68 Scientific American, May 2022
Jovelle Tamayoexample, is famous for producing Pacific oysters with
pearly, unblemished shells. But in 2017 a colleague
dropped a shell on Wood’s desk marked with squig-
gly canals and dark, ugly spots—signs of a shell-bor-
ing oyster pest called Polydora. Although the para-
sites themselves are not dangerous for people to con-
sume, they form blisters on the oyster shells filled
with mud and worm feces and scar them with their
voracious tunneling. It’s not something diners wanton their plates. Since the 1860s Polydora outbreaks
have devastated oyster industries in Australia, Hawaii
and the U.S. East Coast, but Washington State—the
U.S.’s largest producer of farmed bivalves—had long
been spared. In March 2020, however, Julieta Marti-
nelli, one of Wood’s postdocs, and her colleagues
wrote in the journal Scientific Reports that one noto-
rious species, Polydora websteri, had indeed invaded
the Puget Sound.TO SEE whether
parasite popula
tions have changed
over time, the
Wood Lab dissects
walleye pollock
ranging from
four to 116 years
old in search of
parasitic worms
and arthropods.