Last fall, freshwater mussels were reintroduced to the Mill Creek at two locations. These were the first mussels in Mill Creek for over 100 years.....we thought. At our first ever Mill Creek BioBlitz at Salway Park on June 1, a volunteer found a mussel shell at the upstream riffle we installed in 2018. The mussel has now been positively identified: it is a recent shell of a female fatmucket, also known as a yellow mucket. Although the species is widespread in the state, this is the first record of this species in the Mill Creek. It means it is quite likely that there are other mussels in the stream, at least below Salway. Larval mussels (glochidia) spread by attaching to the gills of fish, then later dropping off. By opening up more of the stream to fish migration, it’s open for mussel migration also.