When young they are attached to the substrate by a byssus but mature animals are capable of swimming by the opening and rapid closing of the valves.

[6] Pecten maximus occurs in the eastern Atlantic along the European coast from northern Norway, south to the Iberian Peninsula, it has also been reported off West Africa, off the Macaronesian Islands.

[7] Once settled, sand, mud, gravel or living organisms coat the upper valve and the margin of the shell, with the tentacles and eyes, is all that is visible.

The swimming action is performed by rapidly clapping the valves and expelling jets of water from each side of the hinge so that it moves with the curved edge of the shell at the front.

Scallops which live in sheltered habitats grow faster than scallops in areas exposed to wave action, possibly due to the filter feeding apparatus being unable to function because of high concentrations of particulate matter in the water in areas subject to high levels of wave exposure.

Another factor that may be significant is that the processes of larval settlement and byssal attachment are rather delicate and would be disturbed in strong currents.

[7] Since the larval stage of Pecten maximus is relatively long, up to a month, the potential for dispersal is quite high, even smaller adults can use the byssus to drift too.

[7] In waters around the United Kingdom Pecten maximus become sexually mature at around 2–3 years old and when they reach 80 to 90 mm in shell length.

[11] Recent (as of 2021[update]) improvements in read length helped Kenny to resolve questions of copy number variation in P. maximus which were previously indecipherable.

[10] As well as the starfish species Asterias rubens and Astropecten irregularis, major predators of Pecten maximus are crabs such as Cancer pagurus, Carcinus maenas, Liocarcinus depurator and Necora puber, which will prey on the scallops as they grow.

[13] The larvae of Pecten maximus are attacked by the bacterium Vibrio pectenicida, which was described in 1998 as a new species after incidents of mortality among cultured scallops in France in the early 1990s.

[20] Pilgrims travelling to the town of Santiago de Compostella in Galicia took the shells of scallop with them, in honor of Saint James.

[20] Michel Callon, a sociologist, used a case study of scallop fishing in St Brieuc Bay in France to illustrate how the sociology of translation can be applied to understand the dynamics of science and technology.