Yes. Fresh oysters properly refrigerated are wholesome and
nutritious throughout the year. They spoil rapidly at high
temperatures, however. The belief that oysters were unsafe to eat in
May through August arose in earlier days when refrigeration was less
prevalent than it is today.
It compresses the valves of its shell and forces water backward in jets
near the shellhinge. The force drives the scallop in the direction of
the shell opening. The bivalve appears to be clapping the two sides of
its shell together.