WhenToBird

Cepphus columba · Alcidae

When Do Pigeon Guillemots Arrive in California?

Adult Pigeon Guillemot
Photo: Jeffrey Lee (he/him/his), CC0 1.0 via iNaturalist

Pigeon Guillemots arrive in California in late March, peak in late July (2.8% of checklists), and most are gone by late August.

When to look

First arrivalsMar 22-31late March
Common byMar 22-31late March
PeakJul 22-31late July
Most gone byAug 22-31late August

Best: late July. First arrivals late March; most are gone by late August. Peak: on about 2.8% of California checklists.

  1. Jannot usually seen
  2. Febnot usually seen
  3. Maruncommon
  4. Aprcommon
  5. Maycommon
  6. Junpeak season
  7. Julpeak season
  8. Augpeak season
  9. Sepuncommon
  10. Octrare
  11. Novnot usually seen
  12. Decnot usually seen

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

0%1%2%3%Jan 1-7: 0.1% of 112336 checklistsJan 8-14: 0.1% of 85518 checklistsJan 15-21: 0.1% of 86488 checklistsJan 22-31: 0.1% of 116174 checklistsFeb 1-7: 0.1% of 75171 checklistsFeb 8-14: 0.1% of 84467 checklistsFeb 15-21: 0.1% of 105683 checklistsFeb 22-28: 0.1% of 83396 checklistsMar 1-7: 0.2% of 77470 checklistsMar 8-14: 0.5% of 75180 checklistsMar 15-21: 0.8% of 80770 checklistsMar 22-31: 1.1% of 114116 checklistsApr 1-7: 1.3% of 84057 checklistsApr 8-14: 1.2% of 83692 checklistsApr 15-21: 1.4% of 89242 checklistsApr 22-30: 1.4% of 114289 checklistsMay 1-7: 1.5% of 85728 checklistsMay 8-14: 1.6% of 91984 checklistsMay 15-21: 1.7% of 75478 checklistsMay 22-31: 1.8% of 106250 checklistsJun 1-7: 1.9% of 70051 checklistsJun 8-14: 1.8% of 67485 checklistsJun 15-21: 2.1% of 66269 checklistsJun 22-30: 2.2% of 79172 checklistsJul 1-7: 2.3% of 62877 checklistsJul 8-14: 2.5% of 60328 checklistsJul 15-21: 2.8% of 59705 checklistsJul 22-31: 2.9% of 83796 checklistsAug 1-7: 2.7% of 60215 checklistsAug 8-14: 2.6% of 60172 checklistsAug 15-21: 1.9% of 59877 checklistsAug 22-31: 1.0% of 89107 checklistsSep 1-7: 0.5% of 72000 checklistsSep 8-14: 0.3% of 71228 checklistsSep 15-21: 0.2% of 76808 checklistsSep 22-30: 0.2% of 100204 checklistsOct 1-7: 0.1% of 76571 checklistsOct 8-14: 0.1% of 80874 checklistsOct 15-21: 0.1% of 74581 checklistsOct 22-31: 0.1% of 97498 checklistsNov 1-7: 0.1% of 70851 checklistsNov 8-14: 0.1% of 72431 checklistsNov 15-21: 0.1% of 66767 checklistsNov 22-30: 0.1% of 94737 checklistsDec 1-7: 0.1% of 65393 checklistsDec 8-14: 0.1% of 67449 checklistsDec 15-21: 0.1% of 83421 checklistsDec 22-31: 0.1% 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.

Embed this map on your site

Where in California

Best counties

Share of checklists at the peak
  1. Del Norte CountyBest early August · 314 checklists that week, 16,363 in all16%
  2. Monterey CountyBest late July · 2950 checklists that week, 132,505 in all15%
  3. Mendocino CountyBest late July · 1193 checklists that week, 47,934 in all15%
  4. San Francisco CountyBest mid July · 2042 checklists that week, 130,018 in all15%
  5. Santa Cruz CountyBest late July · 2888 checklists that week, 140,819 in all11%
  6. Marin CountyBest early June · 2565 checklists that week, 135,728 in all8.3%

Best spots

Share of checklists at the peak
  1. Point AlonesMonterey County, best the second week of July · 22 checklists that week, 816 in all98%
  2. Santa Cruz AnchorageSanta Cruz County, best late May · 25 checklists that week, 1,447 in all97%
  3. Quarry CoveSan Luis Obispo County, best late July · 21 checklists that week, 968 in all96%
  4. Wilder Ranch State ParkSanta Cruz County, best early July · 35 checklists that week, 1,824 in all96%
  5. Seal Rocks Beach (Lobos Rock)San Francisco County, best late July · 59 checklists that week, 644 in all96%
  6. Trinidad BayHumboldt County, best late May · 45 checklists that week, 670 in all95%

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

Best time of day

In California, the Pigeon Guillemot is most often listed on checklists started between 10 am and 12 pm (1.0% of those checklists).

0%0.5%1%1.5%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: 1.1% of 186053 checklists7 am: 0.8% of 444086 checklists8 am: 0.8% of 535846 checklists9 am: 0.9% of 486061 checklists10 am: 1.0% of 411130 checklists11 am: 1.0% of 325798 checklists12 pm: 0.9% of 269132 checklists1 pm: 0.8% of 244762 checklists2 pm: 0.7% of 235420 checklists3 pm: 0.6% of 232365 checklists4 pm: 0.6% of 208688 checklists5 pm: 0.7% of 146104 checklists6 pm: 0.7% 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
January0.1%0.1%0.1%0.1%
February0.1%0.1%0.1%0.1%
March0.2%0.5%0.8%1.1%
April1.3%1.2%1.4%1.4%
May1.5%1.6%1.7%1.8%
June1.9%1.8%2.1%2.2%
July2.3%2.5%2.8%2.9%
August2.7%2.6%1.9%1.0%
September0.5%0.3%0.2%0.2%
October0.1%0.1%0.1%0.1%
November0.1%0.1%0.1%0.1%
December0.1%0.1%0.1%0.1%

Neighboring states

  • Oregon: arrives the second week of March, 2 weeks earlier than California
  • Washington: year-round, peaks the second week of August
  • Alaska: arrives mid November, 17 weeks earlier than California

Common questions

When do Pigeon Guillemots arrive in California?
Pigeon Guillemots arrive in California in late March, peak in late July (2.8% of checklists), and most are gone by late August.
When do Pigeon Guillemots leave California?
Most Pigeon Guillemots have left California by late August, when reports fall below half their usual rate.
When is the best time to see a Pigeon Guillemot in California?
The Pigeon Guillemot is reported most often in late July, on about 2.8% of California checklists.
Where in California are Pigeon Guillemots seen most often?
By county, Del Norte County, Monterey County, and Mendocino County have the highest peak reporting rates for the Pigeon Guillemot (counties with at least 200 checklists).