45th Scientific Symposium of the UJNR
Aquaculture Panel
Potential of aquaculture to mitigate impacts ofenvironmental changeInternational Conference Center Hiroshima
1-5 Nakajima-cho, Naka-ku, Hiroshima-shi, Hiroshima,730-0811, Japan
October 16th and 17th, 2017

Photo credit: Hiroshima Bay from the top of the mount by FEIS, FRA

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Aim of the Symposium
Environmental change impacts fisheries and aquaculture in many ways. Nutrient pollution isdriving eutrophication and dead zones; ocean acidification is changing water chemistry, andclimate change is already influencing our food supply, fresh water availability, weather andway of life. Aquaculture will be impacted by, and can also impact, these environmental changes
over various time and spatial scales. Aquaculture of finfish, shellfish and seaweed havedifferent threats, benefits and opportunities related to environmental change. Understanding
the global and regional trend of climate change, effects of environmental change on ecosystem
and aquaculture, technical improvement of aquaculture, and aquaculture industrial adaptation
to climate change are all research priorities of the National Ocean and Atmospheric
Administration (NOAA), the United States Department of Agriculture (USDA) and the Japan
Fisheries Research and Education Agency (FRA). The primary focus of this symposium will
be on the potential of aquaculture to mitigate impacts of environmental change, such as
sequestering carbon, bio-extraction of nutrients and CO2, and ocean acidification. We hope to
exchange ideas and discussion which will be beneficial in exploring science and technologythat will enable aquaculture to sustain in a changing environment and be used to mitigate theanthropogenic impacts on environment. We also hope the exchanged ideas will be developed
into our collaborative research efforts to resolve key issues and assist strengthening of
aquaculture industry in the United States and Japan.
ProgramMonday, October 16, 2017
Registration

13:00-13:30

Opening Session and Keynote Presentation
Welcome Remarks
Fuminari Ito, Japan Panel Chair, Executive Director,
Headquarters, FRA

13:30-13:40

Aim of the Symposium
Takuro Shibuno, Director,
National Research Institute of Aquaculture, FRA

13:40-13:50

Keynote Presentation and Introduction of NOAA grants(Moderators: Paul Olin and Junya Higano)New direction of management policies in the Seto Inland Sea, Japan in the changing
environment
Osamu Matsuda, Professor Emeritus, Hiroshima University
13:50-14:30
Break

14:30-14:50

Marine aquaculture’s role in providing nutritional security in a changing environment
Mike Rust, US Panel Chair, NOAA Fisheries Office of Aquaculture
14:50-15:30
An overview of NOAA grants on aquaculture and the environment
Shiyu Rachel Wang, Knauss Fellow, NOAA Headquarters,
Office of Aquaculture

15:30-15:55

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Environmental Change(Moderators: Takuro Shibuno and Mathew Poach)
Oligotrophication and its measures in the Seto Inland Sea, Japan
Katsuyuki Abo, National Research Institute of Fisheries andEnvironment of Inland Sea, FRA

15:55-16:20

Assessment and future prediction of climate shift impacts on the macroalgal ecosystemand cultivation in the Seto Inland Sea
Goro Yoshida, National Research Institute of Fisheries andEnvironment of Inland Sea, FRA
16:20-16:45
Poster session

16:45-17:30

Symposium Reception

17:30-19:30

Tuesday, October 17, 2017
Environmental Remediation(Moderators: Natsuki Hasegawa and Darien Mizuta)
Coastal management using oyster-seagrass interactions for sustainable aquaculture,
fisheries and environment
Masakazu Hori, National Research Institute of Fisheries andEnvironment of Inland Sea, FRA
9:00-9:25
Marine sediment conservation using benthic organisms
Katsutoshi Ito, National Research Institute of Fisheries andEnvironment of Inland Sea, FRA

9:25-9:50

Break

9:50-10:10
Biological Response to Environmental Change(Moderators: Satoshi Watanabe and Brett Dumbauld)

