WhenToBird

2 loon species in Massachusetts

When Do Loons Arrive in Massachusetts?

Adult Common Loon
Photo: Hungry-Sarracenia Photo, CC BY 4.0 via iNaturalist

Common Loons and Red-throated Loons are the loons you are most likely to see in Massachusetts. Common Loons are winter birds in Massachusetts: the first arrive in late September, they are common by mid October, peak in mid November (11% of checklists), and most are gone by late April.

When to look

First arrivalsSep 22-30late September
Common byOct 15-21mid October
PeakNov 15-21mid November
Most gone byApr 22-30late April

Best: mid November. First arrivals late September; most are gone by late April. Peak: on about 11% of Massachusetts checklists.

  1. Janpeak season
  2. Febpeak season
  3. Marpeak season
  4. Aprcommon
  5. Maycommon
  6. Jununcommon
  7. Juluncommon
  8. Auguncommon
  9. Sepuncommon
  10. Octpeak season
  11. Novpeak season
  12. Decpeak season

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

Loons in Massachusetts, species by species

SpeciesFirst arrivalsCommon byPeakMost gone byPeak %
Common LoonSep 22-30Oct 15-21Nov 15-21Apr 22-3011%
Red-throated LoonOct 15-21Oct 15-21Nov 15-21Apr 15-217.2%
0%5%10%15%Common LoonRed-throated LoonJanFebMarAprMayJunJulAugSepOctNovDec
  • Common Loon
  • Red-throated Loon
Share of complete checklists reporting each species, by week (4 per month). Gaps: fewer than 10 checklists that week.

Frequency is the share of complete checklists in Massachusetts 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.

Where in Massachusetts

Best counties for Common Loon

Share of checklists at the peak
  1. Essex CountyBest the second week of February · 4609 checklists that week, 213,973 in all30%
  2. Dukes CountyBest the second week of December · 302 checklists that week, 23,670 in all26%
  3. Barnstable CountyBest mid November · 3064 checklists that week, 215,188 in all22%
  4. Nantucket CountyBest mid December · 273 checklists that week, 23,895 in all19%
  5. Suffolk CountyBest early February · 1974 checklists that week, 112,443 in all16%
  6. Plymouth CountyBest mid November · 2140 checklists that week, 89,282 in all15%

Common questions

When do loons arrive in Massachusetts?
Common Loons are winter birds in Massachusetts: the first arrive in late September, they are common by mid October, peak in mid November (11% of checklists), and most are gone by late April.
When do loons leave Massachusetts?
Most Common Loons have left Massachusetts by late April, when reports fall below half their usual rate. Stragglers are still reported until late May.
When is the best time to see loons in Massachusetts?
The Common Loon is reported most often in mid November, on about 11% of Massachusetts checklists.
Which loons are in Massachusetts?
Common Loon and Red-throated Loon are reported regularly; the Common Loon is the most common.