Biotic Interactions

Aside from capturing plankton for feeding, bryozoans exhibit biotic interactions of various kinds with other organisms. A wide variety of marine animal groups include bryozoans in their diets. Prominent among these are pycnogonids (sea spiders) and nudibranchs (sea slugs). Intramural buds are new zooids budded into the empty cystids of dead zooids. Common in many cheilostomes, they can be recognized by the presence of an additional mural or apertural rim located immediately within the original rim. The sessile nature of bryozoans means that they frequently form ‘incidental symbioses’ with a wide variety of other organisms in the broad sense of two different species living together permanently or semi‐permanently. Large bryozoan colonies form habitats for a wide variety of different animals at the present day. The interstices of large erect colonies are habitats for many animals seeking cryptic and hidden locations.