SSISSN1341−2418
1341−2418
ISSN

OUTH PACIFICPACIFIC NEWSLETTERNEWSLETTER
OUTH

KAGOSHIMA UNIVERSITYRESEARCH
CENTERKAGOSHIMA
UNIVERSITYFOR THEINTERNATIONAL CENTER
FOR PACIFICISLAND ISLANDSSTUDIES
1-21-24, Korimoto, Kagoshima, 890-8580 JAPAN ●T E L: +81-99-285-7394
FAX: +81-99-285-6197

⿅児島⼤学国際島嶼教育研究センター
郵便番号 890-8580
⿅児島市郡元１丁⽬21番24号
電 話 099-285-7394
ファクシミリ 099-285-6197

E-mail: shimaken@cpi.kagoshima-u.ac.jp
Website:http://cpi.kagoshima-u.ac.jp/index.html

March
No.33
March 2200 21 25 No.26

KAGOSHIMA UNIVERSITYKAGOSHIMA
INTERNATIONALCENTERUNIVERSITYFOR ISLAND STUDIESRESEARCH
CENTERFORFOR
THETHE
PACIFICISLANDS(formerly
RESEARCH
CENTER
PACIFICISLANDS)

CONTENTS
Page
Introducing My Resarch
OTSUKA, Y.: Prevention of dengue fever in small islands of Micronesia···························1

Research Seminars ······························································································4Recent Publications ····························································································10

Cover photo: So-called the “Napoleon” Rock, Koshiki Islands, Kagoshima, Japan, September 2017(by Hiroto TAKAMIYA)INTRODUCING MY RESEARCH

Prevention of dengue fever in small islands of Micronesia
OTSUKA, Yasushi
International Center for Islands Studies, Kagoshima University
Medical care is a serious problem for islands. Medical facilities are never enough on remoteand small islands even in Japan. The same is true on Piis-Paneu and Pingelap Islands of theFederated States of Micronesia, where our center has conducted interdisciplinary researches (Fig.
1). These islands can be walked around in about an hour and have a population of about 200
people, and have no doctors and no nurses. I thought about what would happen if infectious
diseases were prevented, especially mosquito-borne infectious diseases, on such small islands.

Fig. 1. Maps of Piis-Paneu and Pingelap Islands of the Federated States of Micronesia.
Malaria is one of the most important mosquito-borne infectious diseases in the world. In
2000, 300 million people worldwide were infected with malaria and 1.2 million died. In recent
years, various control programs have been taken and the number of deaths is about 400,000 per
1

1

year. The protozoa, the pathogens of malaria, is transmitted by mosquitoes. However, not all
mosquito species transmit malaria protozoa. The malaria protozoa are transmitted by Anopheles
mosquito. Fortunately, there is no Anopheles mosquito in Micronesia, so there is no malaria
epidemic.
Lymphatic filariasis, which causes elephantiasis, is also a mosquito-borne infectious disease.
This lymphatic filariasis was once widespread in the tropics of the world, including Micronesia,
but is almost disappearing in the Federated States of Micronesia with ongoing global eradication
programs. The Republic of the Marshall Islands was declared in 2017 to be completely depletedof lymphatic filariasis. In Micronesia, Culex quinquefasciatus transmits lymphatic filariasis.
Culex quinquefasciatus has been also found on Piis-Paneu and Pingelap Islands, but people onthese islands are no longer infected with Lymphatic filariasis.
Dengue fever is also mosquito-borne infectious disease that is currently of concern inMicronesia. The first dengue outbreak to be found in the Federated States of Micronesia occurredin Yap in 1995. After that, a larger epidemic occurred in Yap in 2004, and an epidemic occurredin Kosrae in 2012. Dengue fever is an acute febrile illness that develops when infected withdengue virus belonging to the Flaviviridae family. After an incubation period of 2 to 7 days after
infection, symptoms such as fever, headache, and arthralgia appear, after which a rash appears
from the chest and trunk and spreads to the limbs and face. In addition, when dengue
hemorrhagic fever occurs, the circulating blood volume decreases due to plasma exposure fromblood vessels, which progresses to shock symptoms and blood coagulation in peripheral bloodvessels, resulting in massive bleeding from the digestive tract and death. Dengue fever has spreadin recent years, there have been 3.5 million infected people, 200,000 dengue hemorrhagic fever,and 20,000 deaths every year in the world.
There is no treatment specific for dengue fever. In addition, no vaccine has beencommercialized. In other words, the best way to control dengue fever is to prevent the spread ofmosquitoes that transmit the virus. Especially in remote islands with inadequate medical
resources, it is very important to prevent the spread of vector mosquitoes. Not all mosquito
species transmit dengue virus, only specific Aedes species do. The vector species of dengue virus
are Aedes hensilli and Ae. aegypti in Piis-Paneu and Pingelap islands, respectively. We need tofind out where these mosquitoes live and then come up with ways to control the outbreaks ofdengue fever. As result of our survey conducted on the two islands, we found that the mostcommon source of habitats of the mosquito larvae was plastic containers. This was followed bycoconut shells, concrete water tanks, drums and metal containers (Fig. 2). Most of them aregarbage in daily life. So, to reduce the mosquitoes that transmit dengue virus, people of theislands need to reduce garbage in daily life. The best way would be to collect the garbage anddispose of the garbage, but the small islands do not have the budget for that, nor is it likely to beable to build a garbage disposal facility on the island. Because that the distance of the dengue
vectors is only about 100 meters, even without incineration or landfill, it would be possible to22

