Bonaparte's Gulls are winter birds in Kansas: they arrive in mid October, peak in mid November (6.4% of checklists), and most are gone by the second week of January.
When to look
First arrivalsOct 15-21mid October
Common byOct 15-21mid October
PeakNov 15-21mid November
Most gone byJan 8-14the second week of January
Best: mid November. First arrivals mid October; most are gone by the second week of January. Peak: on about 6.4% of Kansas checklists.
Januncommon
Febrare
Maruncommon
Aprcommon
Mayrare
Junnot usually seen
Julnot usually seen
Augnot usually seen
Sepnot usually seen
Octcommon
Novpeak season
Deccommon
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 Kansas 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 Kansas, the Bonaparte's Gull is most often listed on checklists started between 10 am and 12 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
1.3%
1.3%
0.5%
0.2%
February
0.4%
0.1%
0.2%
0.5%
March
0.4%
0.6%
1.3%
1.9%
April
2.6%
2.5%
3.0%
1.0%
May
0.3%
0.1%
0.1%
0.1%
June
0%
0%
0.1%
0%
July
0%
0%
0%
0.1%
August
0%
0%
0.1%
0.1%
September
0.1%
0.1%
0.1%
0.1%
October
0.4%
0.6%
1.3%
2.6%
November
5.0%
7.7%
6.0%
5.6%
December
4.9%
2.8%
2.1%
1.5%
Neighboring states
Nebraska: arrives early October, 2 weeks earlier than Kansas
Oklahoma: arrives late October, 1 week later than Kansas
Missouri: arrives early October, 2 weeks earlier than Kansas
Arkansas: arrives mid November, 4 weeks later than Kansas
Common questions
When do Bonaparte's Gulls arrive in Kansas?
Bonaparte's Gulls are winter birds in Kansas: they arrive in mid October, peak in mid November (6.4% of checklists), and most are gone by the second week of January.
When do Bonaparte's Gulls leave Kansas?
Most Bonaparte's Gulls have left Kansas by the second week of January, when reports fall below half their usual rate.
When is the best time to see a Bonaparte's Gull in Kansas?
The Bonaparte's Gull is reported most often in mid November, on about 6.4% of Kansas checklists.
Where in Kansas are Bonaparte's Gulls seen most often?
By county, Jefferson County, Osage County, and Miami County have the highest peak reporting rates for the Bonaparte's Gull (counties with at least 200 checklists).