The closeup of the map in the Japanese Imperial Navy Headquarters shows the fictional island of Taratupa at a longitude of 154 degrees 40 minutes and a latitude of -4 degrees. This places Taratupa just northeast of Green Island of Papua New Guinea and due north of Bougainville Island of the Solomons.
The title is from the nautical term "Scuttlebutt" which describes the type of rumor or gossip between sailors that occurs around the large water barrel on sailing ships or in later years, around the water cooler.