Japanese macaque
Sai occupies the western coastline of Shimokita Peninsula, facing the inlet to Mutsu Bay from the Tsugaru Strait. Much of the village is within the limits of the Shimokita Hantō Quasi-National Park. The mountainous area is home to many indigenous plant and animal species. Wildlife includes Japanese macaque monkeys, "kamoshika," "tanuki" and Asian black bears. Most of the population resides in coastal hamlets. Approximately 90% of the village area is forested; of which 90% is national forest.