A New Look for Oysters

Identifying affected oysters requires shucking the oyster, often you cannot tell from the outside.

It is unlikely that you will find P. websteri itself, you are most likely to find the home it made inside the oyster's shell, or the remaining scar. The meat of the oyster is usually untouched, but the animal instead burrows into the shell of the oyster leaving a scar or a small amount of mud.

If you were to find P. websteri in an oyster, it would be fairly small, ~1mm wide and 20mm in length.

Clements, J. C., Bourque, D., McLaughlin, J., Stephenson, M., & Comeau, L. A. (2018). Wanted dead or alive: Polydora websteri recruit to both live oysters and empty shells of the eastern oyster, Crassostrea virginica. Journal of Fish Diseases, 41(5), 855–858. https://doi.org/10.1111/jfd.12794

Considine, M., Martinelli, J., King, T., Hauser, L., Padilla-Gamiño, J., Rumrill, S., Wood, C. (2020). Mudblister Worm, Polydora websteri, in Pacific Oysters: Identification, Distribution, and Mitigation Strategies[PowerPoint slides].

Discover Life. (n.d.). Polydora websteri Hartman, 1943. Discover Life. Retrieved November 20, 2020, from https://www.discoverlife.org/mp/20q?search=Polydora+websteri

Pacific Shellfish Institute. (2013). Learn more about shellfish in your area. Retried November 20, 2020 from http://www.pacshell.org/oregon.asp

Martinelli, J.C., Lopes, H.M., Hauser, L. et al. Confirmation of the shell-boring oyster parasite Polydora websteri (Polychaeta: Spionidae) in Washington State, USA. Sci Rep 10, 3961 (2020). https://doi.org/10.1038/s41598-020-60805-w

Morse, D. L., Rawson, P. D., & Kraeuter, J. N. (2015). Mud blister worms and oyster aquaculture.

Shell Recycling. (2017). Retrieved from https://oysterrecovery.org/sra/

Rice, L., Lindsay, S., Rawson, P., 2018. Genetic homogeneity among geographically distant populations of the blister worm Polydora websteri. Aquaculture Environment Interactions.. doi:10.3354/aei00281

Waser, A.M., Lackschewitz, D., Knol, J. et al. Spread of the invasive shell-boring annelid Polydora websteri (Polychaeta, Spionidae) into naturalised oyster reefs in the European Wadden Sea. Mar. Biodivers. 50, 63 (2020). https://doi.org/10.1007/s12526-020-01092-6