Coastal acidification amplifiers along the US East coast: concerns for shellfish
production
Matt Poach, NOAA, Northeast Fisheries Science Center
10:10-10:35
Growth variation in long blades kelp Saccharina longissima in eastern Hokkaido, Japan
Natsuki Hasegawa, National Research Institute of Aquaculture, FRA
10:35-11:00
Harmful algal blooms and shellfish aquaculture in a changing environment
Leila Basti, Tokyo University of Marine Science and Technology
11:00-11:25
Lunch Break

11:25-13:00
Ecosystem Approach to Aquaculture Part 1(Moderators: Masakazu Hori and Cheng Sheng Lee)

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Ecosystem approach to marine aquaculture
Kay McGraw, NOAA, Office of Habitat Conservation

13:00-13:25

Spatial Planning for Shellfish Aquaculture and Seagrasses in US West Coast Estuaries:
Considerations for Adapting to an Uncertain Climate
Brett Dumbauld, U.S. Department of Agriculture,
Agricultural Research Service
13:25-13:50
Offshore mussel aquaculture: strategies for farming in the changing environment of NE
Atlantic EEZ
Darien Mizuta, NOAA, Northeast Fisheries Science Center
13:50-14:15
Ecosystem Approach to Aquaculture Part 2(Moderators: Katsuyuki Abo and Kay McGraw)
Nutrient environment in Gokasho Bay, effects of fish aquaculture on inorganic nutrient
levelsSatoshi Watanabe, National Research Institute of Aquaculture, FRA
14:15-14:40
Challenges and opportunities of IMTA in Hawaii and beyond
Cheng Sheng Lee, Director, Center for Tropical and Subtropical Aquaculture, U.S.
Department of Agriculture
14:40-15:05
Break

15:05-15:25

Open Discussion: Development of collaborative research projects
Moderators: Fuminari Ito and Mike Rust

15:25-15:50

Science Symposium Closing
Mike Rust, US Panel Chair, NOAA Fisheries Office of Aquaculture

15:50-16:00

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List of ParticipantsAbo, Katsuyuki
Basti, Leila
Bayne, Christopher
Boyce, Delan
Dumbauld, BrettFujii, Tetsuo
Hasegawa, Natsuki
Higano, Junya
Hirose, Taro
Hori, Masakazu
Ikuta, Kazumasa
Ito, Fuminari
Ito, Katsutoshi
Katamachi, Daisuke
Lee, Cheng Sheng
Matsuda, Osamu
McGraw, Kay
Mizuta, Darien
Nakajima, Kazuhiro
Ohkubo, Nobuyuki
Ohseko, Norihisa
Okumura, Takuji
Olin, Paul
Otoshi, Clete
Ozaki, Akiyuki
Poach, Matt
Rust, Mike
Shibuno, Takuro
Shigeta, Toshihiro
Shimada, Yukinori
Takano, Masatsugu
Tezuka, Naoaki
Tokoro, Tatsuki
Uchida, Motoharu
Wang, Shiyu Rachel
Watanabe, Satoshi
Yoshida, Goro

FRA, FEISTUMSAT
FRA, FEISNOAAUSDA, Agricultural Research Service
JIRCAS
NRIA, FRA
FRA, FEIS
FRA, FEIS
FRA, FEIS
FRA, FEIS
FRA, Headquarters
FRA, FEIS
FRA, FEIS
USDA, Center for Tropical and Subtropical Aquaculture
Hiroshima University
NOAA, Office of Habitat Conservation
NOAA, Northeast Fisheries Science Center
FRA, FEIS
FRA, FEIS
FRA, NRIAFRA NRIA,
California Sea Grant
NOAA Headquarters
FRA NRIA,
NOAA, Northeast Fisheries Science Center
NOAA, Headquarters
FRA, NRIA
FRA, FEIS
FRA, NRIAFRA Headquarters
FRA, FEIS
FRA, FEIS
FRA, FEISNOAA, Headquarters
FRA, NRIA
FRA, FEIS

