WhenToBird

Egretta thula · Ardeidae

When Do Snowy Egrets Arrive in Pennsylvania?

Adult Snowy Egret
Photo: Matt Muir, CC BY 4.0 via iNaturalist

Snowy Egrets mostly pass through Pennsylvania: they arrive in mid July, peak in the second week of August (1.0% of checklists), and most are gone by the second week of September.

When to look

First arrivalsJul 15-21mid July
Common byJul 15-21mid July
PeakAug 8-14the second week of August
Most gone bySep 8-14the second week of September

Best: the second week of August. First arrivals mid July; most are gone by the second week of September. Peak: on about 1.0% of Pennsylvania checklists.

  1. Jannot usually seen
  2. Febnot usually seen
  3. Marnot usually seen
  4. Aprrare
  5. Mayrare
  6. Junrare
  7. Julcommon
  8. Augpeak season
  9. Sepcommon
  10. Octrare
  11. Novnot usually seen
  12. Decnot usually seen

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

0%0.5%1%1.5%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% of 44547 checklistsMar 22-31: 0% of 66940 checklistsApr 1-7: 0% of 51147 checklistsApr 8-14: 0.1% of 54868 checklistsApr 15-21: 0.1% of 57252 checklistsApr 22-30: 0.1% of 81727 checklistsMay 1-7: 0.1% of 76472 checklistsMay 8-14: 0.1% of 79341 checklistsMay 15-21: 0.1% of 61724 checklistsMay 22-31: 0.1% of 70722 checklistsJun 1-7: 0.1% of 45652 checklistsJun 8-14: 0.1% of 41810 checklistsJun 15-21: 0.1% of 38973 checklistsJun 22-30: 0.1% of 44255 checklistsJul 1-7: 0% of 34822 checklistsJul 8-14: 0.1% of 31104 checklistsJul 15-21: 0.3% of 29262 checklistsJul 22-31: 0.7% of 41436 checklistsAug 1-7: 1.2% of 29189 checklistsAug 8-14: 1.0% of 28840 checklistsAug 15-21: 0.9% of 29948 checklistsAug 22-31: 0.6% of 48235 checklistsSep 1-7: 0.6% of 37175 checklistsSep 8-14: 0.4% of 36527 checklistsSep 15-21: 0.2% of 37261 checklistsSep 22-30: 0.2% of 43583 checklistsOct 1-7: 0.1% of 35352 checklistsOct 8-14: 0.1% of 35560 checklistsOct 15-21: 0.1% of 33119 checklistsOct 22-31: 0.1% 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. Philadelphia CountyBest the second week of August · 1241 checklists that week, 96,503 in all14%
  2. Dauphin CountyBest late July · 741 checklists that week, 35,877 in all6.4%
  3. Snyder CountyBest the second week of August · 53 checklists that week, 5,676 in all3.4%
  4. Northumberland CountyBest early August · 139 checklists that week, 9,183 in all2.6%
  5. Lancaster CountyBest mid August · 1431 checklists that week, 97,892 in all2.0%
  6. Montgomery CountyBest early August · 2639 checklists that week, 184,237 in all2.0%

Best spots

Share of checklists at the peak
  1. ReservoirChester County, best late July · 21 checklists that week, 137 in all63%
  2. John Heinz National Wildlife Refuge at TinicumPhiladelphia County, best the second week of August · 354 checklists that week, 18,127 in all45%
  3. Green Lane ReservoirMontgomery County, best early August · 146 checklists that week, 6,265 in all33%
  4. Wildwood ParkDauphin County, best late July · 145 checklists that week, 5,421 in all29%
  5. Shenango River Lake (Daley Run)Mercer County, best late August · 20 checklists that week, 220 in all29%

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

Best time of day

In Pennsylvania, the Snowy Egret is most often listed on checklists started between 5 and 7 pm (0.2% of those checklists).

0%0.5%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: 0.2% of 92903 checklists7 am: 0.1% of 241233 checklists8 am: 0.1% of 271994 checklists9 am: 0.1% of 236842 checklists10 am: 0.1% of 199508 checklists11 am: 0.1% of 161893 checklists12 pm: 0.1% of 143945 checklists1 pm: 0.1% of 134352 checklists2 pm: 0.1% of 129692 checklists3 pm: 0.1% of 126132 checklists4 pm: 0.1% of 115055 checklists5 pm: 0.2% of 90719 checklists6 pm: 0.2% of 67534 checklists7 pm: 0.1% 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%0%
April0%0.1%0.1%0.1%
May0.1%0.1%0.1%0.1%
June0.1%0.1%0.1%0.1%
July0%0.1%0.3%0.7%
August1.2%1.0%0.9%0.6%
September0.6%0.4%0.2%0.2%
October0.1%0.1%0.1%0.1%
November0%0%0%0%
December0%0%0%0%

Neighboring states

  • Maryland: arrives early April, 14 weeks earlier than Pennsylvania
  • Delaware: arrives late March, 15 weeks earlier than Pennsylvania
  • New Jersey: arrives late March, 15 weeks earlier than Pennsylvania
  • New York: arrives the second week of April, 13 weeks earlier than Pennsylvania

Common questions

When do Snowy Egrets arrive in Pennsylvania?
Snowy Egrets mostly pass through Pennsylvania: they arrive in mid July, peak in the second week of August (1.0% of checklists), and most are gone by the second week of September.
When do Snowy Egrets leave Pennsylvania?
Most Snowy Egrets have left Pennsylvania by the second week of September, when reports fall below half their usual rate.
When is the best time to see a Snowy Egret in Pennsylvania?
The Snowy Egret is reported most often in the second week of August, on about 1.0% of Pennsylvania checklists.
Where in Pennsylvania are Snowy Egrets seen most often?
By county, Philadelphia County, Dauphin County, and Snyder County have the highest peak reporting rates for the Snowy Egret (counties with at least 200 checklists).