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Jellyfish

Moon Jellyfish

Aurelia aurita

Aurelia aurita (Linnaeus, 1758) · Ulmaridae WoRMS 135306

Reference photos

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Britain's commonest jellyfish. A smooth, flattened, translucent saucer of a bell, colourless except for four horseshoe-shaped gonad rings showing through the middle in mauve, violet or pink, with a fringe of numerous short tentacles round the rim. Those tentacles are ringed with stinging cells, and the species does sting swimmers.

Depth

Coastal and pelagic, in the upper epipelagic near the surface, with records down into the mesopelagic (200 to 1,000 m)

Size

Bell usually about 25 cm across and up to 40 cm

Habitat

Pelagic in coastal seas, also running up estuaries and into harbours, and especially common in Scottish sea lochs

Behaviour

Sporadic in appearance, at times swarming densely enough to colour the sea and slow a small boat

Diet

I eat

  • Plankton, including copepods and other small drifting animals
  • Fish eggs, small molluscs and smaller jellyfish
  • A generalist that takes whatever small prey it meets, caught on contact rather than chased down

Eats me

  • Herring and whiting, the most frequent jellyfish eaters found in an Irish Sea stomach-content study
  • Dab and squid, with dragonet and grey gurnard also recorded as occasional jellyfish eaters
  • Leatherback turtles and sunfish, and other jellyfish

Where you'd find it

Found around most of Britain and Ireland, though less often in the waters west of Ireland.

ChannelCeltic SeaNorth SeaIrish SeaW of IrelandW of Scotland
Often seenNow and thenWhere PEBL filmsBased on marine survey records (OBIS). Blank seas can mean nobody has looked there, not that the animal is absent.

Sources

Open-access references behind this page. Every statement on this page was read out of one of them; anything that could not be traced to a source was taken off the page rather than left standing. Each link was checked on the date shown, and confirmed then to be about this species.

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