FEIS: National Research Institute of Fisheries and Environment of Inland Sea
FRA: Japan Fisheries Research and Education Agency
NOAA: National Ocean and Atmospheric Administration
NRIA: National Research Institute of Aquaculture
TUMSAT: Tokyo University of Marine Science and Technology
USDA: U.S. Department of Agriculture

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Symposium Abstracts
1. New direction of management policies in the Seto Inland Sea, Japan in the changing
environment
Osamu Matsuda
Hiroshima University (Professor Emeritus), Higashi-Hiroshima, 739-8528, Japan, Email:matsuda036 at go3.enjoy.ne.jp
Abstract
The Seto Inland Sea, the largest enclosed coastal sea in Japan, covers an area of 23,000 km2
and was originally renowned for productive fishing and aquaculture ground with its scenic
beauty. However, since the coastal basin within its watershed around the sea are home to 30
million people, impact of human activities on the sea has been very strong. During Japan’s
period of rapid economic growth in the mid-1960s to mid-1970s, industrialization of the coastal
area, increase of the number of factories and expansion of landfills in water front areas caused
a rapid increase in water pollution with a reduction of shallow water area and destruction of
the marine environment. In order to conserve the environment of the region, the Law on
Temporary Measures for the Environment Conservation of the Seto Inland Sea was enacted in
1973. This law was made permanent in 1978 as the Law on Special Measures for theEnvironment Conservation of the Seto Inland Sea (“The Seto Inland Sea Law”). More than 40
years have passed since the enactment of the legal system in 1973. During the time, changesof both natural and socio-economic environment around the sea were remarkable, and recently,
2015 became the year for a particularly important change of direction for management because
major revisions of both “The Seto Inland Sea Law” and the governmental Basic Program basedon the law were made in this year. In the newly revised Basic Program, two major aims of theprevious Basic Program (1. conservation of water quality, 2. conservation of natural landscape)were reformed to four new major aims (1. conservation and restoration of coastal environment,
2. conservation and appropriate management of water quality, 3. conservation of natural andcultural landscapes, 4. sustainable utilization of fish resources). These recent changes indicatethat not only passive conservation but also positive conservation such as restoration of coastal
environment became very important target nowadays. The new direction of the management
reflects the changing environment of the Seto Inland Sea after WWII in which the first major
target was water pollution control including toxic substances, and then target turned to red tide
due to eutrophication and recently major targets are changing to lowered biologicalproductivity and diversity due to oligotrophication and deteriorated habitat. Therefore, main
approaches of the management also changed from water quality control by restrictive measures
to restoration of habitat such as tidal flat and sea grass bed by promotion of participatory
creative activities. New direction is also supported by the concept of Satoumi which includes
restoration of biodiversity, biological productivity, habitat and well-balanced nutrient cycle by
the intervention of positive human activities. These recent shifts of the management policies
are expected to contribute to recovering productive fishing and aquaculture grounds in the Seto
Inland Sea.
Annotated Bibliography of Key Works
Okaichi, T. and Yanagi, T. ed. 1997., Sustainable Development in the Seto Inland Sea JapanFrom the Viewpoint of Fisheries, 329 pp., Tera Scientific Publishing Company.
This book provides valuable information on the Seto Inland Sea until 1990s.

