WhenToBird

Larus smithsonianus · Laridae

When Do American Herring Gulls Arrive in California?

Adult American Herring Gull
Photo: Priya Sandhu, CC BY 4.0 via iNaturalist

American Herring Gulls are winter birds in California: the first arrive in the second week of October, they are common by late October, peak in early December (5.0% of checklists), and most are gone by the second week of March.

When to look

First arrivalsOct 8-14the second week of October
Common byOct 22-31late October
PeakDec 1-7early December
Most gone byMar 8-14the second week of March

Best: early December. First arrivals the second week of October; most are gone by the second week of March. Peak: on about 5.0% of California checklists.

  1. Janpeak season
  2. Febpeak season
  3. Marcommon
  4. Apruncommon
  5. Mayrare
  6. Junnot usually seen
  7. Julnot usually seen
  8. Augnot usually seen
  9. Seprare
  10. Octcommon
  11. Novpeak season
  12. Decpeak season

Darker months: more checklists report it. Outlined: peak month.

0%2%4%6%Jan 1-7: 4.9% of 112336 checklistsJan 8-14: 4.9% of 85518 checklistsJan 15-21: 4.8% of 86488 checklistsJan 22-31: 4.6% of 116174 checklistsFeb 1-7: 4.4% of 75171 checklistsFeb 8-14: 3.6% of 84467 checklistsFeb 15-21: 3.1% of 105683 checklistsFeb 22-28: 3.4% of 83396 checklistsMar 1-7: 3.0% of 77470 checklistsMar 8-14: 2.2% of 75180 checklistsMar 15-21: 1.5% of 80770 checklistsMar 22-31: 1.1% of 114116 checklistsApr 1-7: 0.7% of 84057 checklistsApr 8-14: 0.6% of 83692 checklistsApr 15-21: 0.5% of 89242 checklistsApr 22-30: 0.4% of 114289 checklistsMay 1-7: 0.2% of 85728 checklistsMay 8-14: 0.2% of 91984 checklistsMay 15-21: 0.1% of 75478 checklistsMay 22-31: 0.1% of 106250 checklistsJun 1-7: 0.1% of 70051 checklistsJun 8-14: 0.1% of 67485 checklistsJun 15-21: 0.1% of 66269 checklistsJun 22-30: 0.1% of 79172 checklistsJul 1-7: 0.1% of 62877 checklistsJul 8-14: 0.1% of 60328 checklistsJul 15-21: 0.1% of 59705 checklistsJul 22-31: 0.1% of 83796 checklistsAug 1-7: 0.1% of 60215 checklistsAug 8-14: 0.1% of 60172 checklistsAug 15-21: 0.1% of 59877 checklistsAug 22-31: 0.1% of 89107 checklistsSep 1-7: 0.1% of 72000 checklistsSep 8-14: 0.2% of 71228 checklistsSep 15-21: 0.3% of 76808 checklistsSep 22-30: 0.5% of 100204 checklistsOct 1-7: 0.8% of 76571 checklistsOct 8-14: 1.2% of 80874 checklistsOct 15-21: 1.9% of 74581 checklistsOct 22-31: 2.6% of 97498 checklistsNov 1-7: 3.5% of 70851 checklistsNov 8-14: 3.9% of 72431 checklistsNov 15-21: 4.6% of 66767 checklistsNov 22-30: 4.9% of 94737 checklistsDec 1-7: 5.2% of 65393 checklistsDec 8-14: 4.8% of 67449 checklistsDec 15-21: 4.3% of 83421 checklistsDec 22-31: 4.7% of 124993 checklistsJanFebMarAprMayJunJulAugSepOctNovDec
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 California 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
Second week of November

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.

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Where in California

Best counties

Share of checklists at the peak
  1. Colusa CountyBest late November · 251 checklists that week, 7,653 in all25%
  2. Sutter CountyBest late November · 155 checklists that week, 4,996 in all21%
  3. Sacramento CountyBest the second week of December · 2103 checklists that week, 121,767 in all20%
  4. Del Norte CountyBest mid February · 265 checklists that week, 16,363 in all20%
  5. Kings CountyBest mid January · 81 checklists that week, 3,688 in all19%
  6. Yuba CountyBest late November · 162 checklists that week, 6,013 in all16%

Best spots

Share of checklists at the peak
  1. Redwood CreekHumboldt County, best late January · 24 checklists that week, 406 in all90%
  2. American River ParkwaySacramento County, best the second week of November · 38 checklists that week, 1,855 in all88%
  3. Gazos Creek Fishing AccessSan Mateo County, best late January · 37 checklists that week, 755 in all87%
  4. Maywood ParkLos Angeles County, best the second week of February · 22 checklists that week, 411 in all85%
  5. American River AccessSacramento County, best late November · 20 checklists that week, 345 in all84%

Busy spots report more of everything; compare the checklist counts before you drive anywhere.

Best time of day

In California, the American Herring Gull is most often listed on checklists started between 1 and 3 pm (2.7% of those checklists).

0%1%2%3%12 am: too few checklists (1688) to judge1 am: too few checklists (1451) to judge2 am: too few checklists (1402) to judge3 am: too few checklists (1743) to judge4 am: too few checklists (4647) to judge5 am: too few checklists (32158) to judge6 am: 1.0% of 186053 checklists7 am: 2.0% of 444086 checklists8 am: 1.8% of 535846 checklists9 am: 2.0% of 486061 checklists10 am: 2.1% of 411130 checklists11 am: 2.3% of 325798 checklists12 pm: 2.4% of 269132 checklists1 pm: 2.7% of 244762 checklists2 pm: 2.7% of 235420 checklists3 pm: 2.5% of 232365 checklists4 pm: 1.7% of 208688 checklists5 pm: 0.7% of 146104 checklists6 pm: 0.3% of 96867 checklists7 pm: too few checklists (50942) to judge8 pm: too few checklists (14803) to judge9 pm: too few checklists (5561) to judge10 pm: too few checklists (3546) to judge11 pm: too few checklists (2092) to judge12a3a6a9a12p3p6p9p
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
MonthDays 1-78-1415-2122-end
January4.9%4.9%4.8%4.6%
February4.4%3.6%3.1%3.4%
March3.0%2.2%1.5%1.1%
April0.7%0.6%0.5%0.4%
May0.2%0.2%0.1%0.1%
June0.1%0.1%0.1%0.1%
July0.1%0.1%0.1%0.1%
August0.1%0.1%0.1%0.1%
September0.1%0.2%0.3%0.5%
October0.8%1.2%1.9%2.6%
November3.5%3.9%4.6%4.9%
December5.2%4.8%4.3%4.7%

Neighboring states

  • Nevada: arrives late October, 2 weeks later than California
  • Utah: arrives mid October, 1 week later than California
  • Oregon: arrives early October, 1 week earlier than California
  • Idaho: arrives late September, 2 weeks earlier than California

Common questions

When do American Herring Gulls arrive in California?
American Herring Gulls are winter birds in California: the first arrive in the second week of October, they are common by late October, peak in early December (5.0% of checklists), and most are gone by the second week of March.
When do American Herring Gulls leave California?
Most American Herring Gulls have left California by the second week of March, when reports fall below half their usual rate. Stragglers are still reported until late March.
When is the best time to see a American Herring Gull in California?
The American Herring Gull is reported most often in early December, on about 5.0% of California checklists.
Where in California are American Herring Gulls seen most often?
By county, Colusa County, Sutter County, and Sacramento County have the highest peak reporting rates for the American Herring Gull (counties with at least 200 checklists).