Best Time to See Dolphins in Massachusetts
August, November and December is the best time to see dolphins in Massachusetts. Based on 324 verified iNaturalist observations, here is exactly when dolphins are most active across the year in Massachusetts.
By Tim, founder of Easy Street Markets. I maintain the wildlife database and verify every animal and source myself. Updated June 28, 2026.
Atlantic White-sided Dolphin · Public domain CC0
Long-finned Pilot Whale · Lucy Keith-Diagne CC BY
Common Dolphin · Micki Colbeck CC BY
324 verified observations of dolphins in Massachusetts, recorded across 12 months of the year on iNaturalist.
When dolphins are recorded in Massachusetts
Peak month
August
51 records (15.7% of the year)
| Month | Observations | Share |
|---|---|---|
| January | 17 | 5.2% |
| February | 12 | 3.7% |
| March | 16 | 4.9% |
| April | 27 | 8.3% |
| May | 28 | 8.6% |
| June | 23 | 7.1% |
| July | 31 | 9.6% |
| Augustpeak | 51 | 15.7% |
| September | 24 | 7.4% |
| October | 26 | 8% |
| Novemberpeak | 37 | 11.4% |
| Decemberpeak | 32 | 9.9% |
Dolphins you are most likely to see
| Species | Verified observations |
|---|---|
| Common Dolphin | 149 |
| Atlantic White-sided Dolphin | 89 |
| Common Bottlenose Dolphin | 9 |
| Long-finned Pilot Whale | 9 |
| Risso's Dolphin | 3 |
| Tamanend's Bottlenose Dolphin | 2 |
| Short-finned Pilot Whale | 1 |
Weather to expect, source Open-Meteo
Typical weather in Massachusetts
Recent typical conditions by month, so you can plan a trip around both when dolphins are active and what the weather is doing. The best months to look for dolphins sit around 27 to 82 degrees Fahrenheit, so pack for that.
| Month | Avg high | Avg low | Rain |
|---|---|---|---|
| Jan | 37°F | 22°F | 3.8" |
| Feb | 39°F | 22°F | 3.4" |
| Mar | 48°F | 28°F | 3.6" |
| Apr | 57°F | 38°F | 4.6" |
| May | 68°F | 47°F | 3.4" |
| Jun | 78°F | 58°F | 3.6" |
| Jul | 83°F | 65°F | 5.4" |
| Augbest time | 82°F | 64°F | 3.5" |
| Sep | 73°F | 56°F | 5.3" |
| Oct | 62°F | 47°F | 5.3" |
| Novbest time | 50°F | 34°F | 3.1" |
| Decbest time | 42°F | 27°F | 5.9" |
Typical recent conditions (5-year means) from the Open-Meteo archive, averaged for Massachusetts. Weather varies year to year, so treat these as a guide.
Sightings of dolphins in Massachusetts peak in August, when 51 of the year's 324 verified observations are logged — about 15.7% of the annual total. Activity stays high through August, November and December.
The quietest stretch is February, March and January, when dolphins are hardest to find — February sees just 12 records. If a reliable sighting matters, plan around the peak window rather than the off-season.
The dolphins you are most likely to encounter in Massachusetts are Common Dolphin, Atlantic White-sided Dolphin and Common Bottlenose Dolphin — the most-recorded species in the state. Each keeps its own seasonal rhythm, but the month-by-month pattern above reflects every reported sighting together.
Where to go
Best places to see dolphins in Massachusetts
- Appalachian National Scenic Trail — National Scenic Trail
- Blackstone River Valley National Historical Park — National Historical Park
- Boston Harbor Islands National Recreation Area — National Recreation Area
- Cape Cod National Seashore — National Seashore
- Adams National Historical Park — National Historical Park
- Boston African American National Historic Site — National Historic Site
Frequently asked questions
What is the best month to see dolphins in Massachusetts?+
August is the single best month, and the broader peak window runs through August, November and December, based on 324 verified iNaturalist observations.
When are dolphins hardest to see in Massachusetts?+
February is the quietest month for dolphins in Massachusetts, with only 12 verified records.
Are dolphins active year-round in Massachusetts?+
Dolphins are recorded in 12 of 12 months in Massachusetts, so they can be seen year-round, with a clear peak in August.
More places to see dolphins
More wildlife in Massachusetts