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Stickney, R. R. and McVey, J.P. ed. 2002. Responsible Marine Aquaculture, 391 pp., CABI
Publishing.
This is a milestone work on the development of sustainable and responsible marine
aquaculture.
Okaichi, T. ed. 2003. Red Tides, 439 pp., Tera Scientific Publishing Company.
This book provides comprehensive aspects of red tides such as phenomena, organism,
ecological problems, environmental relevance and mechanism of outbreaks.
Yanagi, T. 2007. Sato-Umi: A New Concept of Coastal Sea Management, Terra Scientific
Publishing Company, Tokyo.
This book was written by the first proposer of the concept of Sato-Umi (Satoumi).
Matsuda, O. 2008. Eutrophication and its Cause/Consequence: The Case of the Seto InlandSea, p78-92, in Nobuo Mimura ed. “Asia-Pacific Coasts and Their Management”, Springer.
This is a case study on the management of the eutrophic Seto Inland Sea.
Secretariat of the Convention on Biological Diversity (CBD). 2011. Biological and Cultural
Diversity in Coastal Communities – Exploring the Potential of Satoumi for Implementing the
Ecosystem Approach in the Japanese Archipelago, CBD Technical Series No. 61, 118pp.,
Montreal.
This volume of CBD Technical Series provides relevance of Satoumi to biodiversity issue
and case studies of Satoumi activities from Hokkaido northernmost area to Okinawa
southernmost area of Japan.
Matsuda, O. et al. 2012. Western Japan cluster: Seto Inland Sea as satoumi, p381-402, inAnantha Kumar Duraiappah et al. ed. “Satoyama-Satoumi Ecosystems and Human WellBeings”, United Nations University Press.
This is a comprehensive reference of the Seto Inland Sea and also a part of the result of SubGlobal Assessment on Japanese Satoyama and Satoumi.
Matsuda, O. 2012. Combining Activities of Sato-Umi and Sato-Yama in Japan: Towards a
New Type of Integrated Coastal and Watershed Management, in M. Taniguchi and T.
Shiraiwa ed. “The Dilemma of Boundaries-Toward a New Concept of Catchment”, Springer.
This paper describes the possibility of integrated coastal management by connecting SatoUmi and Sato-Yama.
Berque, J. and Matsuda, O. 2013. Coastal Biodiversity Management in Japanese Satoumi.
Marine Policy 39: 191-200.
This paper refers to relevance of Satoumi to biodiversity management.
Matsuda, O. 2014. Predicting and promoting the future state of coastal seas with special
emphasis on Satoumi, p209-221, in Natsuki Shimizu et al. ed. “Connectivity of Hills, Humans
and Oceans, Challenge to Improvement of Watershed and Coastal Environments”, Kyoto
University Press.
Some aspects of future perspective of Satoumi were described in this paper.
2. Marine aquaculture’s role in providing nutritional security in a changing environment
Michael B. Rust
NOAA Office of Aquaculture, 1315 East-West Highway, Silver Spring MD. 20910, USA,
Email: mike.rust at noaa.gov

