Biology/Natural History: Lives in an L-shaped burrow, head down. It everts its esophagus then pulls it in, thus ingesting mud and feeding on organisms such as nematodes within it. Periodically it backs up to near the surface to defecate, forming the characteristic mound around its burrow. The mound will often have coils of castings roughly 1/2 cm in diameter. The lugworm pulses its body while within the burrow to bring in oxygenated water.