American Herring Gulls are winter birds in Idaho: they arrive in late September, peak in mid November (2.6% of checklists), and most are gone by mid March.
When to look
First arrivalsSep 22-30late September
Common bySep 22-30late September
PeakNov 15-21mid November
Most gone byMar 15-21mid March
Best: mid November. First arrivals late September; most are gone by mid March. Peak: on about 2.6% of Idaho checklists.
Janpeak season
Febcommon
Marcommon
Apruncommon
Maynot usually seen
Junnot usually seen
Julnot usually seen
Augrare
Sepuncommon
Octpeak season
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 Idaho 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 Idaho, the American Herring Gull is most often listed on checklists started between 12 and 2 pm (1.4% 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
2.3%
1.7%
2.0%
1.9%
February
1.8%
1.4%
1.4%
1.6%
March
1.1%
1.1%
1.1%
0.8%
April
0.5%
0.5%
0.3%
0.2%
May
0.1%
0.1%
0.1%
0.1%
June
0.1%
0.1%
0.1%
0.1%
July
0.1%
0.1%
0.1%
0.1%
August
0.1%
0.1%
0.2%
0.2%
September
0.6%
0.6%
0.6%
1.3%
October
1.0%
1.6%
2.1%
2.5%
November
2.2%
2.5%
2.5%
2.6%
December
2.2%
1.8%
2.4%
1.8%
Neighboring states
Montana: arrives mid September, 1 week earlier than Idaho
Utah: arrives mid October, 3 weeks later than Idaho
Oregon: arrives early October, 1 week later than Idaho
Washington: arrives mid September, 1 week earlier than Idaho
Common questions
When do American Herring Gulls arrive in Idaho?
American Herring Gulls are winter birds in Idaho: they arrive in late September, peak in mid November (2.6% of checklists), and most are gone by mid March.
When do American Herring Gulls leave Idaho?
Most American Herring Gulls have left Idaho by mid March, when reports fall below half their usual rate.
When is the best time to see a American Herring Gull in Idaho?
The American Herring Gull is reported most often in mid November, on about 2.6% of Idaho checklists.
Where in Idaho are American Herring Gulls seen most often?
By county, Jerome County, Owyhee County, and Power County have the highest peak reporting rates for the American Herring Gull (counties with at least 200 checklists).