prevent bloodsucking by building a garbage dumping site some distance away from where people
live.
Therefore, we made pamphlets explaining the importance of dengue virus control and thatgarbage from daily life is a source of mosquitoes that transmit dengue virus, andFig. 2. Various containers for mosquito larvae, A, B: Plastic container, C: Tin, D: Glass bottle, E;
Tire, F: Well, G: Coconut shell, H, Banana leaf, I: Tree hole.
distributed them to the islanders. I don't know if it is because of the pamphlet distribution andbriefing sessions or because mosquitoes come up as a topic of conversation every year when we
conduct our surveys, but the number of mosquitoes seems to be decreasing at some sites.
However, it is difficult to get all people of the islands to understand the importance of dengue
fever control, and since the situation has not changed dramatically, a long-term educational
campaign will be necessary.
In 2014, an outbreak of dengue fever occurred mainly in Yoyogi Park in Tokyo, and about
260 cases of dengue fever infection occurred in Japan. Imported cases of infection overseas anddiagnosed with dengue fever in Japan are reported every year, but the number of cases of dengue
fever transmitted in Japan was the first in 70 years. In this case, it is not certain how the dengue
virus invaded Japan, but the most probable route of invasion is for an affected person infectedwith dengue fever to enter Japan, be bitten by Ae. Albopictus, the vector mosquito species inJapan. The mosquito spread dengue virus by sucking blood from another person. In Japan, airport
thermography is used to screen people who have a high fever when entering the country.
33However, due to the incubation period of dengue fever, it may develop after entry. In addition,
there are cases of subclinical infection, which is infected with dengue virus but shows few
symptoms. When a person infected with such dengue fever enters Japan, that person may become
the source of infection and an epidemic may occur. Up to now, about 200 cases of imported
dengue fever have been reported every year in Japan. In other words, the dengue virus enters
Japan every year. In Japan, where Ae. albopictus is widely distributed, there is always thepossibility of an epidemic of dengue fever.

Research Seminars
No.209, 19 April 2021
“Changes in Amami People’s View of Nature: Through Conversations with Residents of
Sumiyo Town”
Dajeong SONG (International Center for Island Studies, Kagoshima University)[ABSTRACT]The Amami Islands are aiming to be registered as a World Natural Heritage Site in thesummer of 2021. The nature of the islands, which is evaluated as a World Natural Heritage Site,is an ordinary landscape for residents. It was also a resource used in daily life. Since the end of
the 1980s, nature observation groups have been established by residents in Amami-Oshima Island
and a nature conservation movement has occurred out of concerns for environmental degradation
caused by development. Meanwhile, tours to experience the forest, which had never existed
before, began at the same time. For example, hiking in the Kinsakubaru national forest, mangrove
kayaking, and a night tour to observe the endangered Amami rabbit. These tours have been
considered as ecotourism in the promotion of World Natural Heritage. In this presentation, I will
examine how nature has been viewed by residents in Sumiyo town where there is the Amami
rabbit’s habitat. Then, I will discuss how the Amami people should be involved in their nature.

