HOPE Report No.32 2004-07-18
HOPE 2nd International Lecture
Date: July 3rd, 2004
Place: Freude, Inuyama
Title: The 2nd Imanishi-Itani Memorial Lecture: Conservation Biology and
Jyuichi YAMAGIWA (Kyoto University, Japan)
Long-running study of wild Gorillas: a systhesis of scientific research
Tamaki Maruhashi (Musashi University, Japan)
Long-running study of Yakushima monkeys: What we know and what we should
do in future.
Thomas Struhsaker (Duke University, USA)
Becoming a conservation biologist.
This is the second "Imanishi-Itani Memorial Lecture" that is
to the honor of the late Kinji Imanshi (1902-1992) and the late
Jun'ichirou Itani (1936-2001).
Imanishi and Itani and their colleagues
started the field survey of wild Japanese monkeys in 1948, that provided
the basis of the primatological studies in Japan. The first Imanishi-Itani
Memorial Lecture was given by Frans de Waal in 2002 when we celebrated the
centinal anniversary of the birth of Imanishi.
The second one 2004
highlighted the pioneering work by Dr. Thomas Struhsaker. He should be one
of the pioneers who made a parallel efforts both in the scientific
research and wildlife
conservation of nonhuman primates. Dr. Struhsaker talked about his
conservation efforts in Africa, especially Kibale Forest in Uganda.
talk was franked by the two related talks given by Dr. Yamagiwa working on
wild gorillas and Dr. Maruhashi on wild Yakushima monkeys.
Long-running study of Yakushima monkeys. What we know and what we should do in future.
Tamaki Maruhasi, Musashi University
In 1993, Yakushima Island was registered as the first World Natural Heritage in Japan. The island occupies the southern limit of the
distribution range of Japanese monkeys and its monkey population is classified as a subspecies, Macaca fuscata yakui. The first field study
was done in 1952 by Itani and Kawamura who reported that small troops were inhabiting continuously with severe territoriality. Since 1973 we
have started long-term study of wild monkey troops used by habituation and individual identification in their natural habitat, the lowland
subtropical forests near seashore.
The population density in our study site, the western slopes of Mt.
Kuniwari, was over 100 monkeys per square kilometer. During 30 years' study period, four troop extinction were observed and one incident of
mass mortality happened in 1999. It is thought that the population density has nearly come up to it's carrying capacity and that the
inter-troop competition for land, that is, food resources was a key factor for the frequent troop's extinction, fission and takeovers by
non-troop males. The research activities in this study site revealed a model of socio-ecological troop dynamics on Japanese monkeys. The
studies provided diverse comparative ecological and sociological data in evergreen forests in comparison with the deciduous forests.
To promote the long-term study on wild monkey population and conserve their habitat, three activities were essential;
(1) museum activity and education,
(2) conservation on the natural forest, and
(3) wild life management.
The confidence of island people to the researchers through these three activities was one of the most important drives for long
study and nature conservation. In a remote island, Yakushima, the area of World Natural Heritage was only one fifth of the whole Yakushima
after the wide range logging. Continuous cooperation between local people and researchers will make both the future possibilities and
present solutions be more and wiser.
Subspecies, Macaca fuscata yakui
Yaku field work course students listen the history of forest and people at Yakushima Island.