Worms and Sponges

Segmented marine worms are easily identified by the many visible rings that make up their bodies. Over 9,000 species of segmented worms have been identified. Many marine species are found on the sea bottom but are not restricted to it. Sponges are filter-feeding, colonial animals which live together as a larger unit. They appear to be plants but are in fact invertebrate animals. Unique to the animal world, sponges have canals throughout their bodies which open to the surrounding water, allowing both oxygen and food particles to reach each sponge.
Feather duster worm

feather duster worm

Eudistylia vancouveri

Description: These marine worms are relatives of segmented land worms. This species secretes a leathery tube. Feathery cirri banded with colors of maroon, blue and green. Cirri have eye-spots sensitive to light and shadow. Found in colonies on pilings, rocky crevices, and subtidally in large masses on the beaches of Edmonds. Storms and strong currents sometimes break loose clusters of worms and wash them onto shore, as pictured at left. Length to 10 in (25 cm).

Food: Feathery tentacles called "cirri" trap plankton. Tiny cilia on the plumes carry the food to the mouth.

Reproduction: Eggs laid.

Fun Facts: At low tide one can gently touch (with wet finger) the cirri and watch the startled worm withdraw rapidly into its tube.

Calcereous tube worm

calcareous tube worm

Serpula vermicularis

Description: These marine worms are relatives of segmented land worms. This species secretes a hard calcareous tube. Feathery cirri are red. Cirri have eye-spots sensitive to light and shadow. Common under intertidal rocks, on shells and pilings. Length to 4 in (10 cm).

Food: Feathery tentacles called "cirri" trap plankton. Tiny cilia on the plumes carry the food to the mouth.

Reproduction: Eggs laid.

Fun Facts: The shell of this worm is made of calcium carbonate.

Ruffled scale worm

ruffled scale worm

Arctonoe fragilis

Description: Often found living commensally (living with, on, or in another, without injury to either) on mottled sea stars. Light or dark in color, often matching color of host. Length up to 3 in (8 cm).

Food: These worms eat the scraps and detritus left over from the sea star's meals, as well as clean the sea star's tube feet of debris, giving them the nickname "sea star toothbrushes."

Reproduction: Eggs laid.

Fun Facts: The worm pictured above came off of a blue mottled sea star, and was returned to its host after the photo was taken.

Bread crumb sponge

bread crumb sponge

Halichondria panicea

Description: The most primitive of multi-celled animals, with no specialized tissue and no blood. This is a soft encrusting sponge. Tan to yellow in color, with a bread-like texture.

Food: Microscopic cilia create a current that brings plankton into the pores on the sponge's surface. Plankton are filtered out for food.

Reproduction: Cellular division.

Fun Facts: Smells like gun powder when broken.

Red encrusting sponge

red encrusting sponge

Ophlitaspongia pennata

Description: The most primitive of multi-celled animals, with no specialized tissue and no blood. This is a soft encrusting sponge, red to orange in color. It has a smooth texture punctuated by numerous tiny pores. Common on intertidal rocks; prefers strong wave action. Locally, easiest to find under the ferry dock.

Food: Microscopic cilia create a current that brings plankton into the pores on the sponge's surface. Plankton are filtered out for food.

Reproduction: Cellular division.

Fun Facts: This sponge is eaten by a very small red nudibranch which matches its color perfectly.