No.210, 17 May 2021
“Basic Studies about Sea Pens Living from Kyushu to the Ryukyu Islands”
Yuka KUSHIDA (International Center for Island Studies, Kagoshima University)[ABSTRACT]
Sea pens are marine colonial benthic animals belonging to subclass Octocorallia (Cnidaria:
Anthozoa). They are specialized to live in sandy or muddy bottoms from shallow to deep water,and have roles as ecosystem engineers by providing habitat and shelter to associated marineorganisms such as small crustaceans, mollusks and fish. Recently, due to their ecological44

importance, sea pens have been treated as one of target taxa for protection and conservation in
Europe and Canada. However, basic studies on sea pens such as their taxonomy, diversity,
phylogeny, evolution and ecology are not very well studied as they are difficult to sample andanalyze specimens, and also due to low human interest towards marine organisms in sandy or
muddy environments. I have focused on basic research on sea pens in the northwestern Pacificduring my Ph.D. studies. As an example of this research, molecular phylogenetic studies
suggested that the species numbers of sea pens in the Ryukyu Islands are more than twice what iscurrently known in this region, and this result demonstrates the need to conduct further diversity
studies in sandy and muddy bottom ecosystems. Here, I would like to introduce sea pens andtheir research, spanning from Kyushu to the Ryukyu Islands.

No.211, 28 June 2021
“Life of Polychaetes in the Ryukyu Islands”
Masanori SATO (Emeritus Professor of Kagoshima University)[ABSTRACT]Polychaetes (Annelida) are major components of benthic communities in marine andbrackish waters, with about 1000 species known from Japan (about 200 species around theAmami Islands). Here are some interesting habits of the following species that live in the Ryukyu
Islands.
1) Nereidids inhabiting estuaries. Tylorrhynchus osawai Izuka, 1903 is distributed
throughout Japan to the south to the Ryukyu Islands (Amami-Oshima and Okinawajima islands),
showing a unique reproductive swarming just after times of high tide during a few nights closely
following the new and full moons mainly from October to December; epitokes derived from theanterior portions of the worms, which are filled with eggs or sperm, swim up into water column,
with the posterior portions of the worms degenerated and usually detached; they are transported
toward the sea on ebbing tides for spawning. On the other hand, the other several species
including Composeteia kumensis Sato, 2020, which is endemic to the Ryukyu Islands, seem tospawn without swarming (details unknown).
2) Spirobranchus corniculatus-complex (Serpulidae) usually associated with living massiveor plate-like poritid corals. The calcareous tubes of this species are buried in the skeleton of thecoral, with the multicolored (red, yellow, blue and so on) branchial crown spread outward forfeeding. Our fixed-point observation on Amami-Oshima Island indicates that the hermit
crab Paguritta vittata Komai & Nishi, 1996, which usually inhabit the empty tube of S.
corniculatus-complex, assists the successful settlement of the recruiting young of this species on
the living coral surface (Kikuchi et al., unpublished data).

55

No.212, 12 July 2021
“History of the Amami and Okinawa Islands Youth Groups in Occupied Japan”
Itaru NOUNAKA (Faculty of Law, Economics and Humanities, Kagoshima University)[ABSTRACT]How did the young people of the Amami and Okinawa Islands live during the occupation
period? This can be clarified by focusing on and investigating the Seinendan (Youth group) in
Amami and Okinawa during that time. The Seinendan is an organization. Therefore, theSeinendan can solve community problems that cannot be settled by individuals. Examining theactivities of the Seinendan is also the task of understanding the reality and wishes of young
individuals and groups of young people under American occupation.
The purpose of this presentation is to examine the history of the Amami and Okinawa
Islands Seinendans during the occupation period and to consider the actual situation of Amami
and Okinawa under the occupation system. In this study, I will focus on the bulletins such as“Okinawa Seinen” (Okinawa) and “Shinseinen” (Amami) published by the Seinendans. Througha comparative study of these collections, I would like to show the unique steps of the Amami andOkinawa Islands Seinendan organizations during the occupation era.
It is well-known that the Seinendans of mainland Japan were rebuilt after the World War Ⅱ,
and although there are regional differences, they have dealt with community issues and been
engaged in cultural movements. However, in the case of the Amami and Okinawa Islands, there
are unique developments that are different from those of the mainland, and it is necessary to
clarify their own history. The precondition for community issues in the Amami and Okinawa
Islands was the fact that they were directly controlled by the United States and separated from themainland. This was significantly different from the view of community issues for the youth
groups in mainland Japan.

