Tanaka's force departed the Shortlands just after midnight on November 30 for the run to Guadalcanal. Tanaka attempted to evade Allied aerial reconnaissance aircraft by first heading northeast through Bougainville Strait before turning southeast and then south to pass through Indispensable Strait. Paul Mason, an Australian coastwatcher stationed in southern Bougainville, reported by radio the departure of Tanaka's ships from Shortland, and this message was passed to Wright. At the same time, a Japanese search aircraft spotted an Allied convoy near Guadalcanal and communicated the sighting to Tanaka who told his destroyer commanders to expect action that night and that, "In such an event, utmost efforts will be made to destroy the enemy without regard for the unloading of supplies."