WhenToBird

Purple Martin · Progne subis

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.

Purple Martins in Pennsylvania, species by species

SpeciesFirst arrivalsCommon byPeakMost gone byPeak %
Purple MartinApr 8-14Apr 15-21Jul 22-31Aug 15-216.4%
0%2%4%6%8%Purple MartinJanFebMarAprMayJunJulAugSepOctNovDec
  • Purple Martin
Share of complete checklists reporting each species, by week (4 per month). Gaps: fewer than 10 checklists that week.

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.

Where in Pennsylvania

Best counties for Purple Martin

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%

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 purple martins in Pennsylvania?
The Purple Martin is reported most often in late July, on about 6.4% of Pennsylvania checklists.