No.213, 4 October 2021
“Construction of Research and Education Platform through the Coral Reef in Uplifted
Coral Reef Island Kikai-Jima Island, Japan”
Taro KOMAGOE (KIKAI Institute for Coral Reef Sciences)[ABSTRACT]The Kikai-Jima Island located in central Ryukyus, southwestern Japan has well-developed
coral reef terraces since the past 100 thousand years ago, because of sea-level changes and thehigh uplift rate. Geologically, it is one of the areas where local life and coral reefs’ benefits areclosely related. Based in Kikai-Jima, KIKAI Institute for Coral Reef Sciences (KICRS) has
started its activities in 2014. With the support of many researchers and local people, we aim toplay a role as a platform that connects coral reefs and society.
66The field of coral reefs attracts a diverse range of people, regardless of science or humanities,
from many academic fields to the fields of art. Taking advantage of this coral reef field, KICRS
conducts a research project “MIRAI Project” that integrates research in multiple fields centeredon coral reef science and considers the past, present, and future of the region. Also, we aredeveloping a research and education program “KIKAI College” for elementary school students touniversity students and adults.
The presenter has been researching to estimate the past marine environment using
sclerochronology methods, which is the study of physical and chemical variations (oxygen andcarbon stable isotope ratio, trace element concentration, and growth pattern) in the accretionary
hard tissues of the bivalve shells and the coral skeleton.
Currently, as a field-stay researcher, in addition to the geochemical analysis so far, I haveresearching coral reefs and ocean observations in collaboration with areas that can only be done
locally.
In this study group, I will introduce the research activities and the outreach activities on
Kikai-Jima.

No.214, 8 November 2021
“Onshore and Offshore Seismic Observations in the Northern Part of the Nansei-Shoto
Islands”
Yukihiro NAKATANI (Nansei-Toko Observatory for Earthquakes and Volcanoes, Research and
Education Center for Natural Hazards, Kagoshima University)[ABSTRACT]The region from the southern part of Kyushu to the northern part of the Nansei-Shoto
Islands is under complex tectonic conditions. The Philippine Sea plate has been subducting
beneath the Eurasian plate at the Ryukyu Trench, while the Okinawa Trough has been forming by
back-arc spreading. In order to elucidate seismic and/or volcanic phenomena caused by suchtectonics, observational studies are indispensable.
Many onshore seismic stations have been deployed in Japan since the 1995 Great
Hanshin-Awaji Earthquake, and a high-density observation network consisting of more than
2,000 stations is currently in operation. In the northern part of the Nansei-Shoto Islands, however,
the accuracy of hypocenter determination is low because seismic stations are located only at theislands that are linearly arranged along the arc. Therefore, Nansei-Toko Observatory for
Earthquakes and Volcanoes, Kagoshima University have been carrying out ocean bottom seismic
observation east off the Tokara Islands since 2014, even as have been enhancing the observationon the inhabited and uninhabited islands in order to understand precise seismicity.
In this presentation, I will introduce the onshore and offshore seismic observations in thenorthern part of the Nansei-Shoto Islands and the results obtained from them. I will also show an
77

overview of the earthquake swarm activity that occurred near the Tokara Islands (between
Akusekijima and Kodakarajima) in April 2021.

No.215, 13 December 2021
“Supporting Children’s Physical and Mental Health”
Marie AMITANI (Graduate School of Medical and Dental Sciences, Kagoshima University)[ABSTRACT]Even before the COVID-19 pandemic, the number of children with school refusal has been
increasing every year. According to a survey conducted by the Ministry of Education, Culture,
Sports, Science and Technology (MEXT) in 2021, one out of every 49 children was not attending
school. The reasons for this are not only relationships with friends and teachers, but also physicaldiscomfort, disruption of the rhythm of life, and problems with the Internet and games. In
addition, about 20% of the children feel a vague sense of anxiety without knowing the reason.
Against this backdrop, children’s behavior of school refusal is not only a matter of theirenvironment, such as friendships and relationships with teachers, but also requires comprehensive
support from physical, psychological, and social perspectives. Together with the children, parents,and school staff, it is necessary to assess the vicious circle that the children are in from a medical
standpoint, and to intervene and support them appropriately with regard to their physical ailments
such as abdominal pain and headache, as well as their psychosocial background, throughpsychotherapy, adjustment of the parent-child relationship, cooperation with schools, andunderstanding the problems in the local community. We are expected to intervene and support
them appropriately. For children who cannot attend school for some reason, we have beenworking to promote their social adjustment and independence by providing lifestyle guidance,intervention using Kampo medicine and yoga, psychotherapy, and support for cooperation
between parents and schools.
In this session, I will introduce the comprehensive support for children who cannot go toschool in order to improve their physical and mental health.

