An initiative of Earthwatch Institute

  1. Moon_jelly_g_edgar Moon Jelly by G. Edgar
  2. Aurelia_aurita_-_david_ford Moon Jellies washed onshore by D Ford

Moon Jelly

Aurelia aurita


  • Moon jellies have a transparent mushroom shaped bell.
  • Its reproductive organs form a conspicuous clover-like shape when viewed from above. 
  • Numerous fine thread-like tentacles hang from beneath edge of the bell. 
  • Size: up to 40 cm (bell diameter)

What to Observe

Search area for 30 minutes and record under the following categories:

  • Abundant - found easily with little searching
  • Frequent - found with minimal searching
  • Rare -  only 1 or 2 individuals found with intensive searching
  • Not found - not present during search

ClimateWatch Science Advisor

Changing ocean currents and productivity, as a result of climate change, may lead to an increase in jelly fish abundance (which may result in detrimental impacts on fishing and coastal industries). In other locations, a change in conditions may result in a reduction of jelly fish numbers.  

When To Look

Throughout the year.


The map below displays the accumulated observations of these species as reported by ClimateWatch observers, together with the layer showing how the range of the species might change between now and 2085, with orange areas indicating where the species might disappear, and green areas where the species range might expand.

  1. Search Species

  1. What Else?

    The spotted jelly (Phyllorhiza punctate) is similar in size, shape and transparency to the moon jelly but can be distinguished by the presence of many small spots in its bell.  

  1. Did You Know?

    The moon jelly is a favourite food of marine turtles.