DIWPA: DIVERSITAS in the Western Pacific and Asia

DIWPA News Letter
Office: Center for Ecological Research, Kyoto University, Otsu, Shiga, Japan

Shin-ichi
NakanoMessage from the chairperson
It has been a long time! In thecoming July, the 10th Congress of
the East Asian Federation of
Ecological Societies (EAFES) isgoing to be held in Jeju Island,South Korea. At this stage, thecongress is going to be held inperson. EAFES is the organization
where ecological societies ofChina, South Korea and Japan
collaboratively established afederation to promote ecologicalscience in East Asia. The three
Ecological Societies take turns
organizing the joint meeting(EAFES Congress) at least once in
2 years. In the last time, theEcological Society of China (ESC)
hosted the 9th Congress held in
Hohhot, the capital of Inner
Mongolia in the north of China, andit was very greatly successful.
According to the ESC’s website,
the 9th EAFES had 450 registeredparticipants from 9 countries(China, South Korea, Japan,Mongolia, France, Pakistan, Russia,
Sri Lanka and Thailand) attended
both onsite and online. The numberof abstracts was 249 (Chinese 150,foreign 99) with 136 oralpresentations (Chinese 84, foreign52) and 82 posters (Chinese 42,foreign 40) focusing on the 8sessions. The presentations in the
9th EAFES were dominated byyoung researchers such as postdocs and graduate students, and all
those talks were so excellent andimpressive. EAFES Congress
covers a wide range of topics inecology, and I believe that everyone
interested in ecology, biodiversity,conservation and environmental
sciences would enjoy joining there.
The important information of the10th EAFES will be released on thewebsite of the Ecological Societyof Korea (ESK). So, as the capacityof the EAFES Secretary Generalfor the Ecological Society of Japan,
I warmly welcome all of you to join
the 10th EAFES!
The website of ESC:
http://www.esc.org.cn/tdetail.html?
id=184&contentId=1941
The website of ESK:
http://www.ecosk.org/Jeju Island

1

March2023

No. 48Atsushi
IshidaMessage from the Secretary General
Now Japan is entering the 8th waveof the new corona virus (COVID-19).
Currently, there is concern about
the spread of the XBB.1.5 variant
i n J a p a n . H o w e v e r, s o c i a l
restrictions for COVID-19 have
gradually eased in Japan. In 2022,
we were able to hold the DIWPAInternational Field Biology Course(IFBC) for the first time in twoyears. However, only younginternational students andresearchers who were staying inJapan could participate in theDIWPA IFBC in 2022, because it
was not easy to obtain the VISA
from abroad. As the result, I am
pleasure to publish the report ont h a t D I W PA I F B C i n t h i s
newsletter. In 2023, we hope toopen the door to the DIWPA IFBCas much as possible. In the next
volume, we will be able to provide
more information on the DIWPAIFBC in this year. Together with theDIWPA newsletter, we hope tocontinue to enhance its function as
the platform for the exchange ofinformation among countries onbiodiversity conservation andrelated ecosystems and societies. To
this end, we look forward toreceiving your reports to theDIWPA newsletter.

DIWPA News Letter No.48

RertopResearch experience at Chichijima,Ogasawara Islands: Examining treehabitat relationships and revisiting
island biogeography theory
Christmas Uchiyama
Laboratory of Forest Resources, Graduate School of Agricultural Science,Kobe University (Japan)

