Freshwater Mussels Pacific Northwest - The Xerces Society

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Life History and Habitat
A. oregonensis and A. kennerlyi inhabit
low gradient rivers, lakes,
and reservoirs. They often share
habitat with A. californiensis
where their ranges overlap. Like
other Anodonta, they are likely
long-term brooders that breed
in the summer and spawn in the
fall or spring. In lake populations
of A. kennerlyi, gravid females
were observed from late summer
to the following spring, and glochidia
were found on fish from fall
through the spring but peaked in
Range of Anodonta
Clade 2 in western
North America
the spring 60 . Very little is known about host fish relationships. Coho salmon
have been identified as hosts for the Oregon floater 65 . In lakes on Vancouver
Island, British Columbia, glochidia of A. kennerlyi were found on all fish species
examined (four species) but prickly sculpin and three-spine stickleback
were more important hosts than the two trout species (Dolly Varden trout
and cutthroat trout), possibly because the sculpin and stickleback were more
prevalent in areas of the lakes were mussels were concentrated 60 .
Conservation
This clade is likely affected by the same factors that affect other western Anodonta,
including water diversion, dams, loss of host fish species, pollution,
and invasive species. Since A. kennerlyi is distributed in less-disturbed northern
areas, it has probably not experienced the full range of stressors experienced
by more southern and coastal Anodonta. Thorough surveys are needed
to determine the current distribution of this clade, although the authors are
not aware of any evidence that suggests this clade is in decline.
Freshwater Mussels of the Pacific Northwest