Due to the effects of the warm Tsushima current, the island has relatively mild weather year-round average annual temperatures of 12 °C; even snowfall of 10 cm is rare.

The island is covered with evergreen deciduous trees, including Eurya japonica.

It, with neighbouring, and much smaller, Oshakujima, have been recognised as an Important Bird Area (IBA) by BirdLife International for their colonies of black-tailed gulls.

In the Edo period, it was part of the holdings of the Sakai clan at Shonai Domain and an occasional port for the kitamaebune coastal trading vessels.

As of April 1950, the village of Tobishima and thus the island was annexed by the city of Sakata, Yamagata.