WhenToBird

Ardea herodias · Ardeidae

When Do Great Blue Herons Arrive in Washington?

Adult Great Blue Heron
Photo: mostbittern, CC BY 4.0 via iNaturalist

The Great Blue Heron is in Washington all year. It turns up on about 29% of checklists at its peak (early September) and on 16% in its quietest week (mid February).

When to look

PresentAll year
Peak weekSep 1-7early September
Quietest weekFeb 15-21mid February

Best: early September. Here all year. Peak: on about 29% of Washington checklists.

  1. Jancommon
  2. Febcommon
  3. Marcommon
  4. Aprcommon
  5. Maycommon
  6. Juncommon
  7. Julpeak season
  8. Augpeak season
  9. Seppeak season
  10. Octpeak season
  11. Novpeak season
  12. Decpeak season

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

0%10%20%30%Jan 1-7: 19% of 41928 checklistsJan 8-14: 19% of 31152 checklistsJan 15-21: 19% of 31753 checklistsJan 22-31: 19% of 42530 checklistsFeb 1-7: 18% of 29739 checklistsFeb 8-14: 16% of 32746 checklistsFeb 15-21: 16% of 40328 checklistsFeb 22-28: 17% of 28432 checklistsMar 1-7: 18% of 30758 checklistsMar 8-14: 18% of 29368 checklistsMar 15-21: 17% of 32580 checklistsMar 22-31: 17% of 45614 checklistsApr 1-7: 17% of 33997 checklistsApr 8-14: 18% of 34729 checklistsApr 15-21: 19% of 38474 checklistsApr 22-30: 20% of 52185 checklistsMay 1-7: 19% of 44236 checklistsMay 8-14: 19% of 48708 checklistsMay 15-21: 18% of 41742 checklistsMay 22-31: 18% of 57082 checklistsJun 1-7: 17% of 39193 checklistsJun 8-14: 17% of 36042 checklistsJun 15-21: 17% of 34003 checklistsJun 22-30: 18% of 39711 checklistsJul 1-7: 19% of 31949 checklistsJul 8-14: 21% of 29086 checklistsJul 15-21: 21% of 28045 checklistsJul 22-31: 23% of 38275 checklistsAug 1-7: 25% of 28846 checklistsAug 8-14: 26% of 28036 checklistsAug 15-21: 28% of 27614 checklistsAug 22-31: 29% of 40356 checklistsSep 1-7: 29% of 31214 checklistsSep 8-14: 29% of 27795 checklistsSep 15-21: 28% of 29677 checklistsSep 22-30: 28% of 35241 checklistsOct 1-7: 27% of 28605 checklistsOct 8-14: 26% of 28655 checklistsOct 15-21: 26% of 24643 checklistsOct 22-31: 26% of 34874 checklistsNov 1-7: 24% of 25658 checklistsNov 8-14: 24% of 25700 checklistsNov 15-21: 24% of 24331 checklistsNov 22-30: 23% of 32784 checklistsDec 1-7: 21% of 24099 checklistsDec 8-14: 20% of 23339 checklistsDec 15-21: 18% of 27666 checklistsDec 22-31: 19% of 42130 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 Washington 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 Washington

Best counties

Share of checklists at the peak
  1. Skagit CountyBest late August · 2128 checklists that week, 78,154 in all51%
  2. Wahkiakum CountyBest the second week of August · 88 checklists that week, 5,618 in all50%
  3. Cowlitz CountyBest early October · 291 checklists that week, 15,273 in all45%
  4. Clark CountyBest early October · 1064 checklists that week, 53,250 in all42%
  5. Pacific CountyBest the second week of October · 378 checklists that week, 19,516 in all42%
  6. Island CountyBest late August · 1164 checklists that week, 46,092 in all41%

Best spots

Share of checklists at the peak
  1. Foulweather BluffKitsap County, best mid July · 40 checklists that week, 1,222 in all99%
  2. Hiram M. Chittenden LocksKing County, best late June · 30 checklists that week, 1,319 in all98%
  3. Old Fort LakePierce County, best late June · 21 checklists that week, 478 in all97%
  4. Leque IslandSnohomish County, best the second week of May · 55 checklists that week, 2,807 in all97%
  5. Quigley LakeClark County, best early November · 115 checklists that week, 6,702 in all97%
  6. Buckmire SloughClark County, best mid September · 40 checklists that week, 1,347 in all96%

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

Best time of day

In Washington, the Great Blue Heron is most often listed on checklists started between 6 and 8 am (23% of those checklists).

0%10%20%30%12 am: too few checklists (796) to judge1 am: too few checklists (776) to judge2 am: too few checklists (709) to judge3 am: too few checklists (901) to judge4 am: too few checklists (3221) to judge5 am: too few checklists (16576) to judge6 am: 25% of 56744 checklists7 am: 22% of 133294 checklists8 am: 22% of 184196 checklists9 am: 22% of 186303 checklists10 am: 22% of 177063 checklists11 am: 21% of 154936 checklists12 pm: 20% of 138061 checklists1 pm: 21% of 127449 checklists2 pm: 21% of 121511 checklists3 pm: 21% of 107793 checklists4 pm: 19% of 82862 checklists5 pm: 18% of 57183 checklists6 pm: 17% of 39886 checklists7 pm: too few checklists (26969) to judge8 pm: too few checklists (12427) to judge9 pm: too few checklists (3658) to judge10 pm: too few checklists (1500) to judge11 pm: too few checklists (834) 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
January19%19%19%19%
February18%16%16%17%
March18%18%17%17%
April17%18%19%20%
May19%19%18%18%
June17%17%17%18%
July19%21%21%23%
August25%26%28%29%
September29%29%28%28%
October27%26%26%26%
November24%24%24%23%
December21%20%18%19%

Neighboring states

  • Oregon: year-round, peaks early September
  • Idaho: year-round, peaks early September
  • Montana: all year, most in summer, peaks mid August
  • Nevada: all year, most in fall, peaks early September

Common questions

When do Great Blue Herons arrive in Washington?
The Great Blue Heron is in Washington all year. It turns up on about 29% of checklists at its peak (early September) and on 16% in its quietest week (mid February).
When do Great Blue Herons leave Washington?
The Great Blue Heron does not leave Washington: it is reported all year, from 16% of checklists in mid February to 29% in early September.
When is the best time to see a Great Blue Heron in Washington?
The Great Blue Heron is reported most often in early September, on about 29% of Washington checklists.
Where in Washington are Great Blue Herons seen most often?
By county, Skagit County, Wahkiakum County, and Cowlitz County have the highest peak reporting rates for the Great Blue Heron (counties with at least 200 checklists).