Kunio Shirakihara / Professor / Division of Environmental Studies
Department of Natural Environmental Sciences / / Fish population dynamics

Career Summary
1975: Graduated, Faculty of Agriculture, The University of Tokyo
1980: Doctor of Agriculture from The University of Tokyo
1981: Research Associate, Simonoseki University of Fisheries
1987: Associate Professor, Nagasaki University
1995: Professor, Mie University
2001: Professor, The University of Tokyo
Educational Activities
Graduate School: Marine Environmental Science, Fundamentals of Natural Environmental Studies, General Practice in Marine Environmental Studies, Seminar on Natural Environmental Studies, Seminar on Marine Environmental Studies
Research Activities
1. Adaptive management of living marine resources
Management of living marine resources operates in highly uncertain situations. Adaptive management, which focuses on decision-making based on monitoring, is therefore essential in the face of uncertainty. We propose a management procedure using marine protected areas (MPAs) that employs a feedback mechanism to change the size of an MPA depending on the observed population fluctuations (Ref. 1). This procedure can be employed to recover a depleted population and sustain the population at a predetermined target level.
2. Fish stock assessment
Estimation of abundance or biological parameters of fish stocks (populations) is an important component of managing living marine resources. We have proposed a method for estimating migration (movement) rates using a two tag-release/one recovery experiment (Ref. 2). We clarified the distribution and seasonal movement of clupeids in Lake Tanganyika (Ref. 3).
3. Ecology and conservation of coastal dolphins
The finless porpoise and Indo-Pacific bottlenose dolphin inhabiting coastal waters are exposed to a wide variety of human activities and their continued existence may be threatened.
Using aerial sighting surveys, we show that despite the occurrence of favorable topographical conditions in the sea, the density of finless porpoises is relatively low in the Inland Sea. Furthermore, we were able to implicate habitat fragmentation as being responsible for this current distribution (Ref. 4). We clarified that the Indo-Pacific bottlenose dolphin is a year-round resident of Amakusa in Western Kyushu, and that the population size is as low as 218 individuals (Ref. 5).
1) Kai, M. and Shirakihara, K.: A feedback management procedure based on controlling the size of marine protected areas. Fisheries Science, 71, 56-62 (2005).
2) Shirakihara, K. and Kitada, S.: Estimating migration rates from two tag-release/one recovery experiments. ICES Journal of Marine Science, 61, 821-828 (2004).
3) Phiri, H. and Shirakihara, K.: Distribution and seasonal movement of pelagic fishes in southern lake Tanganyika. Fisheries Research, 41, 63-71 (1999).
4) Shirakihara, K., Shirakihara, M. and Yamamoto, Y.: Distribution and abundance of finless porpoise in the Inland Sea of Japan. Marine Biology, 150, 1025-1032 (2007).
5) Shirakihara, M., Shirakihara, K., Tomonaga, J. and Takatsuki, M.: A resident population of Indo-Pacific bottlenose dolphins (Tursiops aduncus) in Amakusa, western Kyushu, Japan. Marine Mammal Science, 18, 30-41 (2002).

Other Activities
Editor of Fisheries Science
Executive Committee member of the Japanese Society of Fisheries Oceanography
Regional Councilor of the Japanese Society of Fisheries Science
Review Committee member for the administrative agencies incorporated into the Ministry of Agriculture, Forestry and Fisheries
Future Plan
I will continue to study fish population dynamics, focusing on the sustainable use of living marine resources, and conservation of biodiversity and marine ecosystems, as well as the interrelationships between the marine and terrestrial environments.
Messages to Students
It is impossible to observe the entire marine environment using only your eyes. The sea is wide, deep and dark in its deeper areas. However, if you illuminate an area in which you have interest, you will be able to observe that part directly. Studying the structure and function of the marine environment, which is a little-known area, is an exciting and challenging task.