WhenToBird

Petrochelidon pyrrhonota · Hirundinidae

When Do Cliff Swallows Arrive in Oklahoma?

Adult Cliff Swallow
Photo: Dean Hester, CC BY 4.0 via iNaturalist

Cliff Swallows reach Oklahoma in late March, are common by the second week of April, peak in mid May (17% of checklists), and most are gone by early August.

When to look

First arrivalsMar 22-31late March
Common byApr 8-14the second week of April
PeakMay 15-21mid May
Most gone byAug 1-7early August

Best: mid May. First arrivals late March; most are gone by early August. Peak: on about 17% of Oklahoma checklists.

  1. Jannot usually seen
  2. Febnot usually seen
  3. Maruncommon
  4. Aprpeak season
  5. Maypeak season
  6. Junpeak season
  7. Julpeak season
  8. Augcommon
  9. Seprare
  10. Octnot usually seen
  11. Novnot usually seen
  12. Decnot usually seen

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

0%5%10%15%20%Jan 1-7: 0% of 6087 checklistsJan 8-14: 0% of 4350 checklistsJan 15-21: 0% of 4381 checklistsJan 22-31: 0% of 6165 checklistsFeb 1-7: 0% of 4259 checklistsFeb 8-14: 0% of 4589 checklistsFeb 15-21: 0% of 7001 checklistsFeb 22-28: 0% of 4482 checklistsMar 1-7: 0.1% of 4724 checklistsMar 8-14: 0.2% of 4571 checklistsMar 15-21: 0.8% of 4393 checklistsMar 22-31: 2.5% of 7544 checklistsApr 1-7: 5.1% of 5967 checklistsApr 8-14: 7.7% of 6543 checklistsApr 15-21: 12% of 7366 checklistsApr 22-30: 14% of 10618 checklistsMay 1-7: 16% of 8835 checklistsMay 8-14: 17% of 8247 checklistsMay 15-21: 17% of 6081 checklistsMay 22-31: 18% of 7283 checklistsJun 1-7: 16% of 4256 checklistsJun 8-14: 16% of 3774 checklistsJun 15-21: 17% of 3541 checklistsJun 22-30: 16% of 4159 checklistsJul 1-7: 13% of 3209 checklistsJul 8-14: 9.3% of 2916 checklistsJul 15-21: 8.6% of 2861 checklistsJul 22-31: 8.2% of 4146 checklistsAug 1-7: 7.3% of 3043 checklistsAug 8-14: 6.4% of 2839 checklistsAug 15-21: 4.0% of 3014 checklistsAug 22-31: 2.4% of 4759 checklistsSep 1-7: 1.1% of 3861 checklistsSep 8-14: 1.1% of 3748 checklistsSep 15-21: 0.8% of 3569 checklistsSep 22-30: 0.3% of 4830 checklistsOct 1-7: 0.1% of 3809 checklistsOct 8-14: 0.1% of 4142 checklistsOct 15-21: 0.1% of 3705 checklistsOct 22-31: 0.1% of 4738 checklistsNov 1-7: 0% of 3823 checklistsNov 8-14: 0% of 3849 checklistsNov 15-21: 0% of 3722 checklistsNov 22-30: 0% of 4795 checklistsDec 1-7: 0% of 3324 checklistsDec 8-14: 0% of 3574 checklistsDec 15-21: 0% of 3884 checklistsDec 22-31: 0% of 5774 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 Oklahoma 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 Oklahoma

Best counties

Share of checklists at the peak
  1. Tillman CountyBest mid July · 18 checklists that week, 1,199 in all61%
  2. Washita CountyBest early May · 18 checklists that week, 404 in all55%
  3. Greer CountyBest the second week of June · 18 checklists that week, 390 in all53%
  4. Alfalfa CountyBest early June · 44 checklists that week, 3,843 in all47%
  5. Grant CountyBest late May · 15 checklists that week, 307 in all42%
  6. Cotton CountyBest late June · 11 checklists that week, 765 in all38%

Best spots

Share of checklists at the peak
  1. Lake Thunderbird State ParkCleveland County, best the second week of May · 21 checklists that week, 824 in all87%
  2. Boomer Lake Park (Hazen Lake)Payne County, best early June · 22 checklists that week, 597 in all87%
  3. Lake Thunderbird State Park (Dave Blue Creek)Cleveland County, best mid May · 20 checklists that week, 373 in all82%
  4. Boomer Lake ParkPayne County, best late May · 106 checklists that week, 3,723 in all81%
  5. Salt Plains National Wildlife RefugeAlfalfa County, best late May · 24 checklists that week, 407 in all70%

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

Best time of day

In Oklahoma, the Cliff Swallow is most often listed on checklists started between 6 and 8 am (8.7% of those checklists).

0%5%10%15%12 am: too few checklists (91) to judge1 am: too few checklists (65) to judge2 am: too few checklists (73) to judge3 am: too few checklists (73) to judge4 am: too few checklists (100) to judge5 am: too few checklists (647) to judge6 am: 12% of 8353 checklists7 am: 7.5% of 24509 checklists8 am: 5.7% of 27848 checklists9 am: 5.5% of 25316 checklists10 am: 5.2% of 21161 checklists11 am: 4.7% of 18730 checklists12 pm: 5.0% of 16097 checklists1 pm: 4.8% of 14028 checklists2 pm: 4.9% of 13599 checklists3 pm: 4.0% of 14228 checklists4 pm: 4.1% of 14597 checklists5 pm: 5.0% of 12125 checklists6 pm: 6.4% of 9337 checklists7 pm: 8.4% of 6944 checklists8 pm: too few checklists (2403) to judge9 pm: too few checklists (459) to judge10 pm: too few checklists (226) to judge11 pm: too few checklists (141) 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%0%0%0%
February0%0%0%0%
March0.1%0.2%0.8%2.5%
April5.1%7.7%12%14%
May16%17%17%18%
June16%16%17%16%
July13%9.3%8.6%8.2%
August7.3%6.4%4.0%2.4%
September1.1%1.1%0.8%0.3%
October0.1%0.1%0.1%0.1%
November0%0%0%0%
December0%0%0%0%

Neighboring states

  • Kansas: arrives the second week of April, 2 weeks later than Oklahoma
  • Arkansas: arrives late March, in the same week than Oklahoma
  • Missouri: arrives early April, 1 week later than Oklahoma
  • Nebraska: arrives mid April, 3 weeks later than Oklahoma

Common questions

When do Cliff Swallows arrive in Oklahoma?
Cliff Swallows reach Oklahoma in late March, are common by the second week of April, peak in mid May (17% of checklists), and most are gone by early August.
When do Cliff Swallows leave Oklahoma?
Most Cliff Swallows have left Oklahoma by early August, when reports fall below half their usual rate. Stragglers are still reported until early September.
When is the best time to see a Cliff Swallow in Oklahoma?
The Cliff Swallow is reported most often in mid May, on about 17% of Oklahoma checklists.
Where in Oklahoma are Cliff Swallows seen most often?
By county, Tillman County, Washita County, and Greer County have the highest peak reporting rates for the Cliff Swallow (counties with at least 200 checklists).