WhenToBird

Haematopus bachmani · Haematopodidae

When Do Black Oystercatchers Arrive in Alaska?

Adult Black Oystercatcher
Photo: Mara Christensen, CC BY 4.0 via iNaturalist

Black Oystercatchers arrive in Alaska in early November, peak in late July (3.1% of checklists), and most are gone by mid September.

When to look

First arrivalsNov 1-7early November
Common byNov 1-7early November
PeakJul 22-31late July
Most gone bySep 15-21mid September

Best: late July. First arrivals early November; most are gone by mid September. Peak: on about 3.1% of Alaska checklists.

  1. Januncommon
  2. Febcommon
  3. Marpeak season
  4. Aprpeak season
  5. Maypeak season
  6. Juncommon
  7. Julpeak season
  8. Augpeak season
  9. Sepcommon
  10. Octuncommon
  11. Novuncommon
  12. Deccommon

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

0%1%2%3%4%Jan 1-7: 0.9% of 3788 checklistsJan 8-14: 1.4% of 2852 checklistsJan 15-21: 1.2% of 2810 checklistsJan 22-31: 0.9% of 3629 checklistsFeb 1-7: 1.7% of 2519 checklistsFeb 8-14: 1.5% of 2927 checklistsFeb 15-21: 1.7% of 3743 checklistsFeb 22-28: 1.5% of 2846 checklistsMar 1-7: 1.9% of 2904 checklistsMar 8-14: 1.7% of 3073 checklistsMar 15-21: 2.3% of 3359 checklistsMar 22-31: 2.5% of 5855 checklistsApr 1-7: 2.6% of 4329 checklistsApr 8-14: 2.9% of 4949 checklistsApr 15-21: 2.7% of 7114 checklistsApr 22-30: 2.6% of 10916 checklistsMay 1-7: 3.2% of 11827 checklistsMay 8-14: 2.9% of 14115 checklistsMay 15-21: 3.0% of 12152 checklistsMay 22-31: 2.1% of 19919 checklistsJun 1-7: 1.5% of 15816 checklistsJun 8-14: 1.6% of 17194 checklistsJun 15-21: 1.6% of 15943 checklistsJun 22-30: 1.9% of 16192 checklistsJul 1-7: 2.5% of 9815 checklistsJul 8-14: 2.6% of 8263 checklistsJul 15-21: 3.4% of 7081 checklistsJul 22-31: 3.3% of 9434 checklistsAug 1-7: 2.6% of 6380 checklistsAug 8-14: 2.5% of 6258 checklistsAug 15-21: 2.5% of 6114 checklistsAug 22-31: 1.6% of 8189 checklistsSep 1-7: 1.6% of 5848 checklistsSep 8-14: 1.1% of 4853 checklistsSep 15-21: 0.7% of 4415 checklistsSep 22-30: 1.0% of 5086 checklistsOct 1-7: 0.8% of 3576 checklistsOct 8-14: 0.5% of 4212 checklistsOct 15-21: 0.9% of 3339 checklistsOct 22-31: 0.7% of 4169 checklistsNov 1-7: 0.8% of 2844 checklistsNov 8-14: 1.3% of 2753 checklistsNov 15-21: 1.2% of 2291 checklistsNov 22-30: 1.0% of 3066 checklistsDec 1-7: 1.3% of 2199 checklistsDec 8-14: 1.3% of 2472 checklistsDec 15-21: 1.7% of 3071 checklistsDec 22-31: 1.5% of 3442 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 Alaska 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 Alaska

Best counties

Share of checklists at the peak
  1. Kodiak Island BoroughBest mid July · 192 checklists that week, 11,483 in all32%
  2. Aleutians East BoroughBest the second week of March · 20 checklists that week, 1,634 in all29%
  3. Chugach Census AreaBest mid June · 176 checklists that week, 7,540 in all27%
  4. Aleutians West Census AreaBest the second week of November · 16 checklists that week, 6,087 in all18%
  5. Hoonah-Angoon Census AreaBest early July · 312 checklists that week, 8,159 in all10%
  6. Haines BoroughBest early May · 23 checklists that week, 1,690 in all8.6%

Best spots

Share of checklists at the peak
  1. OrcaChugach Census Area, best early May · 30 checklists that week, 119 in all74%
  2. Middleton IslandChugach Census Area, best early May · 21 checklists that week, 269 in all58%
  3. Lake OrbinKodiak Island Borough, best mid April · 31 checklists that week, 432 in all50%
  4. Fort Abercrombie State Historical ParkKodiak Island Borough, best late May · 22 checklists that week, 709 in all48%
  5. Point LouisaJuneau City and Borough, best late April · 23 checklists that week, 984 in all41%

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

Best time of day

In Alaska, the Black Oystercatcher is most often listed on checklists started between 3 and 5 pm (2.6% of those checklists).

0%1%2%3%12 am: too few checklists (549) to judge1 am: too few checklists (365) to judge2 am: too few checklists (291) to judge3 am: too few checklists (624) to judge4 am: too few checklists (1241) to judge5 am: too few checklists (3532) to judge6 am: 1.7% of 9751 checklists7 am: 1.5% of 17236 checklists8 am: 1.8% of 24936 checklists9 am: 2.1% of 30139 checklists10 am: 2.4% of 30866 checklists11 am: 2.0% of 28207 checklists12 pm: 1.9% of 25650 checklists1 pm: 2.1% of 24144 checklists2 pm: 2.2% of 23323 checklists3 pm: 2.7% of 20763 checklists4 pm: 2.5% of 18245 checklists5 pm: 1.8% of 14895 checklists6 pm: 1.8% of 11707 checklists7 pm: 1.7% of 9365 checklists8 pm: 1.5% of 6934 checklists9 pm: too few checklists (4176) to judge10 pm: too few checklists (2050) to judge11 pm: too few checklists (952) 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
January0.9%1.4%1.2%0.9%
February1.7%1.5%1.7%1.5%
March1.9%1.7%2.3%2.5%
April2.6%2.9%2.7%2.6%
May3.2%2.9%3.0%2.1%
June1.5%1.6%1.6%1.9%
July2.5%2.6%3.4%3.3%
August2.6%2.5%2.5%1.6%
September1.6%1.1%0.7%1.0%
October0.8%0.5%0.9%0.7%
November0.8%1.3%1.2%1.0%
December1.3%1.3%1.7%1.5%

Neighboring states

  • Washington: year-round, peaks mid July
  • Oregon: arrives the second week of March, 17 weeks later than Alaska
  • California: year-round, peaks late July

Common questions

When do Black Oystercatchers arrive in Alaska?
Black Oystercatchers arrive in Alaska in early November, peak in late July (3.1% of checklists), and most are gone by mid September.
When do Black Oystercatchers leave Alaska?
Most Black Oystercatchers have left Alaska by mid September, when reports fall below half their usual rate.
When is the best time to see a Black Oystercatcher in Alaska?
The Black Oystercatcher is reported most often in late July, on about 3.1% of Alaska checklists.
Where in Alaska are Black Oystercatchers seen most often?
By county, Kodiak Island Borough, Aleutians East Borough, and Chugach Census Area have the highest peak reporting rates for the Black Oystercatcher (counties with at least 200 checklists).