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Abstract
The world produces less than 2% of its food, fiber and biofuel from the sea despite the fact that
oceans cover 70% of the earth and receive 70% of its solar energy. Instead we use 70% ofavailable freshwater and 40% of our land through agriculture to feed and clothe ourselves.
Future world food security plans developed by governments and international agencies often
focus mainly on improving agriculture with an occasional nod toward fisheries, but rarely
consider what aquaculture, especially marine aquaculture could provide. Marine aquaculture
represents a food production approach that uses less freshwater, feed and land resources thanagriculture, is more energy efficient and emits fewer greenhouse gasses than agriculture. In
addition, marine aquaculture is relatively buffered from some aspects of climate change. For
example, marine aquaculture does not suffer from droughts or floods, and is buffered fromextreme storm events and temperature changes. Properly sited and managed, marine
aquaculture can provide ecosystem services that help wild stocks persist under changing
environmental conditions. Finally, the nutritional quality of aquaculture products is highrelative to terrestrial products, increasing the nutritional quality of the diet for society. Marine
aquaculture needs to articulate the advantages it represents to world nutritional security sodiscussions and planning for future food security under a changing climate can be informed.
Annotated Bibliography of Key Works
U.S. Department of Health and Human Services and U.S. Department of Agriculture. 2015 –2020 Dietary Guidelines for Americans. 8th Edition. December 2015. Available at
http://health.gov/dietaryguidelines/2015/guidelines/.
Every five years the US government reviews current nutritional research and analyzes US
food consumption patterns to develop guidelines. Seafood is chronically under consumed by
all age groups and both sexes. This has real impacts on human health and results in increased
heart disease, stroke and dementia in the US population. Americans consume about half ofwhat is recommended for optimal human health.
Forster, J. and R. Radulovich, 2015. Chapter 11 - Seaweed and food security. In: Tiwari and
Declan, Seaweed Sustainability, Academic Press, San Diego, pp 289- 313.
Makes the case for a marine agronomy based on seaweeds analogous to terrestrial agronomy
that currently provides the majority of our food and fiber.
Hall, S.J., A. Delaporte, M. J. Phillips, M. Beveridge and M. O’Keefe. 2011. Blue Frontiers:
Managing the Environmental Costs of Aquaculture. The WorldFish Center, Penang,
Malaysia.
Provides a comparison between aquaculture and terrestrial production from an environmental
perspective.
3. An overview of NOAA grants on aquaculture and the environment
Shiyu Rachel WangNOAA Headquarters, Office of Aquaculture,1315 East-West Highway, Silver Spring MD.
USA 20910, Email: shiyu.wang at noaa.gov.
Abstract
NOAA funds extramural research on aquaculture and environmental change through threemajor competitive grants: Small Business Innovation Research (SBIR) Program, SaltonstallKennedy (SK) Grant Program and Sea Grant Program. From 2002 to 2016, NOAA has spent8$9.2 million U.S. dollars on research projects focus on the interactions between aquaculture
and the environment, with $6.5 million federal funds and $2.7 million matching funds. Annual
spending fluctuated with a maximum of $1.3 million in 2005 and a minimum of $0.14 million
USD in 2002 and zero spending in 2009. Out of the three major funding programs, Sea Grant
funded 75% of the entire spending. A total of 43 projects on aquaculture and related topics
including nutrient removal, carbon fixation, ocean acidification, waste treatment and related
topics were completed. Analysis of the impact of these projects is planned. An understandingof NOAA’s spending can help identify research gaps, evaluate impact, inform policy andallocate budget related to aquaculture in a changing environment.
Annotated Bibliography of Key Works
Love, D.C., Gorski, I. and Fry, J.P., 2017. An Analysis of Nearly One Billion Dollars of
Aquaculture Grants Made by the US Federal Government from 1990 to 2015. Journal of theWorld Aquaculture Society.
The authors conducted a study on U.S. federal spending for aquaculture by tracking 2957
federal research grants awarded through different agencies from 1990 to 2015. For the pastquarter century, 1.04 billion US dollars were spent on aquaculture research with about 90%
of federal funds and 10% matching funds. Aquaculture production sciences received the mostfunding (27%) out of 13 major disciplines in aquaculture, followed by aquatic animal healthand disease (17%). Environment related aquaculture topics including water and waste
management and environmental interactions received 7% of the total federal funding acrossall related agencies. Comparing the U.S. domestic aquaculture production with the federal
spending, the authors concluded a 37-fold return in federal government investments inaquaculture since 2000. This study can be used as a framework to track and assess federal
agencies’ spending on different topics of aquaculture, identify research gaps and inform
policy making and grant allocation.
4. Oligotrophication and its measures in the Seto Inland Sea, Japan
Katsuyuki Abo1* and Tamiji Yamamoto2
1

National Research Institute of Fisheries and Environment of Inland Sea, Maruishi,
Hatsukaichi, Hiroshima 739-0452, Japan, *Email: abo at fra.affrc.go.jp
2
Hiroshima University, Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8511, Japan
Abstract
The Seto Inland Sea had been known as a beautiful and bountiful sea with rich ecosystem.
However, during the period of high economic growth, eutrophication progressed and fisherydamage caused by harmful algal bloom became frequent. Since the Interim Measures Law
concerning Conservation of the Environment of the Seto Inland Sea (later the Special Measures
Law) was enacted in 1973, the water quality of the Seto Inland Sea has improved by a seriesof measures such as reduction of inflow load. On the other hand, however, oligotrophication
has become a problem in recent years, and it caused decrease in Nori (Pyropia yezoensis)
production due to bleaching of leaves because of nutrient depletion. In addition, it is also
pointed out that the decrease in fisheries production, such as small pelagic fish and demersal
fish, is related to nutrient reduction. Here we describe the changes and current situation in thewater quality of the Seto Inland Sea and discuss the influence of the load reduction on the lower
trophic ecosystem and the fishery production. We also introduce nutrient supply methods suchas fertilizer application, additional discharge of dams, nutrient management operation of

