US: WA oyster farmers monitor potential mud worm problem

Researchers have officially confirmed the presence of a shell-boring oyster parasite Polydora websteri, also known as mud worm, on the shells of Pacific oysters in Washington State. And while the industry says it is not on a level that causes concern, it is keeping a watchful eye. The study, “Confirmation of the shell-boring oyster parasite Polydora websteri (Polychaeta: Spionidae) in Washington State, USA,” published in 2020, is the first confirmed record of the species in the state. Researchers Martinelli, J.C., Lopes, H.M., Hauser, L. et al, said the invader has led to significant economic losses for shellfish aquaculture in Australia, New Zealand, and Hawaii. David Beugli, executive director of The Willapa Grays Harbor Growers Association in Southwest Washington, says mud worm may have occurred in low numbers for some time. “The blister discolors the shell but has no effect on the meat. Currently they have not caused a problem here and are not a concern.” He acknowledged, ...