WhenToBird

Larus heermanni · Laridae

When Do Heermann's Gulls Arrive in Oregon?

Adult Heermann's Gull
Photo: Ken Clark, CC BY 4.0 via iNaturalist

Heermann's Gulls arrive in Oregon in early July, peak in late July (1.8% of checklists), and most are gone by early November.

When to look

First arrivalsJul 1-7early July
Common byJul 1-7early July
PeakJul 22-31late July
Most gone byNov 1-7early November

Best: late July. First arrivals early July; most are gone by early November. Peak: on about 1.8% of Oregon checklists.

  1. Jannot usually seen
  2. Febnot usually seen
  3. Marnot usually seen
  4. Aprnot usually seen
  5. Maynot usually seen
  6. Jununcommon
  7. Julpeak season
  8. Augpeak season
  9. Seppeak season
  10. Octpeak season
  11. Novcommon
  12. Decrare

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

0%1%2%3%Jan 1-7: 0.1% of 34973 checklistsJan 8-14: 0% of 26807 checklistsJan 15-21: 0% of 26567 checklistsJan 22-31: 0% of 36019 checklistsFeb 1-7: 0% of 24020 checklistsFeb 8-14: 0.1% of 25765 checklistsFeb 15-21: 0% of 31019 checklistsFeb 22-28: 0% of 24582 checklistsMar 1-7: 0% of 24834 checklistsMar 8-14: 0% of 24642 checklistsMar 15-21: 0% of 27420 checklistsMar 22-31: 0% of 39913 checklistsApr 1-7: 0% of 28817 checklistsApr 8-14: 0.1% of 31221 checklistsApr 15-21: 0.1% of 34402 checklistsApr 22-30: 0.1% of 47144 checklistsMay 1-7: 0.1% of 37716 checklistsMay 8-14: 0.1% of 39651 checklistsMay 15-21: 0.1% of 37496 checklistsMay 22-31: 0.1% of 56967 checklistsJun 1-7: 0.1% of 35893 checklistsJun 8-14: 0.2% of 31880 checklistsJun 15-21: 0.2% of 30942 checklistsJun 22-30: 0.4% of 38478 checklistsJul 1-7: 1.1% of 27409 checklistsJul 8-14: 1.3% of 25161 checklistsJul 15-21: 1.7% of 25473 checklistsJul 22-31: 1.9% of 33920 checklistsAug 1-7: 1.7% of 24310 checklistsAug 8-14: 1.6% of 23675 checklistsAug 15-21: 1.7% of 23623 checklistsAug 22-31: 1.6% of 33762 checklistsSep 1-7: 1.2% of 25120 checklistsSep 8-14: 2.1% of 24458 checklistsSep 15-21: 1.6% of 25528 checklistsSep 22-30: 1.7% of 31631 checklistsOct 1-7: 1.4% of 25498 checklistsOct 8-14: 1.8% of 25161 checklistsOct 15-21: 1.4% of 23701 checklistsOct 22-31: 1.4% of 30996 checklistsNov 1-7: 1.2% of 21089 checklistsNov 8-14: 0.6% of 21880 checklistsNov 15-21: 0.3% of 21501 checklistsNov 22-30: 0.2% of 28930 checklistsDec 1-7: 0.1% of 19807 checklistsDec 8-14: 0.1% of 21022 checklistsDec 15-21: 0.1% of 24817 checklistsDec 22-31: 0.1% of 37592 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 Oregon 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 Oregon

Best counties

Share of checklists at the peak
  1. Clatsop CountyBest mid September · 995 checklists that week, 44,300 in all17%
  2. Lincoln CountyBest mid October · 1040 checklists that week, 66,994 in all11%
  3. Tillamook CountyBest mid September · 880 checklists that week, 45,809 in all10%
  4. Curry CountyBest the second week of July · 283 checklists that week, 12,513 in all9.4%
  5. Coos CountyBest late July · 610 checklists that week, 24,368 in all6.1%
  6. Douglas CountyBest early September · 346 checklists that week, 17,976 in all2.4%

Best spots

Share of checklists at the peak
  1. Hammond Boat BasinClatsop County, best mid September · 31 checklists that week, 507 in all86%
  2. Fort Stevens State Park (Social Security Beach)Clatsop County, best early September · 21 checklists that week, 367 in all84%
  3. D River State Recreation SiteLincoln County, best the second week of October · 24 checklists that week, 602 in all67%
  4. Hidden LakeTillamook County, best the second week of July · 27 checklists that week, 1,722 in all64%
  5. Seltzer ParkClatsop County, best late August · 92 checklists that week, 2,444 in all63%
  6. Siuslaw RiverLane County, best mid July · 27 checklists that week, 1,183 in all53%

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

Best time of day

In Oregon, the Heermann's Gull is most often listed on checklists started between 10 am and 12 pm (0.6% of those checklists).

0%0.5%1%12 am: too few checklists (1505) to judge1 am: too few checklists (675) to judge2 am: too few checklists (626) to judge3 am: too few checklists (1641) to judge4 am: too few checklists (3696) to judge5 am: too few checklists (14524) to judge6 am: 0.4% of 50677 checklists7 am: 0.5% of 125347 checklists8 am: 0.6% of 163668 checklists9 am: 0.5% of 160351 checklists10 am: 0.6% of 148940 checklists11 am: 0.6% of 124743 checklists12 pm: 0.6% of 112537 checklists1 pm: 0.6% of 98999 checklists2 pm: 0.6% of 94690 checklists3 pm: 0.5% of 87923 checklists4 pm: 0.5% of 75235 checklists5 pm: 0.5% of 54504 checklists6 pm: 0.5% of 40469 checklists7 pm: 0.3% of 33675 checklists8 pm: too few checklists (18715) to judge9 pm: too few checklists (5839) to judge10 pm: too few checklists (2704) to judge11 pm: too few checklists (1549) 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
January0.1%0%0%0%
February0%0.1%0%0%
March0%0%0%0%
April0%0.1%0.1%0.1%
May0.1%0.1%0.1%0.1%
June0.1%0.2%0.2%0.4%
July1.1%1.3%1.7%1.9%
August1.7%1.6%1.7%1.6%
September1.2%2.1%1.6%1.7%
October1.4%1.8%1.4%1.4%
November1.2%0.6%0.3%0.2%
December0.1%0.1%0.1%0.1%

Neighboring states

  • Washington: arrives early July, in the same week than Oregon
  • California: arrives late May, 5 weeks earlier than Oregon

Common questions

When do Heermann's Gulls arrive in Oregon?
Heermann's Gulls arrive in Oregon in early July, peak in late July (1.8% of checklists), and most are gone by early November.
When do Heermann's Gulls leave Oregon?
Most Heermann's Gulls have left Oregon by early November, when reports fall below half their usual rate.
When is the best time to see a Heermann's Gull in Oregon?
The Heermann's Gull is reported most often in late July, on about 1.8% of Oregon checklists.
Where in Oregon are Heermann's Gulls seen most often?
By county, Clatsop County, Lincoln County, and Tillamook County have the highest peak reporting rates for the Heermann's Gull (counties with at least 200 checklists).