No.216, 24 January 2022
“Shell Utilization and Larval Release by Land Hermit Crabs in Iriomotejima Island”
Wataru DOI (Faculty of Fisheries, Kagoshima University)[ABSTRACT]As with aquatic hermit crabs such as Paguroidea, Coenobita crabs (Family: Coenobitae)
carry gastropod shells as a mobile home. The shells protect the spirally curved and less calcified
abdomen of the crab from mechanical damage and desiccation. They are adversely affected by ashortage of shells. Therefore, the availability of the shell resources can determine the abundance
88and size structure of Coenobita crabs in terrestrial environments. Because of their terrestrial life,
availability of shell resources is strongly influenced by human activities. I review the relationshipbetween the crabs and the humans by introducing the ecological studies of C. brevinamus in twoabandoned villages on Iriomotejima Island. Similarly to most semi terrestrial crustaceans withpelagic larval stages, the land hermit crabs expand their geographical distributions through theirinitial stage of life history. Coenobitid crabs have been found to release their larvae on various
types of substrates and with varying degrees of exposure to the open sea (e.g., sandy beaches,
rocky shores, coastal cliffs in inlets, semi-closed bays, and areas exposed to the sea). Coenobita
violascens in the Urauchi River showed discriminating reproductive behavior. Tree climbing took
two consecutive days when larvae were released on tree roots and swept into the river water.
Adaptive significance of tree-climbing behavior associated with reproduction will be discussed in
the latter half.

A view from one of the research seminars

99

Recent Publications+++ Journal +++South Pacific Studies Vol.42, No1/2, 2021-2022
Research Papers
SONG, D. and SUZUKI M.: Current Status and Problems of Nighttime Traffic Control aroundthe Santaro Road in Amami-Oshima
YAMAMOTO S., DJARWANINGSIH T. and WIRIADINATA H.: Use of Capsicum Peppers in
the Karimunjawa Islands, Central Java, Indonesia
RIWASINO J., YARAPEA A. and HENSON M.: Communication Process for Partnership Tree Farmingin Markham Valley of Papua New Guinea
TAKAMIYA, H.: Nissology, Island Archaeology, and the Archaeology of Ryukyus (1)+++ Kagoshima University Toushoken Booklet +++No. 14 KUWAHARA S.: Anthropology of the Amami Islands (March 2021)
No. 15 YAMAMOTO, S. and H. TAKAMIYA (eds.) : The Amami Aarchipelago, Rich in Nature andCulture Resources: History and Culture (March 2021)
No. 16 YAMAMOTO, S. and H. TAKAMIYA (eds.) : The Amami Aarchipelago, Rich in Nature andCulture Resources: Agriculture and Fishery (March 2021)

KagoshimaUniversity Toushoken Booklets No. 14, No.15, and No.16
10

10

SS

ISSN1341−2418
1341−2418
ISSN

OUTH PACIFICPACIFIC NEWSLETTERNEWSLETTER
OUTH

KAGOSHIMA UNIVERSITYRESEARCH
CENTERKAGOSHIMA
UNIVERSITYFOR THEINTERNATIONAL CENTER
FOR PACIFICISLAND ISLANDSSTUDIES
1-21-24, Korimoto, Kagoshima, 890-8580 JAPAN ●T E L: +81-99-285-7394
FAX: +81-99-285-6197

⿅児島⼤学国際島嶼教育研究センター
郵便番号 890-8580
⿅児島市郡元１丁⽬21番24号
電 話 099-285-7394
ファクシミリ 099-285-6197

E-mail: shimaken@cpi.kagoshima-u.ac.jp
Website:http://cpi.kagoshima-u.ac.jp/index.html

March
No.33
March 2200 21 25 No.26

KAGOSHIMA UNIVERSITYKAGOSHIMA
INTERNATIONALCENTERUNIVERSITYFOR ISLAND STUDIESRESEARCH
CENTERFORFOR
THETHE
PACIFICISLANDS(formerly
RESEARCH
CENTER
PACIFICISLANDS)