Under Threat - The Dwarf Wedgemussel

The Dwarf Wedgemussel is a small-sized and rare species of freshwater mussel that is only found inhabiting the streams and rivers along North America's Atlantic Coast. Although the range of the Dwarf Wedgemussel would have once extended north into Canada, they have been extinct there since the late 1960s.

The Dwarf Wedgemussel is a tiny creature that only rarely grows to more than four and a half centimetres in size, making this rare animal even harder to spot amongst the pebbly sand on the riverbed. They are most commonly found in small streams and deep rivers where they prefer to bury themselves in the clay amongst the roots of trees in the water.

Living for a maximum of 12 years, the Dwarf Wedgemussel is not a long-lived freshwater mussel species. It also relies on the need for a host fish in order to reproduce, as with a number of other similar species their larvae feeds off the host fish as a parasite until it is old enough and using metamorphosis, turns into it's independent, young mussel form.

Despite being incredibly small, the Dwarf Wedgemussel is one of the most threatened of it's kind in North America and is today considered to be an Endangered animal species by the IUCN. The Dwarf Wedgemussel is also protected by law in the majority of it's natural range but populations are still declining and are becoming more separated from one another.

Like other mussel species, the Dwarf Wedgemussel obtains the nutrients that it needs to survive by taking water into it's shell and filtering the nutritious particles out of it. They are therefore severely threatened by increasing levels of pollution in the water, particularly from chemicals that are used in agriculture.