Bay Mussel - Mytilus trossulus
Bay Mussels are common bivalves found in the middle intertidal along coastal British Columbia. The elevation that they are found is limited by dessication at the upper end and predation by seastars at the lower end.
The common name mussel is used for members of several different families of clams or bivalve molluscs, from both saltwater and freshwater habitats. The one thing that these different groups have in common, is that they have a shell whose outline is somewhat elongated and asymmetrical compared with that of many other edible clams, the shells of which are often more or less rounded or oval in shape.
The word "mussel" is most frequently used to mean the edible bivalves of the marine family Mytilidae, most of which live on exposed shores in the intertidal zone, attached by means of their strong byssal threads ("beard") to a firm substrate. A few species (in the genus Bathymodiolus) have colonized hydrothermal vents associated with deep ocean ridges.
In most marine mussels the shell is longer than it is wide, being wedge-shaped or asymmetrical. The external color of the shell is often dark blue, blackish, or brown, while the interior is silvery and somewhat nacreous.
The freshwater Zebra mussels and their relatives in the family Dreissenidae are not related to either of the previously mentioned groups, even though they resemble many Mytilus species in shape, and live attached to rocks and other hard surfaces in a similar manner, using a byssus. They are classified with the Heterodonta, the taxonomic group which includes most of the bivalves commonly referred to as "clams".
Common Names
Bay Mussel
Phylum
Mollusca
Class
Bivalvia
Family
Mytilidae
Elevations
Middle intertidal. Elevation limited by seastar populations at lower intertidal and dessication at upper intertidal.
Distribution
Temperate waters around the world.
Community
Saline environments with enough current to support bivalves. More common in bays and estuaries, and occasionally on the outer coast.
Substrate
Rocks, docks, pilings, floats and gravel.
Attachment
It attaches to the substrate with its many fine, tough, byssal threads.
Size
6 to 10 cm long, 3 to 5 high.
Description
Shiny blue-black to black or brownish; shell has a long rounded triangular shape.
Wave-Exposure
High Tolerance
Habitat Significance
Provide a source of food for many marine organisms including sea stars, birds, and fish. The tangled mass of mussels and byssus forms homes for numerous small creatures.
Mistaken Identity
Mytilus edulis, or the Blue Mussel, is only found on the Atlantic. It is easily mistaken for the Bay Mussel in apperance with the exception that it is black instead of blue.
Typical Abundance
Grows into thick, dense clumps.
Protection
While the Bay Mussel does provide an abundant food source for many organisms, it is very common along coastal British Columbia and therefore is not critical habitat. However, it is still important habitat and areas lost are usually made up for by placement of additional rock in the intertidal.
Balanced Environmental Services Inc. does not authorize the reproduction of any images, documents or other information contained within. The environmental consulting information provided does not necessary reflect the views of those parties identified. Any copying in part or in whole of any of the information presented on this site is strictly prohibited without the written consent of Balanced Environmetnal Services Inc.
Employee Login
Bay Mussels are common bivalves found in the middle intertidal along coastal British Columbia. The elevation that they are found is limited by dessication at the upper end and predation by seastars at the lower end.
The common name mussel is used for members of several different families of clams or bivalve molluscs, from both saltwater and freshwater habitats. The one thing that these different groups have in common, is that they have a shell whose outline is somewhat elongated and asymmetrical compared with that of many other edible clams, the shells of which are often more or less rounded or oval in shape.
The word "mussel" is most frequently used to mean the edible bivalves of the marine family Mytilidae, most of which live on exposed shores in the intertidal zone, attached by means of their strong byssal threads ("beard") to a firm substrate. A few species (in the genus Bathymodiolus) have colonized hydrothermal vents associated with deep ocean ridges.
In most marine mussels the shell is longer than it is wide, being wedge-shaped or asymmetrical. The external color of the shell is often dark blue, blackish, or brown, while the interior is silvery and somewhat nacreous.
The freshwater Zebra mussels and their relatives in the family Dreissenidae are not related to either of the previously mentioned groups, even though they resemble many Mytilus species in shape, and live attached to rocks and other hard surfaces in a similar manner, using a byssus. They are classified with the Heterodonta, the taxonomic group which includes most of the bivalves commonly referred to as "clams".
Common Names
Bay Mussel
Phylum
Mollusca
Class
Bivalvia
Family
Mytilidae
Elevations
Middle intertidal. Elevation limited by seastar populations at lower intertidal and dessication at upper intertidal.
Distribution
Temperate waters around the world.
Community
Saline environments with enough current to support bivalves. More common in bays and estuaries, and occasionally on the outer coast.
Substrate
Rocks, docks, pilings, floats and gravel.
Attachment
It attaches to the substrate with its many fine, tough, byssal threads.
Size
6 to 10 cm long, 3 to 5 high.
Description
Shiny blue-black to black or brownish; shell has a long rounded triangular shape.
Wave-Exposure
High Tolerance
Habitat Significance
Provide a source of food for many marine organisms including sea stars, birds, and fish. The tangled mass of mussels and byssus forms homes for numerous small creatures.
Mistaken Identity
Mytilus edulis, or the Blue Mussel, is only found on the Atlantic. It is easily mistaken for the Bay Mussel in apperance with the exception that it is black instead of blue.
Typical Abundance
Grows into thick, dense clumps.
Protection
While the Bay Mussel does provide an abundant food source for many organisms, it is very common along coastal British Columbia and therefore is not critical habitat. However, it is still important habitat and areas lost are usually made up for by placement of additional rock in the intertidal.
Balanced Environmental Services Inc. does not authorize the reproduction of any images, documents or other information contained within. The environmental consulting information provided does not necessary reflect the views of those parties identified. Any copying in part or in whole of any of the information presented on this site is strictly prohibited without the written consent of Balanced Environmetnal Services Inc.
Employee Login