WhenToBird

Dumetella carolinensis · Mimidae

When Do Gray Catbirds Arrive in Pennsylvania?

Adult Gray Catbird
Photo: Melanie Gaddy, CC0 1.0 via iNaturalist

Gray Catbirds reach Pennsylvania in mid April, are common by late April, peak in mid May (64% of checklists), and most are gone by early October.

When to look

First arrivalsApr 15-21mid April
Common byApr 22-30late April
PeakMay 15-21mid May
Most gone byOct 1-7early October

Best: mid May. First arrivals mid April; most are gone by early October. Peak: on about 64% of Pennsylvania checklists.

  1. Jannot usually seen
  2. Febnot usually seen
  3. Marnot usually seen
  4. Aprcommon
  5. Maypeak season
  6. Junpeak season
  7. Julpeak season
  8. Augpeak season
  9. Seppeak season
  10. Octcommon
  11. Novrare
  12. Decnot usually seen

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

0%20%40%60%80%Jan 1-7: 0.5% of 47145 checklistsJan 8-14: 0.4% of 35840 checklistsJan 15-21: 0.3% of 35423 checklistsJan 22-31: 0.4% of 49126 checklistsFeb 1-7: 0.3% of 36366 checklistsFeb 8-14: 0.2% of 42248 checklistsFeb 15-21: 0.2% of 55888 checklistsFeb 22-28: 0.2% of 42050 checklistsMar 1-7: 0.2% of 42709 checklistsMar 8-14: 0.2% of 43985 checklistsMar 15-21: 0.2% of 44547 checklistsMar 22-31: 0.2% of 66940 checklistsApr 1-7: 0.3% of 51147 checklistsApr 8-14: 0.4% of 54868 checklistsApr 15-21: 2.3% of 57252 checklistsApr 22-30: 25% of 81727 checklistsMay 1-7: 58% of 76472 checklistsMay 8-14: 64% of 79341 checklistsMay 15-21: 66% of 61724 checklistsMay 22-31: 61% of 70722 checklistsJun 1-7: 59% of 45652 checklistsJun 8-14: 57% of 41810 checklistsJun 15-21: 57% of 38973 checklistsJun 22-30: 58% of 44255 checklistsJul 1-7: 57% of 34822 checklistsJul 8-14: 57% of 31104 checklistsJul 15-21: 55% of 29262 checklistsJul 22-31: 55% of 41436 checklistsAug 1-7: 54% of 29189 checklistsAug 8-14: 53% of 28840 checklistsAug 15-21: 54% of 29948 checklistsAug 22-31: 55% of 48235 checklistsSep 1-7: 56% of 37175 checklistsSep 8-14: 57% of 36527 checklistsSep 15-21: 57% of 37261 checklistsSep 22-30: 52% of 43583 checklistsOct 1-7: 40% of 35352 checklistsOct 8-14: 24% of 35560 checklistsOct 15-21: 12% of 33119 checklistsOct 22-31: 5.4% of 44654 checklistsNov 1-7: 2.2% of 32965 checklistsNov 8-14: 1.6% of 31305 checklistsNov 15-21: 0.9% of 29471 checklistsNov 22-30: 0.8% of 38642 checklistsDec 1-7: 0.9% of 28779 checklistsDec 8-14: 0.8% of 29486 checklistsDec 15-21: 0.6% of 37465 checklistsDec 22-31: 0.5% 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.

Embed this map on your site

Where in Pennsylvania

Best counties

Share of checklists at the peak
  1. Chester CountyBest mid May · 3770 checklists that week, 144,121 in all83%
  2. Delaware CountyBest the second week of May · 2519 checklists that week, 76,406 in all82%
  3. Bucks CountyBest the second week of May · 3395 checklists that week, 95,030 in all81%
  4. Philadelphia CountyBest the second week of May · 4389 checklists that week, 96,503 in all80%
  5. Lehigh CountyBest early July · 662 checklists that week, 41,072 in all77%
  6. Montgomery CountyBest mid May · 5007 checklists that week, 184,237 in all77%

Best spots

Share of checklists at the peak
  1. State Game Land 145Lebanon County, best mid September · 23 checklists that week, 1,030 in all100%
  2. Houston PlaygroundPhiladelphia County, best early July · 22 checklists that week, 2,488 in all100%
  3. Ridley Creek State Park (Hunting Hill)Delaware County, best the second week of June · 25 checklists that week, 1,073 in all100%
  4. Penn State ArboretumCentre County, best late August · 37 checklists that week, 1,067 in all100%
  5. Riverfront Park 1Lycoming County, best late May · 36 checklists that week, 752 in all100%
  6. Hatfield Township Nature AreaMontgomery County, best mid May · 26 checklists that week, 242 in all100%

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

Best time of day

In Pennsylvania, the Gray Catbird is most often listed on checklists started between 6 and 8 am (40% of those checklists).

0%20%40%60%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: 51% of 92903 checklists7 am: 36% of 241233 checklists8 am: 31% of 271994 checklists9 am: 27% of 236842 checklists10 am: 23% of 199508 checklists11 am: 20% of 161893 checklists12 pm: 19% of 143945 checklists1 pm: 18% of 134352 checklists2 pm: 17% of 129692 checklists3 pm: 18% of 126132 checklists4 pm: 21% of 115055 checklists5 pm: 29% of 90719 checklists6 pm: 36% of 67534 checklists7 pm: 40% 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
January0.5%0.4%0.3%0.4%
February0.3%0.2%0.2%0.2%
March0.2%0.2%0.2%0.2%
April0.3%0.4%2.3%25%
May58%64%66%61%
June59%57%57%58%
July57%57%55%55%
August54%53%54%55%
September56%57%57%52%
October40%24%12%5.4%
November2.2%1.6%0.9%0.8%
December0.9%0.8%0.6%0.5%

Neighboring states

  • Maryland: arrives mid April, in the same week than Pennsylvania
  • District of Columbia: arrives mid April, in the same week than Pennsylvania
  • Delaware: arrives mid April, in the same week than Pennsylvania
  • New Jersey: arrives mid April, in the same week than Pennsylvania

Common questions

When do Gray Catbirds arrive in Pennsylvania?
Gray Catbirds reach Pennsylvania in mid April, are common by late April, peak in mid May (64% of checklists), and most are gone by early October.
When do Gray Catbirds leave Pennsylvania?
Most Gray Catbirds have left Pennsylvania by early October, when reports fall below half their usual rate. Stragglers are still reported until late October.
When is the best time to see a Gray Catbird in Pennsylvania?
The Gray Catbird is reported most often in mid May, on about 64% of Pennsylvania checklists.
Where in Pennsylvania are Gray Catbirds seen most often?
By county, Chester County, Delaware County, and Bucks County have the highest peak reporting rates for the Gray Catbird (counties with at least 200 checklists).