Encrusting bryozoan, yellow/orange.
I'm not sure if this is a hydrocoral or a sponge. The surface is very hard.
About 1 cm. Was being eaten by a nudibranch (Doris montereyensis).
Basketball-sized colony at the edge of the fishing dock, another slightly smaller, and some smaller pieces of a colony that had been broken up by something.
Ubiquitous, attached to algae.
The Bryozoa, also known as Polyzoa, Ectoprocta or commonly as moss animals, are a phylum of aquatic invertebrate animals. Typically about 0.5 millimetres (0.020 in) long, they are filter feeders that sieve food particles out of the water using a retractable lophophore, a "crown" of tentacles lined with cilia. Most marine species live in tropical waters, but a few occur in oceanic trenches, and others are found in polar waters. One class lives only in a variety...