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Native Freshwater Mussels


Mussel Morsels

Bullet. Freshwater mussels (also called clams) live for a very long time. In some species individuals commonly reach 50 years of age while in others individuals often reach 100! No centenarians live in the Rideau River, but they are found in other rivers in Canada.
Eastern lampmussel, Lampsilis radiata.
Eastern lampmussel, Lampsilis radiata (centre).
Bullet. Native freshwater mussels reach sexual maturity at ages ranging from 6 to 10 years.
Bullet. Because native freshwater mussels are not mobile, finding a mate can be difficult. Male mussels release sperm into the water, whence female mussels filter it for fertilizing their eggs.
Floaters attached to the fin of a fish.
Floaters (species of Pyganodon) encysted in the dorsal fin of a fish.
Bullet. Females brood the eggs until the larval stage, wherein the young are called glochidia. The glochidia encyst in the fish's tissue, where they are nourished and protected until they can live independently.
Bullet. For completion of the reproductive cycle native mussels require the help of a fish host. For some mussel species, only one fish species is suitable. For example, the eastern elliptio uses fish in the sunfish family as a host, the pocketbook uses largemouth bass, and the floater uses carp or white suckers. Some species of mussels even have an appendage that acts as a lure for the fish host.
Pearls a Danger to Mussels!
Did you know that your pearl necklace contains tiny pieces of freshwater mussels? The pearl industry discovered that a piece of freshwater mussel shell is a better "irritant" than a grain of sand in encouraging an oyster to create a pearl. This new threat to the survival of North American mussels led the United States to prohibit the possession of freshwater mussels for any purpose. [13]

North America: Mussels in Decline

Although they are particularly abundant in North America, native freshwater mussels are nevertheless threatened by the introduction of zebra mussels and the deterioration of their habitat.

In 2000, 213 of the 297 species of freshwater mussels native to North America were considered endangered, threatened or of special concern. [14] None of the Rideau River's mussel species is in these categories; even if survival in this River in particular is threatened by the presence of zebra mussels, the species live in many other rivers besides.

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 Native Mussels
 Don't Overlook...

Bags of mussels.
Mussels to go - ready for identifying by researchers, not for eating!

A Project of the Canadian Museum of Nature
 Images: Hemera, Jacqueline Madill, André Martel