WhenToBird

Uria aalge · Alcidae

When Do Common Murres Arrive in California?

Adult Common Murre
Photo: Quinn, CC BY-SA 4.0 via iNaturalist

Common Murres reach California in mid January, are common by late April, peak in early August (1.9% of checklists), and most are gone by mid December.

When to look

First arrivalsJan 15-21mid January
Common byApr 22-30late April
PeakAug 1-7early August
Most gone byDec 15-21mid December

Best: early August. First arrivals mid January; most are gone by mid December. Peak: on about 1.9% of California checklists.

  1. Januncommon
  2. Febuncommon
  3. Maruncommon
  4. Apruncommon
  5. Maycommon
  6. Juncommon
  7. Julpeak season
  8. Augpeak season
  9. Sepcommon
  10. Octcommon
  11. Novpeak season
  12. Decpeak season

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

0%0.5%1%1.5%2%Jan 1-7: 0.5% of 112336 checklistsJan 8-14: 0.6% of 85518 checklistsJan 15-21: 0.5% of 86488 checklistsJan 22-31: 0.6% of 116174 checklistsFeb 1-7: 0.6% of 75171 checklistsFeb 8-14: 0.6% of 84467 checklistsFeb 15-21: 0.5% of 105683 checklistsFeb 22-28: 0.6% of 83396 checklistsMar 1-7: 0.6% of 77470 checklistsMar 8-14: 0.7% of 75180 checklistsMar 15-21: 0.7% of 80770 checklistsMar 22-31: 0.7% of 114116 checklistsApr 1-7: 0.6% of 84057 checklistsApr 8-14: 0.6% of 83692 checklistsApr 15-21: 0.7% of 89242 checklistsApr 22-30: 0.7% of 114289 checklistsMay 1-7: 0.8% of 85728 checklistsMay 8-14: 0.7% of 91984 checklistsMay 15-21: 1.0% of 75478 checklistsMay 22-31: 1.0% of 106250 checklistsJun 1-7: 1.0% of 70051 checklistsJun 8-14: 1.0% of 67485 checklistsJun 15-21: 1.2% of 66269 checklistsJun 22-30: 1.4% of 79172 checklistsJul 1-7: 1.6% of 62877 checklistsJul 8-14: 1.7% of 60328 checklistsJul 15-21: 1.8% of 59705 checklistsJul 22-31: 1.9% of 83796 checklistsAug 1-7: 1.7% of 60215 checklistsAug 8-14: 1.9% of 60172 checklistsAug 15-21: 1.6% of 59877 checklistsAug 22-31: 1.4% of 89107 checklistsSep 1-7: 1.4% of 72000 checklistsSep 8-14: 1.2% of 71228 checklistsSep 15-21: 1.0% of 76808 checklistsSep 22-30: 0.9% of 100204 checklistsOct 1-7: 0.9% of 76571 checklistsOct 8-14: 0.8% of 80874 checklistsOct 15-21: 0.8% of 74581 checklistsOct 22-31: 0.8% of 97498 checklistsNov 1-7: 1.7% of 70851 checklistsNov 8-14: 1.6% of 72431 checklistsNov 15-21: 1.8% of 66767 checklistsNov 22-30: 1.7% of 94737 checklistsDec 1-7: 1.7% of 65393 checklistsDec 8-14: 1.6% of 67449 checklistsDec 15-21: 0.6% of 83421 checklistsDec 22-31: 0.6% 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. Monterey CountyBest early December · 2617 checklists that week, 132,505 in all29%
  2. Del Norte CountyBest mid July · 331 checklists that week, 16,363 in all21%
  3. Mendocino CountyBest late July · 1193 checklists that week, 47,934 in all13%
  4. Humboldt CountyBest mid July · 1471 checklists that week, 95,963 in all11%
  5. Marin CountyBest early August · 1988 checklists that week, 135,728 in all8.9%
  6. San Mateo CountyBest the second week of August · 2354 checklists that week, 148,781 in all8.1%

Best spots

Share of checklists at the peak
  1. Devil's Slide TrailSan Mateo County, best early July · 25 checklists that week, 1,267 in all98%
  2. Half Moon BaySan Mateo County, best mid September · 21 checklists that week, 243 in all93%
  3. Mendocino Headlands State ParkMendocino County, best mid July · 26 checklists that week, 532 in all91%
  4. Crespi PondMonterey County, best the second week of December · 710 checklists that week, 7,637 in all90%
  5. Sea Lion CoveMarin County, best the second week of July · 26 checklists that week, 2,445 in all89%

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

Best time of day

In California, the Common Murre is most often listed on checklists started between 6 and 8 am (1.3% 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: 1.4% of 186053 checklists7 am: 1.2% of 444086 checklists8 am: 1.0% of 535846 checklists9 am: 1.0% of 486061 checklists10 am: 1.0% of 411130 checklists11 am: 1.0% of 325798 checklists12 pm: 1.0% of 269132 checklists1 pm: 1.0% of 244762 checklists2 pm: 1.0% of 235420 checklists3 pm: 0.9% of 232365 checklists4 pm: 0.9% of 208688 checklists5 pm: 0.8% 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
January0.5%0.6%0.5%0.6%
February0.6%0.6%0.5%0.6%
March0.6%0.7%0.7%0.7%
April0.6%0.6%0.7%0.7%
May0.8%0.7%1.0%1.0%
June1.0%1.0%1.2%1.4%
July1.6%1.7%1.8%1.9%
August1.7%1.9%1.6%1.4%
September1.4%1.2%1.0%0.9%
October0.9%0.8%0.8%0.8%
November1.7%1.6%1.8%1.7%
December1.7%1.6%0.6%0.6%

Neighboring states

  • Oregon: arrives the second week of April, 11 weeks later than California
  • Washington: arrives mid July, 24 weeks earlier than California
  • Alaska: arrives late April, 13 weeks later than California

Common questions

When do Common Murres arrive in California?
Common Murres reach California in mid January, are common by late April, peak in early August (1.9% of checklists), and most are gone by mid December.
When do Common Murres leave California?
Most Common Murres have left California by mid December, when reports fall below half their usual rate. Stragglers are still reported until late December.
When is the best time to see a Common Murre in California?
The Common Murre is reported most often in early August, on about 1.9% of California checklists.
Where in California are Common Murres seen most often?
By county, Monterey County, Del Norte County, and Mendocino County have the highest peak reporting rates for the Common Murre (counties with at least 200 checklists).