Blue mussel

Blue mussel
Image: Derwent Estuary Program
Community type

Intertidal reef organisms

Habitat type

Rocky reefs, kelp beds and inter-tidal zone

Blue mussels are extremely common in the mid and lower Derwent estuary where they live in the intertidal zone. They attach to rocks and other hard substrates such as piers and jetties by strong thread-like structures called byssal threads. These threads are secreted by glands located in the foot of the mussel. Through the port of Hobart and in natural settings they can occur as a dense monoculture, with individuals heaping on top of each other. While mussels and the introduced Pacific oyster are the most visible mollusc, over 250 species were recorded from Taroona Beach in the lower Derwent estuary by the Tasmanian Marine Naturalists Society. Predation of blue mussels is greatest during the three weeks it spends as a planktonic larva. During this stage it is susceptible to predation by jellyfish and many fish species. Despite the hard shells of adults, blue mussels are preyed upon by moderate to large seastars, as well as pied oystercatchers, Pacific gulls, and water rats.

Much of the text within the species area of our website was written by Veronica Thorpe, as part of the Derwent River Wildlife Guide (2000).

The DEP has developed a variety of classroom and outdoor activities focused around the key estuary habitats of tidal wetlands, salt marshes and rocky reefs. These include classroom materials, online resources, interpretive walks, games and sensory experiences.