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Bryozoans are minute colonial animals, with individual members of the colony called zooids.


Lace corals and sea mats - Bryozoa

Bryozoans are minute colonial animals. Individual members of the colony are called zooids, which come in a huge variety of shapes, colours and arrangements. Some colonies form intricate and spectacular patterns. The zooids are usually about 1 mm long and are often rectangular or box-shaped. The sides of each zooid have numerous holes that allow them to connect to the rest of the colony. They have no excretory organs and no blood circulation system but usually have tiny tentacles surrounding a mouth-like opening.

Bryozoan facts:

  • There are around 6,600 species of bryozoans worldwide.
  • About 210 species are known to occur in Sydney Harbour.
  • Most coastal waters will have bryozoans present all year round.
  • Bryozoans are also found in rock pools.