Rockhopper penguin positions and islands became surrounded by subtropical water masses, resulting in a split between Northern and Southern rockhopper penguins. Many advance and retreat cycles of Patagonian icecaps during the late Pleistocene may have created a barrier to gene flow between Southern Pacific and Southern Atlantic populations, causing a split between Southern and Eastern rockhopper populations. Adult Rockhopper penguins have no land-based predators. They are eaten when at sea by leopard seals, fur seals, killer whales and blue sharks. Chicks and eggs are eaten by many birds including giant petrels, skuas, sheathbills and various types of gulls. Although the rockhopper penguin
Rockhopper Exploration viable rates. In July 2012, Rockhopper announced that it had entered into a conditional farm out agreement with Premier Oil plc whereby Premier will acquire 60% of Rockhopper's interests in its North Falkland Basin licences in exchange for an upfront cash payment of $231m, a contribution of $722m to Rockhopper's share of the Sea Lion development costs and a net exploration carry of $48m. Rockhopper will be fully funded on its share of the Sea Lion development through the contribution to costs and standby financing provided by Premier. First oil from Sea Lion is expected in 2020. Rockhopper holds interests