Story: Open ocean

Jellyfish life cycle

Jellyfish life cycle

Jellyfish have a stalked (polyp) phase, when they are attached to coastal reefs, and a jellyfish (medusa) phase, when they float among the plankton. The medusa is the reproductive stage; their eggs are fertilised internally and develop into free-swimming planula larvae. After a brief period floating about in surface waters, the larvae settle to the sea floor, attaching themselves at one end. There they develop into polyps and begin to feed and grow. In spring, some of the polyps start to bud off immature jellyfish known as ephyra larvae. These grow into mature jellyfish.

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Te Ara - The Encyclopedia of New Zealand
Artwork by Bruce Mahalski

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How to cite this page:

Janet Grieve, 'Open ocean - Larger plankton in the food chain', Te Ara - the Encyclopedia of New Zealand, (accessed 16 June 2024)

Story by Janet Grieve, published 12 Jun 2006