This book summarizes and analyzes the biology, ecology, exploitation and management of small cetaceans in Japan. It describes the various types of cetacean fisheries in Japan and their historical development, the life histories and ecologies of the main species involved, and the history and problems of conservation and management. The data show that in some cases the number of small cetaceans harvested exceed sustainable limits and have led to depletion of populations. The book provides a case study of what can go wrong when the needs of industry and conservation collide. The descriptions of life history and ecology are relevant to issues of conservation and management, not just for cetaceans, but for all fisheries around the world.
Dr. Toshio Kasuya graduated in 1961 from the Division of Fisheries, Faculty of Agriculture, University of Tokyo, and obtained his Doctorate in Agriculture from the University of Tokyo in 1972. Dr. Kasuya had a long career in many prestigious Japanese institutions related to fisheries and marine mammals conservation and management. From April 1961 to March 1966, he was a researcher at the Japanese Whales Research Institute. In April 1966 he joined the Ocean Research Institute at the University of Tokyo, where he was a Research Associate until March 1983. In April 1983 he joined the Far Seas Fisheries Research Laboratory of the Japanese Fisheries Agency where he exercised as Project Leader and later until March 1997 as Division Director. From April 1997 to March 2001, Dr. Kasuya has been a Professor at the Faculty of Bioresources, Mie University, and from April 2001 to March 2006 a Professor at the Division of Animal Sciences, Teikyo University of Science and Technology.
HISTORY OF JAPANESE CETACEAN FISHERIES
Outline of History of Small-Cetacean Fisheries
Importance of History
Iruka vs. Kujira Conservation Measures
Small Cetaceans and Related Fisheries
Recent Statistics for Small-Cetacean Fisheries
Hand-harpoon Fishery for Dolphins and Porpoises
Pre-historic Operations
Hand-harpoon Fishery for Small Cetaceans (1): before World War II
Hand-harpoon Fishery for Small Cetaceans (2): after World War II
Expansion of Dall's Porpoise Fishery toward the 1980s
Statistics of the Dall's Porpoise Hand-harpoon Fishery
Hand-harpoon Fishery off Choshi
Hand-harpoon Fishery around Taiji
Crossbow Fishery in Nago
Drive Fisheries for Dolphins
Coasts of Noto Peninsula, Sea of Japan
Tsushima Islands, Tsushima Strait
Iki Island, Tsushima Strait
Goto Islands, East China Sea
Northern Kyushu and Yamaguchi Prefecture
Sanriku Coasts, North Pacific
Izu Peninsula, North Pacific
Operation Types
Dolphin Species Taken by the Izu Fishery
Catch Statistics and Magnitude of Operation
Taiji, North Pacific
History of the Dolphin Fishery
Catch Statistics
Fishing Season
Trend in the Dockside Price
Nago, Okinawa Island
Miuranishi, Western Shikoku
Small-type Whaling
Origin
Operation Pattern
Management of Cetacean Fisheries in Japan
Fishery Acts
Rule for Regulation of Whaling
Rule for Regulation of Mother-ship Fisheries
Rule for Regulation of Steamship Whaling
Rule for Regulation of Small-type Whaling
Rule for Regulation of Specified Offshore Fisheries
Alterations of Whaling Regulations and International Relationship after World War II
Current Regulation of Cetacean Fisheries
Other Laws on Conservation of Cetaceans
Act on Protection of Fishery Resources
Act for Conservation of Endangered Species of Wild Fauna and Flora
Cultural Heritage Protection Act
Regulation of Fisheries for Dolphins and Porpoises
Historical Background and Early Government Actions
Actions of the Fisheries Agency
Measures Taken with Regard to Incidental Takes and Strandings
Problems in Management of Incidental Mortality
Catch Quotas for Dolphins and Porpoises
Moving Toward the End of Commercial Whaling
Small-type Whaling
Brief History
Actions related to the Moratorium on Commercial Whaling
Large-type Whaling
Before World War II
After World War II
Pelagic Whaling
Establishment, Expansion and Reduction
Background of Overfishing
Establishment of Nihon Kyodo Hogei
Restructuring of the Whales Research Institute
The Institute of Cetacean Research and Scientific Whaling
BIOLOGY
Finless Porpoise
Description of the Species
Scientific Name and Type Locality
Distribution
Worldwide Distribution
Taxonomy and Geographical Variation
Distribution of Finless Porpoises in Japan
Local Populations of Japanese Finless Porpoises
Abundance and Seasonality of Distribution
Seasonal Movements
Problems in Estimating Abundance
Abundance of Japanese Finless Porpoises
