WhenToBird

Falco peregrinus · Falconidae

When Do Peregrine Falcons Arrive in Maine?

Adult Peregrine Falcon
Photo: Andrea Poggi, CC BY 4.0 via iNaturalist

Peregrine Falcons arrive in Maine in early August, peak in late September (3.6% of checklists), and most are gone by late October.

When to look

First arrivalsAug 1-7early August
Common byAug 1-7early August
PeakSep 22-30late September
Most gone byOct 22-31late October

Best: late September. First arrivals early August; most are gone by late October. Peak: on about 3.6% of Maine checklists.

  1. Januncommon
  2. Febuncommon
  3. Maruncommon
  4. Apruncommon
  5. Mayuncommon
  6. Jununcommon
  7. Juluncommon
  8. Augcommon
  9. Seppeak season
  10. Octpeak season
  11. Novuncommon
  12. Decuncommon

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

0%2%4%6%Jan 1-7: 0.7% of 15499 checklistsJan 8-14: 0.9% of 11141 checklistsJan 15-21: 0.9% of 10729 checklistsJan 22-31: 0.7% of 15084 checklistsFeb 1-7: 0.9% of 9403 checklistsFeb 8-14: 0.6% of 11268 checklistsFeb 15-21: 0.6% of 14061 checklistsFeb 22-28: 0.7% of 9977 checklistsMar 1-7: 0.6% of 9649 checklistsMar 8-14: 0.5% of 11781 checklistsMar 15-21: 0.6% of 11613 checklistsMar 22-31: 0.5% of 17798 checklistsApr 1-7: 0.6% of 14638 checklistsApr 8-14: 0.7% of 16511 checklistsApr 15-21: 0.5% of 17164 checklistsApr 22-30: 0.6% of 22602 checklistsMay 1-7: 0.6% of 22556 checklistsMay 8-14: 0.5% of 27842 checklistsMay 15-21: 0.7% of 27748 checklistsMay 22-31: 0.7% of 38715 checklistsJun 1-7: 0.7% of 26916 checklistsJun 8-14: 0.6% of 23737 checklistsJun 15-21: 0.5% of 22733 checklistsJun 22-30: 0.5% of 28248 checklistsJul 1-7: 0.6% of 20290 checklistsJul 8-14: 0.6% of 18534 checklistsJul 15-21: 0.6% of 17319 checklistsJul 22-31: 0.9% of 22815 checklistsAug 1-7: 1.3% of 15004 checklistsAug 8-14: 1.6% of 14603 checklistsAug 15-21: 2.0% of 14972 checklistsAug 22-31: 2.0% of 19813 checklistsSep 1-7: 2.1% of 14567 checklistsSep 8-14: 2.2% of 14520 checklistsSep 15-21: 3.0% of 14339 checklistsSep 22-30: 4.5% of 16879 checklistsOct 1-7: 3.0% of 12959 checklistsOct 8-14: 2.0% of 13168 checklistsOct 15-21: 1.5% of 11184 checklistsOct 22-31: 1.0% of 13717 checklistsNov 1-7: 0.7% of 9823 checklistsNov 8-14: 0.7% of 9007 checklistsNov 15-21: 0.8% of 8528 checklistsNov 22-30: 0.8% of 10228 checklistsDec 1-7: 0.9% of 7505 checklistsDec 8-14: 0.7% of 7982 checklistsDec 15-21: 0.7% of 10455 checklistsDec 22-31: 0.7% of 14285 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 Maine 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 Maine

Best counties

Share of checklists at the peak
  1. Lincoln CountyBest late September · 2193 checklists that week, 59,429 in all13%
  2. York CountyBest late September · 2330 checklists that week, 101,844 in all5.6%
  3. Knox CountyBest late August · 1175 checklists that week, 34,453 in all4.5%
  4. Sagadahoc CountyBest mid September · 381 checklists that week, 21,736 in all4.4%
  5. Androscoggin CountyBest mid December · 154 checklists that week, 16,955 in all3.5%
  6. Cumberland CountyBest late August · 3830 checklists that week, 169,501 in all3.2%

Best spots

Share of checklists at the peak
  1. Acadia National Park (Champlain Mountain)Hancock County, best late June · 23 checklists that week, 300 in all92%
  2. Valley CoveHancock County, best early June · 50 checklists that week, 252 in all47%
  3. Monhegan IslandLincoln County, best the second week of October · 104 checklists that week, 4,434 in all44%
  4. Scarborough Marsh Wildlife Management Area (northeast)Cumberland County, best the second week of August · 32 checklists that week, 719 in all35%
  5. Goose River ReservoirWaldo County, best early January · 23 checklists that week, 308 in all28%
  6. Stratton IslandYork County, best early August · 26 checklists that week, 353 in all25%

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

Best time of day

In Maine, the Peregrine Falcon is most often listed on checklists started between 5 and 7 am (1.2% of those checklists).

0%0.5%1%1.5%12 am: too few checklists (510) to judge1 am: too few checklists (517) to judge2 am: too few checklists (581) to judge3 am: too few checklists (3242) to judge4 am: too few checklists (7221) to judge5 am: 0.7% of 19895 checklists6 am: 1.3% of 54578 checklists7 am: 0.9% of 92775 checklists8 am: 1.0% of 86962 checklists9 am: 1.1% of 78989 checklists10 am: 1.2% of 70954 checklists11 am: 1.1% of 59331 checklists12 pm: 1.0% of 50943 checklists1 pm: 1.0% of 49775 checklists2 pm: 1.0% of 49001 checklists3 pm: 1.1% of 43252 checklists4 pm: 0.9% of 33413 checklists5 pm: 0.9% of 25547 checklists6 pm: 0.8% of 18309 checklists7 pm: too few checklists (14287) to judge8 pm: too few checklists (5336) to judge9 pm: too few checklists (2253) to judge10 pm: too few checklists (1518) to judge11 pm: too few checklists (720) 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
January0.7%0.9%0.9%0.7%
February0.9%0.6%0.6%0.7%
March0.6%0.5%0.6%0.5%
April0.6%0.7%0.5%0.6%
May0.6%0.5%0.7%0.7%
June0.7%0.6%0.5%0.5%
July0.6%0.6%0.6%0.9%
August1.3%1.6%2.0%2.0%
September2.1%2.2%3.0%4.5%
October3.0%2.0%1.5%1.0%
November0.7%0.7%0.8%0.8%
December0.9%0.7%0.7%0.7%

Neighboring states

  • New Hampshire: arrives late February, 21 weeks earlier than Maine
  • Massachusetts: arrives the second week of July, 3 weeks earlier than Maine
  • Vermont: arrives mid February, 22 weeks earlier than Maine
  • Rhode Island: arrives mid July, 2 weeks earlier than Maine

Common questions

When do Peregrine Falcons arrive in Maine?
Peregrine Falcons arrive in Maine in early August, peak in late September (3.6% of checklists), and most are gone by late October.
When do Peregrine Falcons leave Maine?
Most Peregrine Falcons have left Maine by late October, when reports fall below half their usual rate.
When is the best time to see a Peregrine Falcon in Maine?
The Peregrine Falcon is reported most often in late September, on about 3.6% of Maine checklists.
Where in Maine are Peregrine Falcons seen most often?
By county, Lincoln County, York County, and Knox County have the highest peak reporting rates for the Peregrine Falcon (counties with at least 200 checklists).