9sewage treatment plants, etc. which are experimentally conducted as countermeasures forbleaching Nori. In addition, we mention future subject to restore the bountiful Seto Inland Sea.
Annotated Bibliography of Key Works
Abo, K., S. Akiyama, K. Harada, Y. Nakaji, H. Hayashi, K. Murata, A. Wanishi, Y.
Ishikawa, T. Masui, S. Nishikawa, K. Yamada, M. Noda and S. Tokumitsu, (accepted) Longterm variations in water quality and causal factors in the Seto Inland Sea, Japan. Bulletin on
Coastal Oceanography, 55
The long-term variations in water quality in the Seto Inland Sea were investigated based on
the routine observation data of the local fisheries experimental stations. The watertemperature increased due to the global warming and the nutrient decreased due tooligotrophication. The reduction of DIN and DIP concentrations were largely affected byland load reduction.
Abo, K., K. Tarutani, K. Harada, K. Miyahara, A. Nakayama and H. Yagi, 2012. Effects ofnutrient discharge on Nori aquaculture area in Kako River estuary, J. JSCE, Ser.B2, Coastal
engineering, 68, 1_1116-1_1120.
Effects of nutrient discharge on Nori aquaculture area were investigated. The Nori productionin the winter season were sustained by nutrient discharge from the river, sewage treatment
plant and industrial effluent. A numerical simulation evaluated the effects of nutrient control
operation of the sewage treatment plant on the nutrient environments of the aquaculture area.
Yamamoto, T., 2002. The Seto Inland Sea––eutrophic or oligotrophic? Marine Pollution
Bulletin, 47, 37-42.
This was the first study showing the Seto Inland Sea was in the state of ‘cultural
oligotrophication’ caused by the reduction of nutrient loading. This study indicated that themeasures to reduce phosphorus had caused a change in phytoplankton species composition,
thereby altering the food web structure, suggesting that this might be the major cause of the
reduction of fishery production.
Yamamoto, T. and G. Hatta, 2004. Pulsed nutrient supply as a factor inducing phytoplankton
diversity. Ecol. Model., 171, 247-270.
A numerical model was constructed to elucidate whether phytoplankton species diversity
could be increased by an environmental fluctuation such as a pulsed nutrient supply. Diatom
showed large fluctuations in cell density in response to pulses of nutrients, while
dinoflagellate showed preference for continuous nutrient supply mode. Dam construction,
which is one of the causes of oligotrophication, usually flattens variability in the freshwater
discharge, hence lead to dinoflagellate dominancy.
Yamamoto, T., S. Tateno, K. Hata, K. Mizushima, Y. Goda, S. Takahashi, K. Tarutani, H.
Saito and T. Tanimoto, 2017. Designing an effective action plan for sustainable local
resources and the coastal environment: A case study of Mitsu Bay, Hiroshima, Japan.
Proceedings of International Conference "Managing risks to coastal regions and communities
in a changing world" (EMECS'11 - SeaCoasts XXVI, St. Petersburg, 22-27.08.2016).
Moscow, RIOR Publ., ISBN978-5-369-01628-2, DOI:
10.21610/conferencearticle_58b43157871ef
This study proposed measures for sustainable fishery production in an oligotrophic bay(Mitsu Bay). Water quality was extremely good (oligotrophic), therefore improvement of
sediment quality was necessary. As oyster cultivation was popular in this bay, improvementof sediment quality using oyster shells could contribute to the formation of a recyclingoriented society.

