WhenToBird

Progne subis · Hirundinidae

When Do Purple Martins Arrive in Pennsylvania?

Adult female Purple Martin
Photo: Ron Bondy, CC BY-SA 4.0 via iNaturalist

Purple Martins reach Pennsylvania in the second week of April, are common by mid April, peak in late July (6.4% of checklists), and most are gone by mid August.

When to look

First arrivalsApr 8-14the second week of April
Common byApr 15-21mid April
PeakJul 22-31late July
Most gone byAug 15-21mid August

Best: late July. First arrivals the second week of April; most are gone by mid August. Peak: on about 6.4% of Pennsylvania checklists.

  1. Jannot usually seen
  2. Febnot usually seen
  3. Marrare
  4. Apruncommon
  5. Maycommon
  6. Juncommon
  7. Julpeak season
  8. Augpeak season
  9. Seprare
  10. Octnot usually seen
  11. Novnot usually seen
  12. Decnot usually seen

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

0%2%4%6%8%Jan 1-7: 0% of 47145 checklistsJan 8-14: 0% of 35840 checklistsJan 15-21: 0% of 35423 checklistsJan 22-31: 0% of 49126 checklistsFeb 1-7: 0% of 36366 checklistsFeb 8-14: 0% of 42248 checklistsFeb 15-21: 0% of 55888 checklistsFeb 22-28: 0% of 42050 checklistsMar 1-7: 0% of 42709 checklistsMar 8-14: 0% of 43985 checklistsMar 15-21: 0.1% of 44547 checklistsMar 22-31: 0.2% of 66940 checklistsApr 1-7: 0.8% of 51147 checklistsApr 8-14: 1.7% of 54868 checklistsApr 15-21: 2.2% of 57252 checklistsApr 22-30: 2.6% of 81727 checklistsMay 1-7: 2.6% of 76472 checklistsMay 8-14: 2.7% of 79341 checklistsMay 15-21: 3.5% of 61724 checklistsMay 22-31: 3.8% of 70722 checklistsJun 1-7: 3.9% of 45652 checklistsJun 8-14: 3.6% of 41810 checklistsJun 15-21: 3.6% of 38973 checklistsJun 22-30: 3.6% of 44255 checklistsJul 1-7: 3.9% of 34822 checklistsJul 8-14: 5.0% of 31104 checklistsJul 15-21: 6.5% of 29262 checklistsJul 22-31: 6.8% of 41436 checklistsAug 1-7: 5.7% of 29189 checklistsAug 8-14: 4.6% of 28840 checklistsAug 15-21: 3.1% of 29948 checklistsAug 22-31: 1.4% of 48235 checklistsSep 1-7: 0.6% of 37175 checklistsSep 8-14: 0.2% of 36527 checklistsSep 15-21: 0.1% of 37261 checklistsSep 22-30: 0.1% of 43583 checklistsOct 1-7: 0.1% of 35352 checklistsOct 8-14: 0% of 35560 checklistsOct 15-21: 0.1% of 33119 checklistsOct 22-31: 0% of 44654 checklistsNov 1-7: 0% of 32965 checklistsNov 8-14: 0% of 31305 checklistsNov 15-21: 0% of 29471 checklistsNov 22-30: 0% of 38642 checklistsDec 1-7: 0% of 28779 checklistsDec 8-14: 0% of 29486 checklistsDec 15-21: 0% of 37465 checklistsDec 22-31: 0% of 50651 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 Pennsylvania 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 Pennsylvania

Best counties

Share of checklists at the peak
  1. Erie CountyBest early August · 692 checklists that week, 49,012 in all29%
  2. Crawford CountyBest late July · 407 checklists that week, 23,552 in all27%
  3. Lancaster CountyBest mid July · 1464 checklists that week, 97,892 in all18%
  4. Chester CountyBest late July · 2547 checklists that week, 144,121 in all18%
  5. Mercer CountyBest late July · 354 checklists that week, 17,853 in all17%
  6. Mifflin CountyBest early July · 135 checklists that week, 6,998 in all16%

Best spots

Share of checklists at the peak
  1. Greencastle ReservoirFranklin County, best mid June · 33 checklists that week, 2,061 in all96%
  2. State Game Land 214Crawford County, best the second week of June · 58 checklists that week, 2,101 in all90%
  3. Beltzville State Park (Beltzville Lake)Carbon County, best late May · 22 checklists that week, 306 in all84%
  4. Coopers LakeButler County, best late May · 21 checklists that week, 1,149 in all83%

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

Best time of day

In Pennsylvania, the Purple Martin is most often listed on checklists started between 6 and 8 pm (2.7% of those checklists).

0%1%2%3%4%12 am: too few checklists (1558) to judge1 am: too few checklists (1136) to judge2 am: too few checklists (839) to judge3 am: too few checklists (842) to judge4 am: too few checklists (2550) to judge5 am: too few checklists (18294) to judge6 am: 2.4% of 92903 checklists7 am: 1.6% of 241233 checklists8 am: 1.5% of 271994 checklists9 am: 1.5% of 236842 checklists10 am: 1.3% of 199508 checklists11 am: 1.3% of 161893 checklists12 pm: 1.2% of 143945 checklists1 pm: 1.2% of 134352 checklists2 pm: 1.2% of 129692 checklists3 pm: 1.2% of 126132 checklists4 pm: 1.3% of 115055 checklists5 pm: 1.8% of 90719 checklists6 pm: 2.4% of 67534 checklists7 pm: 3.0% of 43004 checklists8 pm: too few checklists (13966) to judge9 pm: too few checklists (3913) to judge10 pm: too few checklists (1989) to judge11 pm: too few checklists (1146) 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%0%0.1%0.2%
April0.8%1.7%2.2%2.6%
May2.6%2.7%3.5%3.8%
June3.9%3.6%3.6%3.6%
July3.9%5.0%6.5%6.8%
August5.7%4.6%3.1%1.4%
September0.6%0.2%0.1%0.1%
October0.1%0%0.1%0%
November0%0%0%0%
December0%0%0%0%

Neighboring states

  • Maryland: arrives late March, 2 weeks earlier than Pennsylvania
  • District of Columbia: arrives late March, 2 weeks earlier than Pennsylvania
  • Delaware: arrives late March, 2 weeks earlier than Pennsylvania
  • New Jersey: arrives early April, 1 week earlier than Pennsylvania

Common questions

When do Purple Martins arrive in Pennsylvania?
Purple Martins reach Pennsylvania in the second week of April, are common by mid April, peak in late July (6.4% of checklists), and most are gone by mid August.
When do Purple Martins leave Pennsylvania?
Most Purple Martins have left Pennsylvania by mid August, when reports fall below half their usual rate. Stragglers are still reported until late August.
When is the best time to see a Purple Martin in Pennsylvania?
The Purple Martin is reported most often in late July, on about 6.4% of Pennsylvania checklists.
Where in Pennsylvania are Purple Martins seen most often?
By county, Erie County, Crawford County, and Lancaster County have the highest peak reporting rates for the Purple Martin (counties with at least 200 checklists).