Last November 16-23, I had a chance to visit Ogasawara
Islands through a field biology course/training provided
by the DIVERSITAS in the Western Pacific and Asia(DIWPA), Center for Ecological Research (CER).
Ogasawara is designated as a World Natural Heritage
Site in 2011, located 984 km from Tokyo. I joined aresearch survey on the growth of endemic dwarf trees inOgasawara with Prof. Atsushi Ishida (CER, Kyoto
University), Prof. Yuzou Sano (Hokkaido University),
Ms. Maruyama and Mr. Kanji (the last two are students
who are involved in the survey as part of their thesisstudy). Prof. Ishida is the lead investigator of theresearch and he has been conducting research projects
and awareness-raising activities for the locals inOgasawara. When I asked how many times he has beenin the island, he answered that he cannot count as he has
been going back and forth since more than 20 years ago.
The research project of Prof. Ishida is locatedChichijima, Ogasawara and involves monitoring growthof plant species (Fig. 1) examined at the drought dwarf
forests such as Shimamura (Juniperus taxifolia), Shima-isunoki (Distylium lepidotum), Himetsubaki (Schimamertensiana), Himefutomomo (Syzygiumcleyeraefolium), and Terihahamabou (Hibiscus glaber),among others.
The research survey aims to investigate on thegrowth of the endemic trees given the limited soil andwater availability on the island. I am grateful and lucky
to be able to be selected as a participant for theInternational Field Biology Course (IFBC) under thistheme, which is very much aligned with my researchinterest. Specifically, my participation to the IFBC has
provided me the opportunity to: (1) observe the growthof endemic dwarf forest species in Ogasawara; (2) gain
knowledge and field experience on climate-growth
response of trees in drought-prone ecosystems such as
those with poor soil quality/condition; (3) engage inknowledge-exchange with other young students/
researchers on topics such as forest/plant science,
biodiversity conservations in islands, control of invasive
species, etc.

Fig. 1. Left image shows the needle of Juniperus taxifolia while the right image shows the survey team doing maintenance on a dendrometer device installed in
one of the monitored trees.

2DIWPA News Letter No.48

Fig. 2. The team with the mascot of Ogasawara-maru before leaving Tokyo.

I have always dreamt of visiting Ogasawara
since I have been to Japan. This group of islands is agood model of island biogeography, where processes ofisland birth and growth and the high endemism it
provides can be observed. For me, being able to go toOgasawara is like a dream come true. Even though it
takes a 24-hour journey by Ogasawara-maru ferry (Fig.
2), I think that the journey is part of the reason why theisland is worth to see. In fact, during the sea travel, wewere able to have a chance to enjoy the unique species ofsea birds that are inhabiting the small islands of theOgasawara group of islands. It is my first time to see“Katsuodori” (Brown Booby or Sula leucogaster) so I
was very amazed observing their flying and feeding
behavior (Fig. 3). I read that November to December are
the breeding and nesting months for Brown Booby andthat they typically lay two eggs per breeding season.
They must have favored the availability of many
breeding sites in Izu islands and Ogasawara islands.
I love the biodiversity which islands such as
Ogasawara and the islands in my home country, thePhilippines, possess. It is very interesting how that levelof endemicity and biodiversity has been created,Fig. 4. Collecting data from dendrometers at tree
trunk.

meaning, some species of plants and animals are only
found in Ogasawara. I always feel amazed by the factthat island systems not only possess rich biodiversity, butthey are also characterized by rich culture and history.
Because of being remote geographically, similar withthat of the case of plants and animals, the culture inislands is generally different from the mainland. There
are also differences with regards to climate and thisultimately results to an increase in a species’ acclimation
potential to the existing conditions in the island. For
example, trees are sessile organisms and thus, they areunable to move or run away from adverse environmentaland climatic conditions. Some tree species persist andcontinue to grow and survive even if the habitat
conditions are not good. In the case of the dwarf species
in the forest of Ogasawara, the trees there have tobalance physiological functions and processes such as
photosynthesis and respiration with that of growth andsurvival. If there is enough source of water or soil
moisture needed for photosynthesis, they could
maximize growth or develop a growth strategy based on
physiological and morphological factors.

Fig. 5. Installation of the soil moisture sensor.

3Fig. 6. Micro-weather station at the study site, Mt.
Chuozan (the highest mountain in Chichijima,Ogasawara).

