WhenToBird

Stelgidopteryx serripennis · Hirundinidae

When Do Northern Rough-winged Swallows Arrive in New Hampshire?

Adult Northern Rough-winged Swallow
Photo: Peter Chen 2.0, CC BY 4.0 via iNaturalist

Northern Rough-winged Swallows arrive in New Hampshire in the second week of April, peak in early May (4.8% of checklists), and most are gone by mid July.

When to look

First arrivalsApr 8-14the second week of April
Common byApr 8-14the second week of April
PeakMay 1-7early May
Most gone byJul 15-21mid July

Best: early May. First arrivals the second week of April; most are gone by mid July. Peak: on about 4.8% of New Hampshire checklists.

  1. Jannot usually seen
  2. Febnot usually seen
  3. Marrare
  4. Aprpeak season
  5. Maypeak season
  6. Juncommon
  7. Julcommon
  8. Auguncommon
  9. Sepnot usually seen
  10. Octnot usually seen
  11. Novnot usually seen
  12. Decnot usually seen

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

0%2%4%6%Jan 1-7: 0% of 8253 checklistsJan 8-14: 0% of 5998 checklistsJan 15-21: 0% of 5734 checklistsJan 22-31: 0% of 7776 checklistsFeb 1-7: 0% of 5253 checklistsFeb 8-14: 0% of 6802 checklistsFeb 15-21: 0% of 8852 checklistsFeb 22-28: 0% of 5792 checklistsMar 1-7: 0% of 6187 checklistsMar 8-14: 0% of 6977 checklistsMar 15-21: 0% of 7863 checklistsMar 22-31: 0% of 11746 checklistsApr 1-7: 0.6% of 9329 checklistsApr 8-14: 1.8% of 10499 checklistsApr 15-21: 3.2% of 10376 checklistsApr 22-30: 4.7% of 13086 checklistsMay 1-7: 5.3% of 13198 checklistsMay 8-14: 4.6% of 14980 checklistsMay 15-21: 4.2% of 12487 checklistsMay 22-31: 3.4% of 14294 checklistsJun 1-7: 3.2% of 8974 checklistsJun 8-14: 2.4% of 8395 checklistsJun 15-21: 2.4% of 7670 checklistsJun 22-30: 2.7% of 9188 checklistsJul 1-7: 2.4% of 7707 checklistsJul 8-14: 2.3% of 6554 checklistsJul 15-21: 1.6% of 6636 checklistsJul 22-31: 1.1% of 9599 checklistsAug 1-7: 0.6% of 6436 checklistsAug 8-14: 0.3% of 6477 checklistsAug 15-21: 0.2% of 6510 checklistsAug 22-31: 0.1% of 9762 checklistsSep 1-7: 0.1% of 6700 checklistsSep 8-14: 0.1% of 6012 checklistsSep 15-21: 0% of 6238 checklistsSep 22-30: 0.1% of 7619 checklistsOct 1-7: 0% of 6702 checklistsOct 8-14: 0% of 6863 checklistsOct 15-21: 0% of 6284 checklistsOct 22-31: 0% of 8287 checklistsNov 1-7: 0% of 7584 checklistsNov 8-14: 0% of 6056 checklistsNov 15-21: 0% of 5597 checklistsNov 22-30: 0% of 7140 checklistsDec 1-7: 0% of 4623 checklistsDec 8-14: 0% of 4920 checklistsDec 15-21: 0% of 6416 checklistsDec 22-31: 0% of 7659 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 New Hampshire 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 New Hampshire

Best counties

Share of checklists at the peak
  1. Cheshire CountyBest early May · 1289 checklists that week, 39,834 in all7.7%
  2. Strafford CountyBest early May · 1458 checklists that week, 41,888 in all7.5%
  3. Merrimack CountyBest late April · 1386 checklists that week, 36,980 in all6.7%
  4. Rockingham CountyBest early May · 2815 checklists that week, 84,864 in all5.3%
  5. Sullivan CountyBest the second week of May · 482 checklists that week, 13,105 in all4.3%
  6. Hillsborough CountyBest the second week of May · 2163 checklists that week, 50,125 in all4.0%

Best spots

Share of checklists at the peak
  1. Cocheco River ReservoirStrafford County, best mid June · 21 checklists that week, 2,281 in all47%
  2. Pine Road SiteRockingham County, best the second week of May · 142 checklists that week, 1,105 in all44%
  3. Manchester Cedar SwampHillsborough County, best the second week of May · 40 checklists that week, 496 in all41%
  4. Town of Exeter Sewerage Lagoons ReservoirRockingham County, best early June · 106 checklists that week, 2,293 in all40%
  5. Wilder Management AreaGrafton County, best the second week of May · 28 checklists that week, 543 in all38%

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

Best time of day

In New Hampshire, the Northern Rough-winged Swallow is most often listed on checklists started between 6 and 8 am (2.1% of those checklists).

0%1%2%3%12 am: too few checklists (219) to judge1 am: too few checklists (192) to judge2 am: too few checklists (176) to judge3 am: too few checklists (234) to judge4 am: too few checklists (1042) to judge5 am: too few checklists (6352) to judge6 am: 2.7% of 23140 checklists7 am: 1.8% of 43401 checklists8 am: 1.5% of 48039 checklists9 am: 1.3% of 43328 checklists10 am: 1.2% of 37073 checklists11 am: 1.0% of 32028 checklists12 pm: 1.0% of 27396 checklists1 pm: 0.9% of 25182 checklists2 pm: 0.9% of 24318 checklists3 pm: 1.0% of 21974 checklists4 pm: 1.2% of 17958 checklists5 pm: 1.4% of 14528 checklists6 pm: 1.3% of 9144 checklists7 pm: too few checklists (5341) to judge8 pm: too few checklists (1845) to judge9 pm: too few checklists (578) to judge10 pm: too few checklists (346) to judge11 pm: too few checklists (256) 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%
April0.6%1.8%3.2%4.7%
May5.3%4.6%4.2%3.4%
June3.2%2.4%2.4%2.7%
July2.4%2.3%1.6%1.1%
August0.6%0.3%0.2%0.1%
September0.1%0.1%0%0.1%
October0%0%0%0%
November0%0%0%0%
December0%0%0%0%

Neighboring states

  • Massachusetts: arrives early April, 1 week earlier than New Hampshire
  • Vermont: arrives the second week of April, in the same week than New Hampshire
  • Rhode Island: arrives early April, 1 week earlier than New Hampshire
  • Maine: arrives mid April, 1 week later than New Hampshire

Common questions

When do Northern Rough-winged Swallows arrive in New Hampshire?
Northern Rough-winged Swallows arrive in New Hampshire in the second week of April, peak in early May (4.8% of checklists), and most are gone by mid July.
When do Northern Rough-winged Swallows leave New Hampshire?
Most Northern Rough-winged Swallows have left New Hampshire by mid July, when reports fall below half their usual rate. Stragglers are still reported until late July.
When is the best time to see a Northern Rough-winged Swallow in New Hampshire?
The Northern Rough-winged Swallow is reported most often in early May, on about 4.8% of New Hampshire checklists.
Where in New Hampshire are Northern Rough-winged Swallows seen most often?
By county, Cheshire County, Strafford County, and Merrimack County have the highest peak reporting rates for the Northern Rough-winged Swallow (counties with at least 200 checklists).