II. HABITAT AND DISTRIBUTION The ribbed mussel can be found
along the Atlantic coast from the Gulf of Maine to Florida and
the Gulf of Mexico (Franz 2001). It also reported from the San
Francisco Bay on the West coast where it was introduced.
Geukensia demissa occurs in the Indian River Lagoon. III. LIFE
HISTORY AND POPULATION BIOLOGY Age, Size, Lifespan: Adult
Geukensia demissa can live for more than 15 years and grow to
nearly 10 cm in length. The age of the ribbed mussel can be
determined by counting the annual growth ribs on the shell
(Brousseau 1982). Juvenile mussels can mature when they reach 12
mm. Geukensia demissa can be found among intertidal oyster reef
clusters in numbers over 1,500 per m2 (Coen et al. 1999). Unlike
oysters, ribbed mussels have the ability to reattach if
dislodged, providing this species with more opportunities to
respond to disturbance. Densities of 2000 up to 10,000 per m2
have been reported for this species in areas along the northern
Atlantic coast. Ribbed mussels have separa