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5. Assessment and future prediction of climate shift impacts on the macroalgal ecosystemand cultivation in the Seto Inland Sea
Goro Yoshida1*, Hiromori Shimabukuro1, Setsuo Kiyomoto2, Tatsuru Kadota2, Taku
Yoshimura2, Noboru Murase3, Mikio Noda3, Yoshimi Kono4, Shoichi Takenaka4, Toshiharu
Tamura5, Norio Tanada6, Xiaojie Yu7, Naoki Yoshie7 and Xinyu Guo7
1

National Research Institute of Fisheries and Environment of Inland Sea, FRA, Maruisihi,
Hatsukaichi, Hiroshima 739-0452, Japan, *Email: gorogoro at affrc.go.jp
2
Seikai National Fisheries Research Institute, FRA, Taira-machi, Nagasaki, Nagasaki 8512213, Japan
3
National Fisheries University, FRA, Nagata-honmachi, Shimonoseki, Yamaguchi 759-6595,
Japan
4
Fisheries Research Center, Ehime Research Institute of Agriculture, Forestry and Fisheries,
Shitaba, Uwajima, Ehime 798-0104, Japan
5
Ehime Prefectural Government, Ichiban-cho, Matsuyama, Ehime 790-8570, Japan
6
Fisheries Research Division, Tokushima Prefectural Agriculture, Forestry and Fisheries
Technology Support Center, Minami-cho, Kaifu-gun, Tokushima 779-2304, Japan
7
Center for Marine Environmental Studies, Ehime University, Bunkyo-cho, Matsuyama,
Ehime 790-8577, Japan
Abstract
Seto Inland Sea is the largest semi-enclosed sea area, which is interposed to Pacific Ocean by
Bungo and Kii Channels. In the Seto Inland Sea, macroalgal beds are important grounds asnursery of many important fishes and for small scale fisheries such as gill-net or set-net
fisheries. Also, aquaculture of edible macroalgae such as Nori (laver) and Wakame (seamustard), as well as aquaculture of bivalves, is an important industry in the Seto Inland Sea.
However, coastal water temperature on the increase trend in past several decades has been
greatly affecting macroalgal ecosystems and cultivation in western Japan. Abrupt and unsteadydegradation or extinction of macroalgal beds (Isoyake) has been spreading around Japanese
coast, and the phenomena are remarkable along the coasts facing to the open seas (Pacific
Ocean and East China Sea) influenced environmentally by warm currents. Though serious
Isoyake has not still occurred in the Seto Inland Sea, it is also predicted to expand within thesea area in near future as the water temperature continues to rise. In case of aquaculture,
production of Wakame in the Seto Inland Sea has been already tremendously decreasing due tofailure in steady growth of seedlings. All these negative conditions of macroalgae areconsidered to be attributable to physiological unsuitability and conspicuous increase of grazing
activities of herbivorous animals against the background of water temperature increase. We
have been conducting 1) field monitoring and surveys to detect influences of water temperature
increase on macroalgal ecosystems and cultivation, 2) experiments of impacts of watertemperature rise on eco-physiological situations of key species, 3) a construction of an originalhigh resolution numerical model to reproduce and forecast the coastal water temperaturechanges in the past and future, 4) application of the outputs of the model, to relate past events
to temperature conditions at those times for understanding of the mechanisms and to predict
future conditions according to the global warming scenarios, 5) development of practicaltechnologies in macroalgal ecosystem conservation and cultivation for adaptation to changing
environments. In the presentation, we will introduce current situations of macroalgal
ecosystems and cultivation in and around the Seto Inland Sea, and some of the results of thestudies described above.

