Gould's Shipworm

Bankia gouldi

Gould's shipworm is a bivalve mollusk with:

• A long, worm-like body.
• Two small shells with toothed ridges on one end of the body.
• Two small siphons — one incurrent and one excurrent — and two hard, segmented pallets that look like stacks of tiny ice cream cones.

Shipworms grow to several inches long.

Where does Gould's shipworm live?

Shipworms can be found throughout the lower Bay and up into the brackish waters of the middle Bay.

• Shipworms live within calcified tunnels in untreated wood. The tunnels protect the shipworm's soft body.
• Shipworms use their boring shells to scrape away pieces of wood to form a tunnel.
• The end of each tunnel has a pinhole-sized entryway to the water. The shipworm's siphons stick out into the water through this hole.
• Each shipworm's tunnel never intersects with another, even if there are multiple tunnels in a single piece of wood.

What does Gould's shipworm eat?

Shipworms feed mainly on wood, but also eat planktonic particles brought in through their incurrent siphon.

How does Gould's shipworm reproduce?

Shipworms reproduce by releasing free-swimming veliger larvae into the water column.

• Larvae remain in the water column for two to three weeks before settling on any submerged untreated wood surface, such as pilings, ship planking and tree trunks or branches.
• The larvae use a small foot to move over the wood's surface and attach themselves with a secreted thread.
• Larvae use their tiny boring shells to drill and burrow into the wood, where they develop into adults.

Other facts about Gould's shipworm:

• Shipworms are not actually worms, but bivalve mollusks that are closely related to boring clams.
• As early as 412 B.C., mariners tried to protect their ships' hulls from shipworms using chemicals like sulphur and arsenic.
• White, porcelain-lined shipworm tunnels can often be seen in pieces of driftwood that wash ashore. They are about the width of a pencil and follow the grain of the wood.