WhenToBird

Quiscalus quiscula · Icteridae

When Do Common Grackles Arrive in Pennsylvania?

Adult Common Grackle
Photo: Derek Spencer, CC BY 4.0 via iNaturalist

Common Grackles reach Pennsylvania in early February, are common by late February, peak in late May (39% of checklists), and most are gone by the second week of August.

When to look

First arrivalsFeb 1-7early February
Common byFeb 22-28late February
PeakMay 22-31late May
Most gone byAug 8-14the second week of August

Best: late May. First arrivals early February; most are gone by the second week of August. Peak: on about 39% of Pennsylvania checklists.

  1. Janrare
  2. Febuncommon
  3. Marcommon
  4. Aprpeak season
  5. Maypeak season
  6. Junpeak season
  7. Julpeak season
  8. Augcommon
  9. Sepuncommon
  10. Octuncommon
  11. Novuncommon
  12. Decrare

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

0%10%20%30%40%Jan 1-7: 1.5% of 47145 checklistsJan 8-14: 1.5% of 35840 checklistsJan 15-21: 1.8% of 35423 checklistsJan 22-31: 2.0% of 49126 checklistsFeb 1-7: 2.3% of 36366 checklistsFeb 8-14: 4.6% of 42248 checklistsFeb 15-21: 8.2% of 55888 checklistsFeb 22-28: 16% of 42050 checklistsMar 1-7: 23% of 42709 checklistsMar 8-14: 27% of 43985 checklistsMar 15-21: 28% of 44547 checklistsMar 22-31: 29% of 66940 checklistsApr 1-7: 29% of 51147 checklistsApr 8-14: 30% of 54868 checklistsApr 15-21: 32% of 57252 checklistsApr 22-30: 34% of 81727 checklistsMay 1-7: 37% of 76472 checklistsMay 8-14: 38% of 79341 checklistsMay 15-21: 39% of 61724 checklistsMay 22-31: 39% of 70722 checklistsJun 1-7: 38% of 45652 checklistsJun 8-14: 37% of 41810 checklistsJun 15-21: 36% of 38973 checklistsJun 22-30: 34% of 44255 checklistsJul 1-7: 31% of 34822 checklistsJul 8-14: 28% of 31104 checklistsJul 15-21: 25% of 29262 checklistsJul 22-31: 22% of 41436 checklistsAug 1-7: 19% of 29189 checklistsAug 8-14: 17% of 28840 checklistsAug 15-21: 14% of 29948 checklistsAug 22-31: 13% of 48235 checklistsSep 1-7: 9.8% of 37175 checklistsSep 8-14: 7.5% of 36527 checklistsSep 15-21: 6.3% of 37261 checklistsSep 22-30: 5.6% of 43583 checklistsOct 1-7: 6.5% of 35352 checklistsOct 8-14: 7.2% of 35560 checklistsOct 15-21: 8.1% of 33119 checklistsOct 22-31: 8.2% of 44654 checklistsNov 1-7: 8.3% of 32965 checklistsNov 8-14: 6.7% of 31305 checklistsNov 15-21: 4.2% of 29471 checklistsNov 22-30: 2.7% of 38642 checklistsDec 1-7: 2.0% of 28779 checklistsDec 8-14: 1.7% of 29486 checklistsDec 15-21: 2.0% of 37465 checklistsDec 22-31: 1.5% 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. Montour CountyBest the second week of May · 276 checklists that week, 6,082 in all68%
  2. Juniata CountyBest mid June · 141 checklists that week, 9,807 in all60%
  3. Mifflin CountyBest early April · 142 checklists that week, 6,998 in all59%
  4. Lehigh CountyBest early June · 762 checklists that week, 41,072 in all59%
  5. Lycoming CountyBest the second week of May · 1102 checklists that week, 29,685 in all57%
  6. Snyder CountyBest late May · 290 checklists that week, 5,676 in all56%

Best spots

Share of checklists at the peak
  1. The Willows ParkDelaware County, best late April · 26 checklists that week, 549 in all98%
  2. The GutLycoming County, best late June · 52 checklists that week, 2,014 in all98%
  3. F. M. Kirby ParkLuzerne County, best the second week of May · 23 checklists that week, 254 in all96%

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

Best time of day

In Pennsylvania, the Common Grackle is most often listed on checklists started between 6 and 8 am (28% of those checklists).

0%10%20%30%40%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: 34% of 92903 checklists7 am: 26% of 241233 checklists8 am: 22% of 271994 checklists9 am: 19% of 236842 checklists10 am: 17% of 199508 checklists11 am: 15% of 161893 checklists12 pm: 14% of 143945 checklists1 pm: 14% of 134352 checklists2 pm: 14% of 129692 checklists3 pm: 15% of 126132 checklists4 pm: 17% of 115055 checklists5 pm: 23% of 90719 checklists6 pm: 25% of 67534 checklists7 pm: 24% 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
January1.5%1.5%1.8%2.0%
February2.3%4.6%8.2%16%
March23%27%28%29%
April29%30%32%34%
May37%38%39%39%
June38%37%36%34%
July31%28%25%22%
August19%17%14%13%
September9.8%7.5%6.3%5.6%
October6.5%7.2%8.1%8.2%
November8.3%6.7%4.2%2.7%
December2.0%1.7%2.0%1.5%

Neighboring states

  • Maryland: arrives early March, 4 weeks later than Pennsylvania
  • District of Columbia: arrives the second week of January, 3 weeks earlier than Pennsylvania
  • Delaware: arrives mid March, 6 weeks later than Pennsylvania
  • New Jersey: arrives early March, 4 weeks later than Pennsylvania

Common questions

When do Common Grackles arrive in Pennsylvania?
Common Grackles reach Pennsylvania in early February, are common by late February, peak in late May (39% of checklists), and most are gone by the second week of August.
When do Common Grackles leave Pennsylvania?
Most Common Grackles have left Pennsylvania by the second week of August, when reports fall below half their usual rate. Stragglers are still reported until mid November.
When is the best time to see a Common Grackle in Pennsylvania?
The Common Grackle is reported most often in late May, on about 39% of Pennsylvania checklists.
Where in Pennsylvania are Common Grackles seen most often?
By county, Montour County, Juniata County, and Mifflin County have the highest peak reporting rates for the Common Grackle (counties with at least 200 checklists).