Status and Life History Traits of Simpsonaias ambigua (Salamander Mussel) in Ontario, Canada

Simpsonaias ambigua (Salamander Mussel) is a freshwater mussel of the Family Unionidae endemic to North America, and it is considered endangered across most of its range. This species is unique among the Unionidae, because it uses the salamander, Necturus maculosus (Mudpuppy), as its larval host rather than fish like all other unionids. The overall goal of this study was to obtain baseline data on the current distribution and life history traits of S. ambigua in Ontario, Canada. These data are critical for future recovery efforts to protect, restore, or augment populations of S. ambigua across its range. Conventional survey methods were adapted to target S. ambigua, and an additional method was employed to detect this species: trapping N. maculosus and inspecting for signs of encysted glochidia. Both methods were successful at detecting S. ambigua when they were present. Furthermore, Simpsonaias ambigua’s life history traits were investigated, and more information is now available on the reproductive timing windows related to gonad and glochidia development and the host infestation period, as well as on longevity.