It slowly settles to the sea floor, extending the foot and withdrawing the velum. If the bottom is not suitable, the larva swims off again. When the pediveliger finds a suitable place to settle, such as rough or filamentous surfaces, it will secrete byssus threads and anchor itself in place. This setting habit can be exploited by growers wishing to capture wild scallop larvae. Once set, the juvenile scallops remain attached by the byssus threads for several months, before adopting a free living, bottom dwelling lifestyle.
Scallops can swim quite actively in a random fashion if disturbed.
This helps them avoid predators or escape unsuitable conditions. Scallops are well adapted to conditions in Atlantic Canada. They feed actively between 5 and 15 C, with optimum growth occurring around 10 C. Temperatures more than 21 C can be lethal. However, scallops can withstand winter temperatures in the Gulf of St. Lawrence, which may be below -1 C for several months. Growth rate varies with location, and is dependent upon temperature and food supply.