On 20 May 1776 the British forces under the command of Lieutenant Clayton formally took their leave of Port Egmont, leaving a plaque asserting Britain's continuing sovereignty over the islands. The Falkland Islands remained an important outpost for whalers and sealers who used the islands to shelter from the worst of the South Atlantic weather. By merit of their location, the Falkland Islands have often been the last refuge for ships damaged at sea. Most numerous among those using the islands were British and American sealers, where typically between 40 and 50 ships were engaged in hunting fur seals.