WhenToBird

Larus delawarensis · Laridae

When Do Ring-billed Gulls Arrive in California?

Adult Ring-billed Gull
Photo: Isaac Krone, CC BY 4.0 via iNaturalist

Ring-billed Gulls are winter birds in California: the first arrive in the second week of July, they are common by early August, peak in the second week of January (15% of checklists), and most are gone by early April.

When to look

First arrivalsJul 8-14the second week of July
Common byAug 1-7early August
PeakJan 8-14the second week of January
Most gone byApr 1-7early April

Best: the second week of January. First arrivals the second week of July; most are gone by early April. Peak: on about 15% of California checklists.

  1. Janpeak season
  2. Febpeak season
  3. Marpeak season
  4. Apruncommon
  5. Mayuncommon
  6. Junrare
  7. Juluncommon
  8. Augcommon
  9. Sepuncommon
  10. Octcommon
  11. Novpeak season
  12. Decpeak season

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

0%5%10%15%20%Jan 1-7: 15% of 112336 checklistsJan 8-14: 14% of 85518 checklistsJan 15-21: 14% of 86488 checklistsJan 22-31: 14% of 116174 checklistsFeb 1-7: 14% of 75171 checklistsFeb 8-14: 12% of 84467 checklistsFeb 15-21: 11% of 105683 checklistsFeb 22-28: 13% of 83396 checklistsMar 1-7: 12% of 77470 checklistsMar 8-14: 10% of 75180 checklistsMar 15-21: 8.4% of 80770 checklistsMar 22-31: 6.4% of 114116 checklistsApr 1-7: 5.4% of 84057 checklistsApr 8-14: 4.5% of 83692 checklistsApr 15-21: 4.1% of 89242 checklistsApr 22-30: 3.9% of 114289 checklistsMay 1-7: 3.3% of 85728 checklistsMay 8-14: 2.6% of 91984 checklistsMay 15-21: 2.2% of 75478 checklistsMay 22-31: 1.8% of 106250 checklistsJun 1-7: 1.6% of 70051 checklistsJun 8-14: 1.5% of 67485 checklistsJun 15-21: 1.5% of 66269 checklistsJun 22-30: 1.8% of 79172 checklistsJul 1-7: 2.2% of 62877 checklistsJul 8-14: 2.6% of 60328 checklistsJul 15-21: 3.6% of 59705 checklistsJul 22-31: 4.6% of 83796 checklistsAug 1-7: 5.2% of 60215 checklistsAug 8-14: 6.0% of 60172 checklistsAug 15-21: 5.9% of 59877 checklistsAug 22-31: 5.9% of 89107 checklistsSep 1-7: 5.5% of 72000 checklistsSep 8-14: 5.1% of 71228 checklistsSep 15-21: 4.8% of 76808 checklistsSep 22-30: 5.0% of 100204 checklistsOct 1-7: 5.4% of 76571 checklistsOct 8-14: 5.6% of 80874 checklistsOct 15-21: 6.2% of 74581 checklistsOct 22-31: 7.2% of 97498 checklistsNov 1-7: 8.5% of 70851 checklistsNov 8-14: 9.7% of 72431 checklistsNov 15-21: 11% of 66767 checklistsNov 22-30: 13% of 94737 checklistsDec 1-7: 14% of 65393 checklistsDec 8-14: 14% of 67449 checklistsDec 15-21: 12% of 83421 checklistsDec 22-31: 14% 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. Imperial CountyBest early September · 387 checklists that week, 24,551 in all39%
  2. Modoc CountyBest the second week of April · 66 checklists that week, 6,138 in all28%
  3. Colusa CountyBest early March · 134 checklists that week, 7,653 in all28%
  4. Kings CountyBest mid February · 88 checklists that week, 3,688 in all28%
  5. Orange CountyBest the second week of January · 5807 checklists that week, 244,559 in all27%
  6. Napa CountyBest the second week of August · 283 checklists that week, 18,976 in all26%

Best spots

Share of checklists at the peak
  1. Lake Elsinore State Recreation Area (Warm Springs Valley)Riverside County, best late December · 23 checklists that week, 278 in all97%
  2. Talbert MarshOrange County, best early March · 23 checklists that week, 476 in all95%
  3. Oroville Wildlife AreaButte County, best mid September · 25 checklists that week, 807 in all95%
  4. Greenhorn ParkSiskiyou County, best early May · 22 checklists that week, 680 in all94%
  5. Carl Thornton ParkOrange County, best mid December · 22 checklists that week, 817 in all94%

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

Best time of day

In California, the Ring-billed Gull is most often listed on checklists started between 1 and 3 pm (9.6% of those checklists).

0%5%10%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: 5.8% of 186053 checklists7 am: 7.7% of 444086 checklists8 am: 7.7% of 535846 checklists9 am: 7.8% of 486061 checklists10 am: 8.1% of 411130 checklists11 am: 8.5% of 325798 checklists12 pm: 8.9% of 269132 checklists1 pm: 9.7% of 244762 checklists2 pm: 9.5% of 235420 checklists3 pm: 9.0% of 232365 checklists4 pm: 6.8% of 208688 checklists5 pm: 4.5% of 146104 checklists6 pm: 3.3% 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
January15%14%14%14%
February14%12%11%13%
March12%10%8.4%6.4%
April5.4%4.5%4.1%3.9%
May3.3%2.6%2.2%1.8%
June1.6%1.5%1.5%1.8%
July2.2%2.6%3.6%4.6%
August5.2%6.0%5.9%5.9%
September5.5%5.1%4.8%5.0%
October5.4%5.6%6.2%7.2%
November8.5%9.7%11%13%
December14%14%12%14%

Neighboring states

  • Nevada: arrives early July, 1 week earlier than California
  • Utah: arrives late August, 6 weeks later than California
  • Arizona: arrives mid September, 9 weeks later than California
  • Oregon: arrives early July, 1 week earlier than California

Common questions

When do Ring-billed Gulls arrive in California?
Ring-billed Gulls are winter birds in California: the first arrive in the second week of July, they are common by early August, peak in the second week of January (15% of checklists), and most are gone by early April.
When do Ring-billed Gulls leave California?
Most Ring-billed Gulls have left California by early April, when reports fall below half their usual rate. Stragglers are still reported until mid May.
When is the best time to see a Ring-billed Gull in California?
The Ring-billed Gull is reported most often in the second week of January, on about 15% of California checklists.
Where in California are Ring-billed Gulls seen most often?
By county, Imperial County, Modoc County, and Colusa County have the highest peak reporting rates for the Ring-billed Gull (counties with at least 200 checklists).