Developers have cut large tracts of forest for agricultural and urban expansion and to create commercially important cedar plantations. This habitat loss has forced monkey troops into increasingly isolated pockets of forest, such as those around Shiga Kogen. The concentration of macaques in shrinking habitat has created what some biologists call a civil war between monkeys and humans. The conflict occurs because the monkeys, seeking food, come out of the degraded forests to raid farm crops. A macaque troop can destroy a farmer's entire harvest, so farmers try to exterminate the animals.
Farmers trap thousands of monkeys yearly, and professional hunters account for many more.
Biologists who study the monkeys are increasingly concerned about the primate's future. The macaques plight is long standing. The U.S. federal government listed the species as threatened almost 20 years ago. The most northerly nonhuman primate in the world, the Japanese macaque occurs on three of the four main islands of Japan and on a few small outlying islands. Stocky and heavily furred, the species has earned its common name, snow monkey, by surviving in areas with harsh winters.