Mussels

Mussels are a group of edible and non-edible bivalve mollusks in the family Mytilidae, known for their elongated, dark shells and a muscular foot that secretes byssal threads to anchor the animal to solid surfaces. The most familiar edible species belong to the genus Mytilus, including the blue mussel (Mytilus edulis) and the Mediterranean mussel (Mytilus galloprovincialis).

Biology and ecology: Mussels are filter feeders. They extract phytoplankton and other particulates from the water using their gills. They attach to rocks, pilings, or nets via byssal threads secreted by the foot. Mussels are dioecious and release eggs and sperm into the water for external fertilization; the larvae are free-swimming veligers before settling as juveniles. Lifespans vary by species but can span several years.

Habitat and distribution: Mussels are found in temperate and cold waters around the world, from the Atlantic and Pacific coasts to the Mediterranean. They favor rocky shores and protected subtidal zones where they form dense beds. Warmer-water mussels include the green-lipped mussel (Perna canaliculus) of New Zealand and the Asian green mussel (Perna viridis).

Human use and aquaculture: Many species are cultivated commercially through raft, longline, or bottom culture, and are valued for their meat as a seafood product. Wild harvests support local economies, but management of populations and water quality is important to sustain yields.

Safety and ecology: Mussels can accumulate toxins produced by harmful algal blooms, such as paralytic, amnesic, and diarrhetic shellfish poisons, so harvest is regulated by monitoring programs. They also contribute to water quality by filtering particulates, but overharvesting or habitat loss can harm reef systems and biodiversity. Individuals with shellfish allergies should avoid them.