WhenToBird

Hirundo rustica · Hirundinidae

When Do Barn Swallows Arrive in Maryland?

Adult Barn Swallow
Photo: Diego González Dopico, CC BY 4.0 via iNaturalist

Barn Swallows reach Maryland in early April, are common by mid April, peak in early August (31% of checklists), and most are gone by late August.

When to look

First arrivalsApr 1-7early April
Common byApr 15-21mid April
PeakAug 1-7early August
Most gone byAug 22-31late August

Best: early August. First arrivals early April; most are gone by late August. Peak: on about 31% of Maryland checklists.

  1. Jannot usually seen
  2. Febnot usually seen
  3. Marrare
  4. Aprcommon
  5. Maypeak season
  6. Junpeak season
  7. Julpeak season
  8. Augpeak season
  9. Sepuncommon
  10. Octnot usually seen
  11. Novnot usually seen
  12. Decnot usually seen

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

0%10%20%30%40%Jan 1-7: 0.1% of 28716 checklistsJan 8-14: 0.1% of 21449 checklistsJan 15-21: 0% of 21267 checklistsJan 22-31: 0% of 29144 checklistsFeb 1-7: 0% of 21347 checklistsFeb 8-14: 0% of 22166 checklistsFeb 15-21: 0% of 29986 checklistsFeb 22-28: 0% of 22427 checklistsMar 1-7: 0.1% of 21389 checklistsMar 8-14: 0.1% of 22192 checklistsMar 15-21: 0.2% of 22823 checklistsMar 22-31: 1.3% of 33720 checklistsApr 1-7: 4.6% of 25513 checklistsApr 8-14: 9.3% of 27718 checklistsApr 15-21: 15% of 29328 checklistsApr 22-30: 21% of 42595 checklistsMay 1-7: 26% of 38532 checklistsMay 8-14: 28% of 42722 checklistsMay 15-21: 29% of 31936 checklistsMay 22-31: 28% of 36903 checklistsJun 1-7: 26% of 23191 checklistsJun 8-14: 26% of 21853 checklistsJun 15-21: 27% of 21000 checklistsJun 22-30: 28% of 25133 checklistsJul 1-7: 28% of 18715 checklistsJul 8-14: 28% of 16376 checklistsJul 15-21: 29% of 15793 checklistsJul 22-31: 31% of 21969 checklistsAug 1-7: 32% of 16013 checklistsAug 8-14: 31% of 15249 checklistsAug 15-21: 26% of 15674 checklistsAug 22-31: 16% of 24925 checklistsSep 1-7: 8.0% of 19808 checklistsSep 8-14: 3.6% of 18513 checklistsSep 15-21: 1.6% of 21901 checklistsSep 22-30: 1.0% of 22901 checklistsOct 1-7: 0.6% of 19111 checklistsOct 8-14: 0.3% of 18482 checklistsOct 15-21: 0.2% of 17380 checklistsOct 22-31: 0.2% of 23992 checklistsNov 1-7: 0.1% of 17915 checklistsNov 8-14: 0.1% of 18905 checklistsNov 15-21: 0% of 16259 checklistsNov 22-30: 0.1% of 22852 checklistsDec 1-7: 0% of 16108 checklistsDec 8-14: 0.1% of 16512 checklistsDec 15-21: 0.1% of 18952 checklistsDec 22-31: 0% of 29728 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 Maryland 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 Maryland

Best counties

Share of checklists at the peak
  1. Queen Anne's CountyBest early August · 590 checklists that week, 26,875 in all57%
  2. Somerset CountyBest late July · 196 checklists that week, 9,451 in all52%
  3. Kent CountyBest the second week of August · 185 checklists that week, 13,396 in all51%
  4. Harford CountyBest early August · 447 checklists that week, 39,311 in all46%
  5. Talbot CountyBest late July · 630 checklists that week, 31,140 in all46%
  6. Dorchester CountyBest the second week of August · 247 checklists that week, 26,161 in all45%

Best spots

Share of checklists at the peak
  1. Gerber KnollHoward County, best early August · 20 checklists that week, 922 in all100%
  2. Schoolhouse PondPrince George's County, best early June · 31 checklists that week, 2,059 in all98%
  3. Lynwood T Kellam Memorial Recreational ParkCalvert County, best early July · 24 checklists that week, 375 in all98%
  4. JenkinsBaltimore County, best the second week of May · 25 checklists that week, 1,145 in all97%
  5. Whittier Lake Park (City of Frederick)Frederick County, best the second week of July · 23 checklists that week, 953 in all96%

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

Best time of day

In Maryland, the Barn Swallow is most often listed on checklists started between 6 and 8 am (16% of those checklists).

0%10%20%30%12 am: too few checklists (486) to judge1 am: too few checklists (451) to judge2 am: too few checklists (447) to judge3 am: too few checklists (766) to judge4 am: too few checklists (2076) to judge5 am: too few checklists (11098) to judge6 am: 22% of 56604 checklists7 am: 14% of 139255 checklists8 am: 11% of 148626 checklists9 am: 11% of 126820 checklists10 am: 10% of 106973 checklists11 am: 9.3% of 87483 checklists12 pm: 8.5% of 74808 checklists1 pm: 7.9% of 69428 checklists2 pm: 7.3% of 67800 checklists3 pm: 7.2% of 67688 checklists4 pm: 8.6% of 60927 checklists5 pm: 12% of 43876 checklists6 pm: 16% of 32930 checklists7 pm: too few checklists (19051) to judge8 pm: too few checklists (5708) to judge9 pm: too few checklists (1977) to judge10 pm: too few checklists (1170) to judge11 pm: too few checklists (635) 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
January0.1%0.1%0%0%
February0%0%0%0%
March0.1%0.1%0.2%1.3%
April4.6%9.3%15%21%
May26%28%29%28%
June26%26%27%28%
July28%28%29%31%
August32%31%26%16%
September8.0%3.6%1.6%1.0%
October0.6%0.3%0.2%0.2%
November0.1%0.1%0%0.1%
December0%0.1%0.1%0%

Neighboring states

  • District of Columbia: arrives late March, 1 week earlier than Maryland
  • Delaware: arrives the second week of April, 1 week later than Maryland
  • Virginia: arrives early April, in the same week than Maryland
  • Pennsylvania: arrives early April, in the same week than Maryland

Common questions

When do Barn Swallows arrive in Maryland?
Barn Swallows reach Maryland in early April, are common by mid April, peak in early August (31% of checklists), and most are gone by late August.
When do Barn Swallows leave Maryland?
Most Barn Swallows have left Maryland by late August, when reports fall below half their usual rate. Stragglers are still reported until the second week of September.
When is the best time to see a Barn Swallow in Maryland?
The Barn Swallow is reported most often in early August, on about 31% of Maryland checklists.
Where in Maryland are Barn Swallows seen most often?
By county, Queen Anne's County, Somerset County, and Kent County have the highest peak reporting rates for the Barn Swallow (counties with at least 200 checklists).