Abstract
The sika deer (Cervus nippon centralis) population in Iwate Prefecture is the northernmost on Honshu Island, Japan. The management principle of Iwate Prefecture before the 1980s used to be the preservation of this population. Accordingly, the population had gradually increased, as did pest damage to agriculture and forestry. Thus, the prefecture changed its principle from preservation to control, and began several monitoring projects focused on the distribution of the deer, records of agricultural and forestry damage, population density, life history and ecological analyses focused on items such as foods, nutritional conditions, age structure etc., dwarf bamboo (Sasa nipponica) biomass and grazing by deer, and helicopter censuses. Population control greatly reduced the amount of damage, but new problems have also started to occur recently: the enlargement of the distribution of the deer and increased agricultural damage. In order to solve these problems, precise judgment of area characters, control of distribution enlargement, intensive control of damage by deer living close to villages, and improvements of monitoring methods are needed.
