What is a “Moon Jellyfish”?

30 December 2014

The Short Answer (TSA)

            Known as the “Moon Jellyfish” or “Moon Jelly” to its friends, the formal name of this creature is “Aurelia aurita.”   Why “Moon” Jellyfish?  It gets its "moon" name because of its white color and circular shape.  Well, it’s not exactly snow white.  But it's as white as a jellyfish can get.  Jellyfish are translucent, you can see through them.  So, the Moon Jellyfish at least has a white “tint.”

            The Moon Jelly measures between 10 and 16 inches in diameter.  This jellyfish eats plankton and mollusks it picks up on the sea floor.   It really can’t chase its prey because Moon Jellies aren’t just slow-moving, they’re also extremely weak swimmers.  They depend on the tidal currents to move them along. 

            Moon Jellies are found in about every ocean on earth.  They live comfortably in warm tropical waters as well as the waters just off the coastal areas of Northern Europe, New England, and Eastern Canada.

  

            The Moon Jelly lives only in salt water.  While it tolerates warmer and colder temperatures, it seems to like its water between 48 and 66 degrees F.  Also, because of its modest swimming abilities, it favors seas that consistently have a current on which the Moon Jelly depends to keep it moving.

            Moon Jellies only live for about 6 months in the wild.  And they have their share of natural enemies.  Considered a taste treat by many sea birds, the Leatherback Sea Turtle and Ocean Sunfish also consider the Moon Jelly a “good dinner guest.”  

Mark Grossmann of Hazelwood, Missouri & Belleville, Illinois

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