Anyone who pokes about the rocky seashore is familiar with Zebra Blennies. They live in pools at or above the high tide line, generally along turbulent shores where basalt rock predominates. A small pool will sometimes support dozens of blennies, especially if there is ample shelter in the form of large boulders under which they can retreat. Their bodies vary from smart blue-black to charcoal or brownish gray with indistinct bars (hence the name). They become mottled when feeding in shallow water or when alarmed. Adults have a row of tiny bright blue spots under the eye. A crest and two tentacles (longer in males) adorn the head, but collapse entirely when out of the water. Zebra Blennies feed almost entirely on organic detritus that accumulates on the rocky sides and bottoms of their pools. They adapt well to the aquarium and make fun, alert pets that are unusually tolerant of temperature and salinity changes. If you keep one or more of these fish, be sure their tank is well covered. They grow to about 7 in. and are endemic to the Hawaiian IslandsThe Blenny Family is commonly confused with the Goby family. The Blennies are distinguished by their single continuous dorsal fin and habit of resting on the bottom with their body curved. These fish will usually have tiny appendages on the top of their heads called "cirri". Some Blennies inhabit tidal pools where the water is warm and shallow. They have incredible jumping ability and are known to jump from pool to pool, which lends to the other name they are known as: "Rock Skipper". Other Blennies are found hiding in crevices and caves at coral reefs. These fish have blunt heads and their teeth are combed, giving them the ability to scrape algae -- their primary food source -- from rock surfaces.
Hawaiian Zebra Blenny