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Worms
By Gail Lu
Museum Student Staff

Slippery, slimy, creepy and crawly - these are just a few of the words that have been used to describe worms. Mysterious creatures found on land and in the sea, worms are all around us, living secretive and fascinating lives.

On land, one of the most common worms found in our local gardens is the common earthworm Lumbricus terrestris. It has been estimated that one acre of land contains about fifty thousand earthworms! Living underground in damp soil, earthworms tunnel and burrow, making it easier for air and water to penetrate . They also eat leaves and soil then leave behind castings which add nutrients that help plants grow. Earthworms keep the soil in good condition, and are food for many different kinds of animals , most notably, birds. Reaching lengths of about eight or nine inches here in the US, the common earthworm has a relative in Australia that can grow over ten feet long!

Another worm you might find in your garden is a flatworm by the name of Bipalium kewense. Native to Asia, this worm has been distributed around the world by the sale of tropical plants. B. kewense can reach lengths of up to 10 inches long, and is found in greenhouses and gardens in California and all over the United States. These worms are flat with light brown coloration, and five purple longitudinal stripes running along their dorsal side. B. kewense feeds on earthworms and reproduces asexually via a process called fragmentation. In this process, B. kewense pinches off and releases a small portion of its body which then grows and becomes another adult worm.

The fat inkeeper worm, Urechis caupo is an marine worm found in our local mud flats. Hidden in its U shaped burrow, the innkeeper worm gets its name from the other animals that inhabit its home. These guests include the reddish scale worm, the Pea Crab, and a goby. The inkeeper worm grows up to 20 inches long, but on average reaches lengths of 7 inches . It feeds by spinning a slime net about 2-8 inches long, which it attaches to the top of its burrow, and then pumps water through to catch microscopic food. When the net is full of food, the innkeeper worm then loosens the net from its attachments, moves up its burrow and swallows the net whole.

Another interesting marine worm is the scale worm Arctonoe vittata , which lives in a unique relationship with other animals. This relationship is called commensalism, in which the "guest" benefits from the living situation by obtaining protection and food, while the host remains unaffected. Found in the mid to low rocky intertidal, this scale worm is most commonly found living with the keyhole limpet, the gumboot chiton and the leather star. The worms body color often matches with their hosts, and in the case of the keyhole limpet, the worm may aid in protecting their hosts from predators.

These are just a few of the many species of worms that can be found locally. Next time you are gardening or tidepooling, be sure to keep an eye out for the worms around you. You'll be amazed at what you find!

For photos of local marine worms see our page on Other Tidepool Phyla: ... Annelida (Segmented worms)

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