"The Admiralities became key to isolating Rabaul and the neutralization of New Britain. The seizure of Manus Island and Los Negros Island cut supplies from all points north and east. By 1944 Seabees had transformed those islands into the largest Lion and Oak in the Southwest Pacific. The Lion became the main supply and repair depot of the Seventh Fleet. The capture of Emirau completed the encirclement of Rabaul. A strategic two-field Oak, with depots, dry dock, and PT base was constructed there."