Abstract
1. Since the last ten years, author collected data of observations (9 cases) and dead birds (10 cases) of Aquila chrysaetos, a Natural Monument species, in Niigata prefecture.
2. Apparently, the reports on dead birds of this species are much more frequent compared with other prefectures.
3. The living range of this species in this prefecture on the snowy Japan Sea side, is over lowlands rather than high mountains, as generally believed.
4. Its greater abundance in this prefecture is correlated with high population of its prey, the hare Lepus timidus, as can be judged from hunting statistics.
5. The cause of its death was either illegally shot, found dead, or death by electric wire, etc. and local people are interested to have it staffed.
6. Various measures necessay for protection of this declining species are proposed, based on the data of observation and dead birds.
