He operated in the Shima Province area (now part of Mie Prefecture), and later commanded naval forces for both Takeda Shingen and Tokugawa Ieyasu before his death in 1597 at the age of 57.

Ohama controlled the Kitabatake family's pirates and owned an atakebune, but was defeated by Kuki Yoshitaka, who had allied with Oda Nobunaga in his bid to unify Shima Province.

In 1582, after the collapse of the Takeda clan, Kagetaka then served as an admiral for Tokugawa Ieyasu and was awarded a fief of 1,500 koku in Suruga Province.

Thereafter, together with Mukai Masatsuna and Mamiya Takanori, he served under the command of Honda Shigetsugu in sea and land operations.

He was stationed in the village of Misaki in the Miura District, Kanagawa of Sagami Province at the entrance to Edo Bay.