Abundance Decline in the Inland Sea Population
Background of the Abundance Decline
History of Protection of Finless Porpoises in Japan
Life History
Parturition Season
Growth
Reproductive Cycle
Social Structure
School
School Size
Dall's Porpoise
Description
Taxonomy
Population Structure
Pigmentation Pattern
Osteology and Body Length
Breeding Areas of Dalli-type Dall's Porpoises
Accumulation of Pollutants
Parasite Load
DNA and Isozymes
Population Structure: Summary and Future Studies
Life History
Age Determination
Segregation Viewed from Body Length Composition
Neonatal Body Length and Parturition Season
Mating Season and Gestation Period
Geographical Variation in Breeding Season
Reproductive Cycle
Female Sexual Maturity
Male Sexual Maturity
Longevity and Age Composition
Body Length and Growth Curve
Feeding Habits
Food Consumption
Prey
Social Structure
School Size
Behavior in Relation to Age and Sex Structure
Abundance and Trends
Populations around Japan (see also Chapter 2)
Offshore Populations
Striped Dolphin
Description
Sea Surface Temperature
Geographical Distribution
Population Structure in the Western North Pacific
Population and Management
Geographical Distribution and Population Structure
Osteology
Body size
Genetics
Mercury Level
Fetal Size and Migration Timing
Suggested Population Structure
Life History
Age Determination
Body length at Birth
Body Length Composition
Mean Growth Curve
Male Sexual Maturity
Female Sexual Maturity
Declining Age of Females at Sexual Maturity
Seasonality of Reproduction
Seasonality of Male Reproduction
Female Breeding Cycle and Annual Pregnancy Rate
Female Reproductive cycle and Age
Historical Change in Female Reproductive Cycle
Age Composition, Sex Ratio and Apparent Mortality Rate
School Structure
Food Habits
Effect of Fisheries on the Population
Bottlenose Dolphins
Taxonomy of the Genus Tursiops
Identification of Bottlenose Dolphins around Japan
Distribution of Bottlenose Dolphins around Japan
Life History
Age Determination
Gestation Period, Fetal Growth and Breeding Season
Sex Ratio
Age Composition
Body Length Frequency
Growth Curve
Male Sexual Maturity
Sexual Maturity and Reproductive Cycle of Females
Comparison between the Pacific and the Iki Samples
Life History Parameters
Background of the Change
Short-finned Pilot Whale
Description
Distinction between the Globicephala spp.
Description of Short-finned Pilot Whale
Distribution of Short-fined Pilot Whales
Northern and Southern Forms off Japan
Dawn of Japanese Cetology
Confusion and Reorganization
More about Japanese Pilot Whales
First Encounter with the Northern Form
Distinction between the Two Forms
Adaptive Significance of Body Size
Taxonomy of the Two Forms of Short-finned Pilot Whale
Life History
Viewing Life through Carcasses
Age Determination
Growth
Female Reproductive Activity
School Structure
Mixed School
School Size
Males in the School
Copulation Partner and Paternity
Genetic Relatedness among School Members
Summary of School Structure
Post-reproductive Females
Interaction with Human Activities
Catch History
Abundance and Trends
Problems in Management
Baird's Beaked Whale
Description
Distribution
Outline of the Distribution
Regional Distribution and Population Structure
Baird's Beaked Whales along the Pacific Coast of Japan
Food Habits
Stomach Contents
Diving and Feeding
Life History
Tooth structure and Age Determination
Sexual Maturity
Fetal Growth and Gestation Time
Body length and Age
Physical Maturity
Female Reproductive Cycle
Social Structure
Sexual Maturity and Tooth Eruption
School Structure
Sex Ratio
Why Do Males Live Longer?
Abundance
History of Exploitation
Type of Whaling Operation
Catch Statistics
Manipulated Statistics and Management
Pacific White-sided Dolphin
Description
Populations and Their Distribution
Growth and Sexual Dimorphism of the Dorsal Fin
Materials and Methods
Body Length Composition and Neonatal Length
Body Length and Age
Sexual Maturity
Sexual Dimorphism of the Dorsal Fin
Discussion
Closing Chapter : Cetacean Conservation and Biologists
The Community I Grew up in
Industry and Conservation
Cetacean Tragedies I have Witnessed
Striped Dolphins of the Pacific Coast of Japan
Sperm Whales in the Western North Pacific
To Avoid Future Tragedies
Unresolved Questions on Cetacean Biology
Factors that Determine Breeding Season
Function of Post-reproductive Females
Social Sex in Cetaceans
Greater Male Longevity in Baird's Beaked Whales
My View on Cetacean Conservation
Target to Conserve
Element to Conserve
Why Culture
Evidence of Cetacean Culture
Responsibility of Cetacean Scientists