Underneath the pontoon at Rudders Boatyard the Deputy First Minister saw the oyster cages - where oysters are kept as broodstock to release larvae into the Haven to boost the existing population.
O dan y pontŵn ar Iard Gychod Rudders fe welodd y Dirprwy Brif Weinidog y cewyll wystrys - lle cedwir wystrys fel stoc mag i ryddhau larfa i'r aber i hybu'r boblogaeth bresennol.