It is native to the temperate northern Pacific and the central Indo-Pacific and is found in the intertidal zone and on submerged rocks, shells, pilings, jetties and boats.

The first dorsal pair of tentacles is unbranched and is modified to form a pseudoperculum, which can be used to close the tube after the worm has retracted inside.

It occurs in estuaries and bays, on hard substrates including rocks, seaweed, shells, pilings, docks, jetties, buoys and boats.

It is a common fouling organism of vessels, docks, industrial water intakes and aquaculture facilities, and sometimes grows on muddy gravel substrates.

Like all serpulids, H. ezoensis is a filter feeder, extending its crown of tentacles into the water column to catch plankton and organic particles floating past.