DIWPA News Letter No.48

universities/institutions, it is also expected that there will
be an opportunity to meet other students and researchers.
At the kitchen, while we are cooking, I was able to havesome talk/knowledge-exchange with fellow participants
and with other students of Kyoto University and I got toknow about their own research interests and topics. As
an example, Kanji Minagi taught me how to use thepressure chamber to determine leaf water potential (Fig.
8). Mio Maruyama, who is analyzing dendrometer dataof dwarf trees, have talked with me about her study as
both of our research topics are similar. Additionally, wepracticed tree-climbing together and she helped me
familiarized myself once again with the basic techniquesof tree-climbing.
Biogeography is the study of the patterns ofgeographic distribution of organisms and the factors that
determine those patterns. Being both a student and a
researcher, I am always fascinated with the concept ofendemicity and biogeography. Ogasawara Islands are achain of volcanic islands created about more than 40
million years ago formed along the oceanic subduction
zones. As these islands have never been connected to themainland, they have produced plants, animals and otherorganisms that are unique to the area. The theory ofisland biogeography predicts that species diversity on anisland is positively related to the size of the island, but
negatively related by the island's distance to themainland. There are a number of ways and possibility bywhich we can evaluate and re-confirm the theory of island
biogeography in Ogasawara through studying its
biodiversity and the ecological processes in the islands.
For instance, what I noticed is that the island vegetation isdominated by scrub communities such as Maruhachi(Cyathea mertensiana), Takonoki (Pandanusboninensis), and Ohama-gikyou (Lobelia boninensis). It
would also be interesting to analyze the relationship ofthese species with endemic faunal species such as
insects, mammals and birds which could be helping in
the dispersal of trees in the island (Fig. 9).

Research survey on ecophysiology of treesin Ogasawara
Changes in the stem growth of a tree can be measured
through a dendrometer device which records thediameter of the tree as well as daily and periodical
expansion and shrinkage of tree stem in high temporal
resolution. I observed and learned how dendrometers in
the field are monitored and how data are recorded using
a simple data collector (Fig. 4). On the hand, Figure 5
shows how a soil moisture sensor is being installed.
By analyzing the stem growth changes, we will
be able to determine the period of the day when the tree
experience water stress or drought. The growth
information can also be correlated with the climatic
variables such as precipitation and temperature. Figure 6
shows a photo of the microclimate monitoring
equipment available at the study site. These are essential
equipment for research topics that are related to climate
and tree relationships. More importantly, studying how
climate is affecting plants and trees are very relevant
these days due to the global climate change.
To be able to identify specific effect ofenvironmental and climatic changes on the trees,investigation of xylogenesis (the formation of water
conducting vascular tissue) can be conducted by way ofcollecting microcores from the stem of the trees. Figure
7 illustrates how microcore collection is done and thisparticular activity (morpho-anatomical analysis) is led
by Prof. Sano. I learned from Prof. Sano the basic
techniques of wood micro-core collection and sample
storage. He also provided me some advice and tips on
how to process the samples for subsequent analysis of
the cambium or the growing part of the tree trunk.
In my study in Miyazaki experimental forest, I
am investigating on the effect of increasing temperatureon the stem growth of Cryptomeria japonica. I also
conduct the same analysis as Prof. Sano as a third
component of my PhD research, and therefore, I am very
grateful to havereceived advice andtips from an expert
such as Prof. Sano.
Aside fromacquiring knowledge
from professors, I was
also able to acquire
knowledge from fellow
students. Our groupstayed in the Tokyo
Metropolitan University
Ogasawara Field
Research Station andsince the field station
has a joint use policy
Fig. 7. Prof. Sano collecting microcoreswith other groups/
from a tree at the study site.

Environmental education led by volunteer
groups and people’s organizations
In addition to working in the field, I also had a chance toobserve first-hand the conservation activities in
Ogasawara. For instance, we visited a facility led by
NPO Institute of Boninology called “Nekomachiaisho” (ねこ待合所), which literally means “waitingfor cats” (Fig. 10). This non-government organization
deals with the population of cats in the island especiallyin taking care of turned-over cats that were caught in theisland and in making them ready for adoption. Feral catsin Ogasawara pose threat to the population of endemic
species such as birds and other small endemic animals.
Thus, in order to conserve endemic species, it has been
an initiative from Tokyo Metropolitan Government to4

DIWPA News Letter No.48

Fig. 8. Practicing measurement of the leaf water potential using the pressurechamber.

