Jellyfishes in California in July

Yes, July is one of the best months to see jellyfishes in California. It is the 2nd busiest month of the year, with 1,230 of the 8,243 sightings logged across the year (14.9%), based on verified iNaturalist records.

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By Tim, founder of Easy Street Markets. I maintain the wildlife database and verify every animal and source myself. Updated June 28, 2026.

Black Jelly photographed in CaliforniaBumpy Jelly photographed in CaliforniaAustralian Spotted Jelly photographed in California
Photos by iNaturalist observers, used under Creative Commons.

Peak month for jellyfishes in California

14.9%

of yearly sightings

1,230

records in July

#2

busiest month of 12

8,243

verified records a year

June 9.3%, July 14.9%, August 15.8%. Busiest month is August at 15.8%.

Best months: August, July, SeptemberPeak season right now

8,243 verified observations of jellyfishes in California, recorded across 12 months of the year on iNaturalist.

When jellyfishes are recorded in California

Peak month

August

1,300 records (15.8% of the year)

Quietest month

January

314 records

MonthObservationsShare
January3143.8%
February3233.9%
March3984.8%
April5136.2%
May6377.7%
June7639.3%
Julypeak1,23014.9%
Augustpeak1,30015.8%
Septemberpeak1,19414.5%
October6788.2%
November4805.8%
December4135%

Jellyfishes you are most likely to see

SpeciesVerified observations
Greater Moon Jelly2,628
Pacific Sea Nettle2,389
Purple-striped Sea Nettle848
Egg-yolk Jelly538
Asian moon jellyfish175
Australian Spotted Jelly26
Black Jelly13
Pacific Lion's Mane Jelly3

In California, July carries 14.9% of the year's jellyfishes sightings, about 6.6 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 June (9.3%) into July, and it heads toward August (15.8%) after. This is right inside the peak window, so July is one of the surest months to plan a trip around.

The jellyfishes most often recorded in California are Greater Moon Jelly, Pacific Sea Nettle and Purple-striped Sea Nettle. Those counts are annual totals rather than a July split, so treat them as which species you are likely to encounter, while the month figures above show how many sightings fall in July itself.

Which jellyfishes you are most likely to see

  • Greater Moon Jelly2,628 records
  • Pacific Sea Nettle2,389 records
  • Purple-striped Sea Nettle848 records
  • Egg-yolk Jelly538 records
  • Asian moon jellyfish175 records
  • Australian Spotted Jelly26 records
Plan your tripAlcatraz Island

Plan your jellyfish trip in California

Start with live tours near Alcatraz Island, then compare a nearby stay and a broader wildlife backup before you lock in the trip.

Frequently asked questions

Can you see jellyfishes in California in July?+

Yes. July accounts for 1,230 of the 8,243 verified jellyfishes sightings logged in California across the year, which is 14.9% of the annual total.

Is July a good time to see jellyfishes in California?+

July is one of the best months. It ranks 2nd of the year and sits inside the peak window of August, July and September.

What month is best for jellyfishes in California?+

August is the single busiest month, with the broader peak running through August, July and September, based on 8,243 verified observations.

Which jellyfishes are you most likely to see in California?+

The most-recorded species in California are Greater Moon Jelly, Pacific Sea Nettle and Purple-striped Sea Nettle, based on all-time iNaturalist counts.