WhenToBird

Sula leucogaster · Sulidae

When Do Brown Boobies Arrive in Hawaii?

Adult Brown Booby
Photo: Melanie Gaddy, CC0 1.0 via iNaturalist

The Brown Booby is in Hawaii all year. It turns up on about 5.8% of checklists at its peak (mid February) and on 3.5% in its quietest week (late October).

When to look

PresentAll year
Peak weekFeb 15-21mid February
Quietest weekOct 22-31late October

Best: mid February. Here all year. Peak: on about 5.8% of Hawaii checklists.

  1. Janpeak season
  2. Febpeak season
  3. Marpeak season
  4. Aprpeak season
  5. Maypeak season
  6. Junpeak season
  7. Julcommon
  8. Augpeak season
  9. Sepcommon
  10. Octcommon
  11. Novcommon
  12. Decpeak season

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

0%2%4%6%8%Jan 1-7: 4.3% of 5223 checklistsJan 8-14: 3.7% of 4322 checklistsJan 15-21: 4.5% of 4791 checklistsJan 22-31: 5.1% of 6113 checklistsFeb 1-7: 5.3% of 4916 checklistsFeb 8-14: 6.1% of 4778 checklistsFeb 15-21: 5.1% of 5119 checklistsFeb 22-28: 6.3% of 5246 checklistsMar 1-7: 5.7% of 4356 checklistsMar 8-14: 5.0% of 4127 checklistsMar 15-21: 4.8% of 4584 checklistsMar 22-31: 5.6% of 5941 checklistsApr 1-7: 5.2% of 3596 checklistsApr 8-14: 5.6% of 3301 checklistsApr 15-21: 5.6% of 3268 checklistsApr 22-30: 5.7% of 3732 checklistsMay 1-7: 5.7% of 2628 checklistsMay 8-14: 5.5% of 3151 checklistsMay 15-21: 5.4% of 2566 checklistsMay 22-31: 4.6% of 4054 checklistsJun 1-7: 4.8% of 2703 checklistsJun 8-14: 5.6% of 2731 checklistsJun 15-21: 5.1% of 2826 checklistsJun 22-30: 4.4% of 3671 checklistsJul 1-7: 3.9% of 2692 checklistsJul 8-14: 4.3% of 2734 checklistsJul 15-21: 3.8% of 2412 checklistsJul 22-31: 4.4% of 3581 checklistsAug 1-7: 4.3% of 2426 checklistsAug 8-14: 4.2% of 2669 checklistsAug 15-21: 5.0% of 2605 checklistsAug 22-31: 4.4% of 3159 checklistsSep 1-7: 4.5% of 2502 checklistsSep 8-14: 2.7% of 2975 checklistsSep 15-21: 4.5% of 3090 checklistsSep 22-30: 4.5% of 3424 checklistsOct 1-7: 3.2% of 2897 checklistsOct 8-14: 5.0% of 3420 checklistsOct 15-21: 3.8% of 3802 checklistsOct 22-31: 3.2% of 4531 checklistsNov 1-7: 3.6% of 3215 checklistsNov 8-14: 4.2% of 3704 checklistsNov 15-21: 4.4% of 3216 checklistsNov 22-30: 4.0% of 4153 checklistsDec 1-7: 4.0% of 3627 checklistsDec 8-14: 4.7% of 3710 checklistsDec 15-21: 5.3% of 3731 checklistsDec 22-31: 4.8% of 6597 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 Hawaii 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 Hawaii

Best counties

Share of checklists at the peak
  1. Northwestern Hawaiian Islands CountyBest early June · 13 checklists that week, 404 in all78%
  2. Kauai CountyBest mid August · 520 checklists that week, 32,543 in all13%
  3. Honolulu CountyBest early March · 1121 checklists that week, 47,705 in all9.2%
  4. Maui CountyBest early January · 525 checklists that week, 22,729 in all2.5%
  5. Hawaii CountyBest mid February · 2042 checklists that week, 75,146 in all2.5%

Best spots

Share of checklists at the peak
  1. Kilauea Point National Wildlife RefugeKauai County, best mid November · 41 checklists that week, 2,548 in all73%
  2. Keāhole PointHawaii County, best the second week of February · 36 checklists that week, 1,290 in all68%
  3. Koko Head Regional Park (Hālona Cove)Honolulu County, best early April · 22 checklists that week, 571 in all55%
  4. Makahūʻena PointKauai County, best late March · 23 checklists that week, 387 in all54%
  5. Green IslandNorthwestern Hawaiian Islands County, best late December · 35 checklists that week, 303 in all53%
  6. Kaiwi State Scenic ShorelineHonolulu County, best late May · 20 checklists that week, 469 in all51%

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

Best time of day

In Hawaii, the Brown Booby is most often listed on checklists started between 5 and 7 pm (8.5% of those checklists).

0%5%10%12 am: too few checklists (66) to judge1 am: too few checklists (53) to judge2 am: too few checklists (70) to judge3 am: too few checklists (68) to judge4 am: too few checklists (106) to judge5 am: too few checklists (1548) to judge6 am: 3.0% of 10237 checklists7 am: 3.5% of 17935 checklists8 am: 3.7% of 18565 checklists9 am: 3.8% of 19076 checklists10 am: 5.6% of 18179 checklists11 am: 4.8% of 15530 checklists12 pm: 4.9% of 13069 checklists1 pm: 4.6% of 12798 checklists2 pm: 4.8% of 12698 checklists3 pm: 5.0% of 12213 checklists4 pm: 6.1% of 10921 checklists5 pm: 8.7% of 9437 checklists6 pm: 8.0% of 4360 checklists7 pm: too few checklists (1028) to judge8 pm: too few checklists (316) to judge9 pm: too few checklists (182) to judge10 pm: too few checklists (110) to judge11 pm: too few checklists (50) 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
January4.3%3.7%4.5%5.1%
February5.3%6.1%5.1%6.3%
March5.7%5.0%4.8%5.6%
April5.2%5.6%5.6%5.7%
May5.7%5.5%5.4%4.6%
June4.8%5.6%5.1%4.4%
July3.9%4.3%3.8%4.4%
August4.3%4.2%5.0%4.4%
September4.5%2.7%4.5%4.5%
October3.2%5.0%3.8%3.2%
November3.6%4.2%4.4%4.0%
December4.0%4.7%5.3%4.8%

Common questions

When do Brown Boobies arrive in Hawaii?
The Brown Booby is in Hawaii all year. It turns up on about 5.8% of checklists at its peak (mid February) and on 3.5% in its quietest week (late October).
When do Brown Boobies leave Hawaii?
The Brown Booby does not leave Hawaii: it is reported all year, from 3.5% of checklists in late October to 5.8% in mid February.
When is the best time to see a Brown Booby in Hawaii?
The Brown Booby is reported most often in mid February, on about 5.8% of Hawaii checklists.
Where in Hawaii are Brown Boobies seen most often?
By county, Northwestern Hawaiian Islands County, Kauai County, and Honolulu County have the highest peak reporting rates for the Brown Booby (counties with at least 200 checklists).