WhenToBird

Nycticorax nycticorax · Ardeidae

When Do Black-crowned Night Herons Arrive in California?

Adult Black-crowned Night-Heron
Photo: jubileej, CC0 1.0 via iNaturalist

The Black-crowned Night Heron is in California all year. It turns up on about 8.6% of checklists at its peak (the second week of August) and on 4.6% in its quietest week (late March).

When to look

PresentAll year
Peak weekAug 8-14the second week of August
Quietest weekMar 22-31late March

Best: the second week of August. Here all year. Peak: on about 8.6% of California checklists.

  1. Janpeak season
  2. Febcommon
  3. Marcommon
  4. Aprcommon
  5. Maypeak season
  6. Junpeak season
  7. Julpeak season
  8. Augpeak season
  9. Seppeak season
  10. Octcommon
  11. Novpeak season
  12. Decpeak season

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

0%5%10%Jan 1-7: 7.5% of 112336 checklistsJan 8-14: 7.1% of 85518 checklistsJan 15-21: 6.8% of 86488 checklistsJan 22-31: 6.6% of 116174 checklistsFeb 1-7: 6.2% of 75171 checklistsFeb 8-14: 5.5% of 84467 checklistsFeb 15-21: 4.9% of 105683 checklistsFeb 22-28: 5.6% of 83396 checklistsMar 1-7: 5.2% of 77470 checklistsMar 8-14: 4.9% of 75180 checklistsMar 15-21: 4.7% of 80770 checklistsMar 22-31: 4.5% of 114116 checklistsApr 1-7: 4.8% of 84057 checklistsApr 8-14: 4.9% of 83692 checklistsApr 15-21: 5.2% of 89242 checklistsApr 22-30: 5.6% of 114289 checklistsMay 1-7: 5.9% of 85728 checklistsMay 8-14: 6.0% of 91984 checklistsMay 15-21: 6.4% of 75478 checklistsMay 22-31: 6.4% of 106250 checklistsJun 1-7: 6.6% of 70051 checklistsJun 8-14: 6.9% of 67485 checklistsJun 15-21: 6.9% of 66269 checklistsJun 22-30: 7.4% of 79172 checklistsJul 1-7: 8.0% of 62877 checklistsJul 8-14: 8.2% of 60328 checklistsJul 15-21: 8.2% of 59705 checklistsJul 22-31: 8.4% of 83796 checklistsAug 1-7: 8.9% of 60215 checklistsAug 8-14: 8.6% of 60172 checklistsAug 15-21: 8.5% of 59877 checklistsAug 22-31: 8.5% of 89107 checklistsSep 1-7: 8.2% of 72000 checklistsSep 8-14: 7.4% of 71228 checklistsSep 15-21: 6.8% of 76808 checklistsSep 22-30: 6.6% of 100204 checklistsOct 1-7: 6.5% of 76571 checklistsOct 8-14: 6.1% of 80874 checklistsOct 15-21: 6.1% of 74581 checklistsOct 22-31: 6.3% of 97498 checklistsNov 1-7: 6.7% of 70851 checklistsNov 8-14: 6.5% of 72431 checklistsNov 15-21: 6.6% of 66767 checklistsNov 22-30: 6.9% of 94737 checklistsDec 1-7: 7.1% of 65393 checklistsDec 8-14: 6.7% of 67449 checklistsDec 15-21: 5.8% of 83421 checklistsDec 22-31: 6.5% 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 all31%
  2. Kings CountyBest late May · 99 checklists that week, 3,688 in all31%
  3. Lake CountyBest the second week of December · 217 checklists that week, 12,989 in all25%
  4. Yolo CountyBest early July · 760 checklists that week, 67,424 in all23%
  5. Orange CountyBest late July · 4960 checklists that week, 244,559 in all20%
  6. Sutter CountyBest late October · 127 checklists that week, 4,996 in all16%

Best spots

Share of checklists at the peak
  1. Palace of Fine ArtsSan Francisco County, best late November · 20 checklists that week, 654 in all100%
  2. Park 5-ASacramento County, best the second week of May · 27 checklists that week, 114 in all100%
  3. Lindo Lake ParkSan Diego County, best early June · 25 checklists that week, 2,191 in all97%
  4. Carr ParkOrange County, best the second week of January · 37 checklists that week, 891 in all97%
  5. Santa Clara RiverVentura County, best the second week of January · 164 checklists that week, 5,820 in all96%
  6. Richardson BayMarin County, best late December · 21 checklists that week, 220 in all96%

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

Best time of day

In California, the Black-crowned Night Heron is most often listed on checklists started between 6 and 8 am (9.2% 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: 9.6% of 186053 checklists7 am: 9.1% of 444086 checklists8 am: 8.1% of 535846 checklists9 am: 6.6% of 486061 checklists10 am: 5.4% of 411130 checklists11 am: 4.7% of 325798 checklists12 pm: 4.5% of 269132 checklists1 pm: 4.7% of 244762 checklists2 pm: 5.1% of 235420 checklists3 pm: 5.5% of 232365 checklists4 pm: 5.9% of 208688 checklists5 pm: 6.5% of 146104 checklists6 pm: 7.4% 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
January7.5%7.1%6.8%6.6%
February6.2%5.5%4.9%5.6%
March5.2%4.9%4.7%4.5%
April4.8%4.9%5.2%5.6%
May5.9%6.0%6.4%6.4%
June6.6%6.9%6.9%7.4%
July8.0%8.2%8.2%8.4%
August8.9%8.6%8.5%8.5%
September8.2%7.4%6.8%6.6%
October6.5%6.1%6.1%6.3%
November6.7%6.5%6.6%6.9%
December7.1%6.7%5.8%6.5%

Neighboring states

  • Nevada: year-round, peaks early December
  • Utah: summer visitor, peaks the second week of May
  • Arizona: year-round, peaks the second week of January
  • Idaho: summer visitor, peaks the second week of August

Common questions

When do Black-crowned Night Herons arrive in California?
The Black-crowned Night Heron is in California all year. It turns up on about 8.6% of checklists at its peak (the second week of August) and on 4.6% in its quietest week (late March).
When do Black-crowned Night Herons leave California?
The Black-crowned Night Heron does not leave California: it is reported all year, from 4.6% of checklists in late March to 8.6% in the second week of August.
When is the best time to see a Black-crowned Night Heron in California?
The Black-crowned Night Heron is reported most often in the second week of August, on about 8.6% of California checklists.
Where in California are Black-crowned Night Herons seen most often?
By county, Colusa County, Kings County, and Lake County have the highest peak reporting rates for the Black-crowned Night Heron (counties with at least 200 checklists).