Kelp Encrusting Bryozoan (Membranipora membranacea)

Description: Kelp encrusting bryozoans look like a thin, white crust often growing on kelp, but may also be found on rocks. The colony tends to be circular in shape with a bumpy texture to it. The circular colonies can get up to 20 cm across.

Habitat: As its name suggests, the kelp encrusting bryozoan is most frequently growing on kelp, but it can also live on other hard surfaces, like rocks. This bryozoan can be found in temperate zones worldwide. On our coast, it can be found from Alaska down to California from the low intertidal zone to depths of 180 m.

Diet: Kelp encrusting bryozoans are filter feeders like other bryozoans.

Tide Pool Tidbits: 

• The center of the colony is the oldest. The colony grows by separating a small part of an individual and using it as a base to start growing another individual. This process is called budding. For kelp encrusting bryozoans, this budding happens radiating outwards from the center, oldest individual.

• If the kelp that the colony is living on dies, the kelp encrusting bryozoan will die with it.

References: The New Beachcomber’s Guide to the Pacific Northwest by J Duane Sept, Walla Walla University, Friends of Netarts Bay