WhenToBird

Falco columbarius · Falconidae

When Do Merlins Arrive in Washington?

Adult female Merlin
Photo: Cricket Raspet, CC BY 4.0 via iNaturalist

Merlins arrive in Washington in mid July, peak in late September (2.9% of checklists), and most are gone by late April.

When to look

First arrivalsJul 15-21mid July
Common byJul 15-21mid July
PeakSep 22-30late September
Most gone byApr 22-30late April

Best: late September. First arrivals mid July; most are gone by late April. Peak: on about 2.9% of Washington checklists.

  1. Jancommon
  2. Febcommon
  3. Maruncommon
  4. Aprcommon
  5. Mayuncommon
  6. Jununcommon
  7. Julcommon
  8. Augcommon
  9. Seppeak season
  10. Octpeak season
  11. Novpeak season
  12. Deccommon

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

0%1%2%3%4%Jan 1-7: 1.8% of 41928 checklistsJan 8-14: 1.7% of 31152 checklistsJan 15-21: 1.8% of 31753 checklistsJan 22-31: 1.8% of 42530 checklistsFeb 1-7: 1.4% of 29739 checklistsFeb 8-14: 1.3% of 32746 checklistsFeb 15-21: 1.3% of 40328 checklistsFeb 22-28: 1.1% of 28432 checklistsMar 1-7: 1.1% of 30758 checklistsMar 8-14: 1.1% of 29368 checklistsMar 15-21: 1.1% of 32580 checklistsMar 22-31: 1.2% of 45614 checklistsApr 1-7: 1.0% of 33997 checklistsApr 8-14: 1.3% of 34729 checklistsApr 15-21: 1.2% of 38474 checklistsApr 22-30: 1.2% of 52185 checklistsMay 1-7: 0.8% of 44236 checklistsMay 8-14: 0.5% of 48708 checklistsMay 15-21: 0.4% of 41742 checklistsMay 22-31: 0.3% of 57082 checklistsJun 1-7: 0.3% of 39193 checklistsJun 8-14: 0.3% of 36042 checklistsJun 15-21: 0.4% of 34003 checklistsJun 22-30: 0.5% of 39711 checklistsJul 1-7: 0.6% of 31949 checklistsJul 8-14: 0.7% of 29086 checklistsJul 15-21: 0.8% of 28045 checklistsJul 22-31: 1.3% of 38275 checklistsAug 1-7: 1.8% of 28846 checklistsAug 8-14: 1.6% of 28036 checklistsAug 15-21: 1.6% of 27614 checklistsAug 22-31: 1.8% of 40356 checklistsSep 1-7: 2.2% of 31214 checklistsSep 8-14: 2.8% of 27795 checklistsSep 15-21: 2.9% of 29677 checklistsSep 22-30: 3.1% of 35241 checklistsOct 1-7: 2.9% of 28605 checklistsOct 8-14: 2.8% of 28655 checklistsOct 15-21: 2.7% of 24643 checklistsOct 22-31: 2.6% of 34874 checklistsNov 1-7: 2.3% of 25658 checklistsNov 8-14: 2.2% of 25700 checklistsNov 15-21: 2.1% of 24331 checklistsNov 22-30: 1.9% of 32784 checklistsDec 1-7: 1.9% of 24099 checklistsDec 8-14: 2.0% of 23339 checklistsDec 15-21: 1.8% of 27666 checklistsDec 22-31: 1.9% 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. Ferry CountyBest the second week of September · 87 checklists that week, 5,106 in all8.7%
  2. Adams CountyBest early January · 11 checklists that week, 4,574 in all6.8%
  3. Skagit CountyBest late September · 1513 checklists that week, 78,154 in all6.1%
  4. Okanogan CountyBest mid September · 443 checklists that week, 23,048 in all5.6%
  5. Pacific CountyBest early November · 324 checklists that week, 19,516 in all5.6%
  6. Chelan CountyBest late September · 1038 checklists that week, 45,099 in all5.0%

Best spots

Share of checklists at the peak
  1. Railroad Bridge ParkClallam County, best late November · 33 checklists that week, 1,941 in all38%
  2. Saltese Flats Wetland Area (west)Spokane County, best the second week of August · 28 checklists that week, 1,083 in all33%
  3. Lake Roosevelt National Recreation AreaFerry County, best late August · 25 checklists that week, 307 in all33%
  4. BriarcrestKing County, best late March · 209 checklists that week, 285 in all29%
  5. Thomas LakeSnohomish County, best late August · 23 checklists that week, 683 in all28%

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

Best time of day

In Washington, the Merlin is most often listed on checklists started between 7 and 9 am (2.0% of those checklists).

0%1%2%3%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: 2.0% of 56744 checklists7 am: 2.0% of 133294 checklists8 am: 2.0% of 184196 checklists9 am: 1.6% of 186303 checklists10 am: 1.3% of 177063 checklists11 am: 1.2% of 154936 checklists12 pm: 1.1% of 138061 checklists1 pm: 1.3% of 127449 checklists2 pm: 1.4% of 121511 checklists3 pm: 1.3% of 107793 checklists4 pm: 1.1% of 82862 checklists5 pm: 1.2% of 57183 checklists6 pm: 1.0% 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
January1.8%1.7%1.8%1.8%
February1.4%1.3%1.3%1.1%
March1.1%1.1%1.1%1.2%
April1.0%1.3%1.2%1.2%
May0.8%0.5%0.4%0.3%
June0.3%0.3%0.4%0.5%
July0.6%0.7%0.8%1.3%
August1.8%1.6%1.6%1.8%
September2.2%2.8%2.9%3.1%
October2.9%2.8%2.7%2.6%
November2.3%2.2%2.1%1.9%
December1.9%2.0%1.8%1.9%

Neighboring states

  • Oregon: arrives mid September, 8 weeks later than Washington
  • Idaho: arrives the second week of September, 7 weeks later than Washington
  • Montana: arrives mid August, 4 weeks later than Washington
  • Nevada: arrives late September, 9 weeks later than Washington

Common questions

When do Merlins arrive in Washington?
Merlins arrive in Washington in mid July, peak in late September (2.9% of checklists), and most are gone by late April.
When do Merlins leave Washington?
Most Merlins have left Washington by late April, when reports fall below half their usual rate.
When is the best time to see a Merlin in Washington?
The Merlin is reported most often in late September, on about 2.9% of Washington checklists.
Where in Washington are Merlins seen most often?
By county, Ferry County, Adams County, and Skagit County have the highest peak reporting rates for the Merlin (counties with at least 200 checklists).