Jellyfishes in Massachusetts in May
Yes, May is one of the best months to see jellyfishes in Massachusetts. It is the 2nd busiest month of the year, with 419 of the 1,950 sightings logged across the year (21.5%), based on verified iNaturalist records.
By Tim, founder of Easy Street Markets. I maintain the wildlife database and verify every animal and source myself. Updated June 28, 2026.
Peak month for jellyfishes in Massachusetts
21.5%
of yearly sightings
419
records in May
#2
busiest month of 12
1,950
verified records a year
April 11.6%, May 21.5%, June 24.2%. Busiest month is June at 24.2%.
1,950 verified observations of jellyfishes in Massachusetts, recorded across 12 months of the year on iNaturalist.
When jellyfishes are recorded in Massachusetts
Peak month
June
471 records (24.2% of the year)
| Month | Observations | Share |
|---|---|---|
| January | 4 | 0.2% |
| February | 6 | 0.3% |
| March | 52 | 2.7% |
| April | 227 | 11.6% |
| Maypeak | 419 | 21.5% |
| Junepeak | 471 | 24.2% |
| July | 207 | 10.6% |
| Augustpeak | 295 | 15.1% |
| September | 178 | 9.1% |
| October | 83 | 4.3% |
| November | 5 | 0.3% |
| December | 3 | 0.2% |
Jellyfishes you are most likely to see
| Species | Verified observations |
|---|---|
| Atlantic Lion's Mane Jelly | 610 |
| Common Moon Jelly | 174 |
| Bay Nettle | 169 |
| Atlantic Sea Nettle | 45 |
| Dwarf Lion's Mane Jelly | 32 |
| Mauve Stinger | 31 |
| Lion's Mane Jelly | 10 |
| Southern Moon Jelly | 8 |
In Massachusetts, May carries 21.5% of the year's jellyfishes sightings, about 13.2 points above an even month-to-month split. That makes it the 2nd busiest of the twelve months, out of 12 months with recorded activity.
Activity is rising from April (11.6%) into May, and it heads toward June (24.2%) after. This is right inside the peak window, so May is one of the surest months to plan a trip around.
The jellyfishes most often recorded in Massachusetts are Atlantic Lion's Mane Jelly, Common Moon Jelly and Bay Nettle. Those counts are annual totals rather than a May split, so treat them as which species you are likely to encounter, while the month figures above show how many sightings fall in May itself.
Which jellyfishes you are most likely to see
- Atlantic Lion's Mane Jelly610 records
- Common Moon Jelly174 records
- Bay Nettle169 records
- Atlantic Sea Nettle45 records
- Dwarf Lion's Mane Jelly32 records
- Mauve Stinger31 records
Plan your jellyfish trip in Massachusetts
Start with live tours near Appalachian National Scenic Trail, then compare a nearby stay and a broader wildlife backup before you lock in the trip.
GetYourGuide
Live tours nearbySee live tours near Appalachian National Scenic Trail
Use the live GetYourGuide widget to compare local departures and activity styles close to the main jellyfish viewing area.
Booking.com
Stay nearbyStay near Appalachian National Scenic Trail
Compare hotels, cabins and lodges close to the best jellyfish viewing area in Massachusetts.
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Broader backupBook a jellyfish tour in Massachusetts
Compare guided wildlife tours, boat trips and nature experiences if you want a second travel network beyond the live widget.
Frequently asked questions
Can you see jellyfishes in Massachusetts in May?+
Yes. May accounts for 419 of the 1,950 verified jellyfishes sightings logged in Massachusetts across the year, which is 21.5% of the annual total.
Is May a good time to see jellyfishes in Massachusetts?+
May is one of the best months. It ranks 2nd of the year and sits inside the peak window of June, May and August.
What month is best for jellyfishes in Massachusetts?+
June is the single busiest month, with the broader peak running through June, May and August, based on 1,950 verified observations.
Which jellyfishes are you most likely to see in Massachusetts?+
The most-recorded species in Massachusetts are Atlantic Lion's Mane Jelly, Common Moon Jelly and Bay Nettle, based on all-time iNaturalist counts.
See jellyfishes in Massachusetts in other months
More wildlife in Massachusetts