promote trapping and transport of cats from the island toJapan’s mainland. Neko-machiaisho has been
instrumental in sending cats for adoption in Tokyo.
Aside from efforts regarding feral cat management,
there are other conservation efforts which promotes
citizen science. One group called NPO Ogasawara
Wildlife Research Society (NPO法人小笠原野生生物研究会)

Fig. 10. The cat-shaped facility called Neko-machiaisho.

seems to be very active in the island as well particularly
in terms of endemic plant species conservation andprotection. We had a chance to meet representatives ofthis group and I observed their passion and advocacy
towards the island’s endemic and endangered flora andfauna/wildlife and natural environment. They are
conducting volunteer activities such as controllinginvasive plant species, tree planting of endemic species,
beach cleanup and awareness-raising activity incooperation with various people from the academe,
government and the public and with the overall aim tocontribute to the conservation of the Ogasawara Islands(Fig. 11).

Unique culture and local practice inOgasawara
Matching the high biodiversity of the island is thepeople’s culture and way of life. People in Ogasawara
are very much appreciative of the nature and aware of
the changing conditions in the island. The history of theisland is complex, and the local people are modern-day
descendants of a multitude of racial and ethnic groups
based on the events of the past. However, one would
notice that similar with other island regions or nations,the people in Ogasawara has a way of life that is alignedwith their surrounding and thus, helps in the deepeningof the connection between nature and humans.
Ogasawara has a rich local culture and practices.
After staying there for a week for the IFBC, I feel likegoing back again to do some research activities there inthe future. I was very amazed not only by the uniquenatural environment of Ogasawara but also at how local
people express their gratitude to the visitors of theisland. When I boarded Ogasawara-maru for my journeyback to Tokyo on the last day of the IFBC, I wassurprised to have witnessed how local people honored
visitors by letting us experience the local tradition/practice. Passengers received good wishes for a safe
journey and a hope to be back in the island again. Thiswas done by way of giving an island symbol made from
Pandanus leaves and Hibiscus (Fig. 12). As Ogasawara-Fig. 9. Left image shows herb and scrub vegetation in the island. Right
image shows seeds of Pandanus boninensis indicating it has been eaten
by a mammal (likely an endemic rat).

5

DIWPA News Letter No.48

Acknowledging knowledge gained andexpressing gratitude
I thank Prof. Ishida and the whole DIWPA, Center forEcological Research, Kyoto University, for this great
opportunity to participate in a research activity in
Ogasawara and to experience its unique naturalenvironment (Fig. 14). I acquired various knowledge
from the IFBC and I feel more connected to nature after
joining the trip. I also thank the Tokyo Metropolitan
University (TMU) for providing such kind of researchfacility in the island. My gratitude goes to Prof. Sano aswell for sharing his knowledge on wood anatomy. I also
would like to thank my fellow students (Maruyama-sanand Minagi-san) for the knowledge-exchange andcooperation they have extended me. I wish to connect
with all participants and collaborate with them once
again in a future research endeavor.

Fig. 11. Our team’s photo with some members of the NPO Ogasawara
Wildlife Research Society.

maru ferry departs, we were shown send-off performancesfrom the local people and island tour operators (Fig. 13).
I was lucky because I surprisingly saw a group ofdolphins swimming nearby after the send-off and while
our ferry gets further away. I feel very humbled by thisexperience and it made me remember some tradition inand affinity with my home country, Philippines.

Fig. 12. Left: Our team together with all students who are doing research in Ogasawara and with the local people. Right: The island accessory with Hibiscus andPandanus as main components.

6DIWPA News Letter No.48

Fig. 13. Performances from the local people and tour operators.

Fig. 14. The scenic beauty of Chichijima from mountains to coast.

DIWPA OFFICE
Chairperson

Shin-ichi Nakano

Secretary General

Atsushi Ishida

Secretary

Hiroshi Kudo

Center for Ecological Research
Kyoto University509-3, 2-chome, Hirano, Otsu, Shiga 520-2113, JAPANTel : +81-77-549-8238
E-mail : diwpa@ecology.kyoto-u.ac.jp

Shoko Sakai

http://diwpa.ecology.kyoto-u.ac.jp/

Shigeo Yachi
Assistant Secretary Akiko Seki

7

DIWPA News Letter No.48