivals early July; most are gone by the second week of October. Peak: on about 4.4% of Delaware checklists.
Janrare
Febrare
Marrare
Aprrare
Mayuncommon
Jununcommon
Julcommon
Augpeak season
Sepcommon
Octuncommon
Novrare
Decrare
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.
Rehoboth FlatsSussex County, best the second week of August · 47 checklists that week, 2,369 in all23%
Shearness PoolKent County, best the second week of August · 91 checklists that week, 2,800 in all22%
Wolfpit MarshSussex County, best late July · 26 checklists that week, 425 in all21%
Busy spots report more of everything; compare the checklist counts before you drive anywhere.
Best time of day
In Delaware, the Tricolored Heron is most often listed on checklists started between 5 and 7 pm (1.6% 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
0.4%
0.4%
0.4%
0.3%
February
0.4%
0.2%
0.1%
0.3%
March
0.3%
0.4%
0.4%
0.3%
April
0.3%
0.6%
0.5%
0.5%
May
0.4%
0.8%
0.6%
0.8%
June
0.5%
0.6%
0.9%
1.0%
July
1.0%
1.0%
1.5%
3.0%
August
4.7%
4.3%
4.2%
3.8%
September
3.2%
2.3%
2.4%
1.5%
October
2.2%
1.3%
1.1%
0.8%
November
0.3%
0.2%
0.1%
0.1%
December
0.1%
0.1%
0.1%
0.2%
Neighboring states
Maryland: arrives late May, 5 weeks earlier than Delaware
New Jersey: arrives the second week of April, 11 weeks earlier than Delaware
Virginia: arrives the second week of April, 11 weeks earlier than Delaware
North Carolina: arrives mid March, 14 weeks earlier than Delaware
Common questions
When do Tricolored Herons arrive in Delaware?
Tricolored Herons reach Delaware in early July, are common by mid July, peak in the second week of August (4.4% of checklists), and most are gone by the second week of October.
When do Tricolored Herons leave Delaware?
Most Tricolored Herons have left Delaware by the second week of October, when reports fall below half their usual rate. Stragglers are still reported until mid October.
When is the best time to see a Tricolored Heron in Delaware?
The Tricolored Heron is reported most often in the second week of August, on about 4.4% of Delaware checklists.
Where in Delaware are Tricolored Herons seen most often?
By county, Kent County, Sussex County, and New Castle County have the highest peak reporting rates for the Tricolored Heron (counties with at least 200 checklists).