Cilia movements conduct food particles down toward the mouth. The name's origin is probably because they look like a bird's beak. Normally avicularia adopt an open 'beak' but sometimes the beak is quickly closed, maybe when an object touches a tuft of hairs located in the middle. Yet bugulas tolerate well any vorticellas or suctorias that are present. The picture left shows an avicularian on a Bugula species.
Reproduction gives rise to rounded ovicells, called ooecia.
Often you can see a single egg in each ooecium. See the picture below which also shows free swimming ciliated larva. When the colony becomes older, some individuals near the stalk base, contract and only ovoid brown masses can be seen inside the stall. Ooecium and larva. One specimen I found was more than 80 cm long.