Moon Jellyfish (Aurelia Aurita)

CleopatraPembrokeshire

Most clients we take out Coasteering have an understandable fear of jellyfish. So I thought I’d give you an introduction to this beautiful creature. All jellyfish sting, however the moon jellies stinging tentacles cannot get through our skin (it’s too thick).

The Medusa is translucent, usually about 5-40 cm across, and can be recognized by its four horseshoe-shaped gonads (like craters on the moon) that are easily seen through the top of the bell.

It feeds by collecting medusae, plankton and mollusks with its mucusy bell tentacles and bringing the prey into its body for digestion, but is capable of only limited motion; like other jellies it primarily drifts with the current even when it is swimming.

During calmer sea conditions we often come across them in sheltered bays, inlets etc.
Often found washed up on the beach, they are not dead as the rising tide will take them back out to sea. Jellyfish have no gills/lungs etc but absorb oxygen through diffusion.

Moon Jelly’s are found along the eastern Atlantic coast of Northern Europe and the western Atlantic coast of North America in New England and Eastern Canada.

Found in estuaries and harbours, they live in ocean water temperatures of -6’C to 31’C, with optimum temperatures of 9’C to 19’C. This is probably why we see so many of them in the summer months when the sea temp in warming up.

Moon jellyfish are known to be eaten by a wide variety of predators including the , the Leatherback Sea Turtle, other large jellyfish and sea birds.

Aurelia jellyfish naturally die after living and reproducing for several months. It is probably rare for these moon jellies to live more than about six months in the wild, although specimens cared for in public aquarium exhibits typically live several to many years.
Why not come and meet these beautiful creatures face to face?