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Annotated Bibliography of Key Works
Tanaka, K., Taino, S., Haraguchi, H., Prendergast, G. and Hiraoka,. M. 2012. Warming off
southwestern Japan linked to distributional shifts of subtidal canopy-forming seaweeds.
Ecology and Evolution, 2 (11): 2854-2865.
Along the coast of Kochi Prefecture, southwestern Japan, macroalgal bed of temperate kelp
(Ecklonia cava) has been tremendously decreasing and it has serious impact on abalone fishery.
In addition, the authors clarified by field surveys that temperate Sargassum species which arealso important constitutes of macroalgal beds have been replaced by tropical species, S.
ilicifolium. Behind these events, the coastal water temperature has been increasing since the1970s at the rate of 0.3 ℃/ decade in the annual mean.
Takao, S., Kumagai, N.H, Yamano, H., Fujii, M. and Yamanaka, Y. 2015. Projecting theimpacts of rising seawater temperatures on the distribution of seaweeds around Japan undermultiple climate change scenarios. Ecology and Evolution 5 (1): 213-223.
Authors predicted the future distribution of seaweed (temperate kelp, Ecklonia cava) along
the Japanese coast based on water temperature increase prediction output in the most recent
multiple climate projection models and emission scenarios (RCP scenarios). They suggested
that continued warming may cause in a pole-ward shift of the distribution of E. cava, but theresults were different according to the scenarios. In the highest emission scenario (RCP8.5),
E. cava would disappear from the Japanese coast due to both of physiological damages andgrazing pressures by herbivorous animals.
Tanada, N. 2016. Development of a practical method for mass seedling production using
free-living gametophytes and a new cultivar tolerant to warm waters for early harvesting ofUndaria pinnatifida (Harvey) Suringar. Aquabiology 38 (4): 464-471. (in Japanese withEnglish abstract)
The production of Wakame, Undaria pinnatifida in cultivation in Tokushima, which is oneof the largest producing area in Japan, has been decreasing seriously after the 1990s. The
decrease is supposed to be due to water temperature increase, especially during autumn whenseedlings of Wakame are started to be cultured in the sea, because the seedlings are sensitive
to high temperature conditions at that stage. Authors developed new techniques in mass
seedling production and its control, and it can enable to make new cultivars of Wakame
which can have tolerance to high temperatures.
6. Coastal management using oyster-seagrass interactions for sustainable aquaculture,
fisheries and environment
Masakazu Hori1*, Franck Lagarde2, Masami Hamaguchi1 and Mitsutaku Makino3
1

National Research Institute of Fisheries and Environment of Inland Sea, Maruishi,
Hatsukaichi, Hiroshima 739-0452, Japan, *Email: mhori at affrc.go.jp
2
Station de Sete, IFREMER, Sete 34203, France
3
National Research Institute of Fisheries Science, Yokohama, Kanagawa 236-8648, Japan
Abstract
Coastal environments of the world have been exposed to eutrophication for several decades.
Recently the quality of coastal waters has been gradually and successfully improved, however
this improvement has caused another issue in coastal ecosystem services, namely,
oligotrophication. While oligotrophication, with higher water transparency, has recovered12benthic macrophyte vegetation which have been depressed by phytoplankton derived fromeutrophication, local stakeholders have suggested that oligotrophication reduces pelagic
productivity and therefore fishery production in coastal ecosystems. In contrast,
oligotrophication with high transparency has recovered benthic primary productivity including
seagrass vegetation. Seagrasses are quite important for climate change mitigation andadaptation such as carbon storage, acidification mitigation, and protection from sea-level riseand storm surges, which has been welcomed by other stakeholders. Therefore, harmonizing
coastal fishery with environmental conservation goals is now essential for the sustainable useof ecosystem services. Here, we present the scope of our study based on an interdisciplinary
approach including ecological actions, socio-economical actions and psychological actions.
We chose to focus on the interaction between oyster aquaculture and seagrass vegetation as a
typical ecological action. Coastal organisms have adapted their traits to the environment overa long period of time, so that restoration of mixed coastal habitats represents reconstruction of
the original process of coastal production. Subtidal seagrass vegetation with intertidal oyster
reefs is the original mixed habitats in Japan, which would be expected to enhance coastal
production by improving the production efficiency without adding nutrients. A simple field
experiment with carbon and nitrogen contents and the stable isotope analyses revealed thatoyster spats cultivated on a tidal flat adjacent to seagrass beds had higher nitrogen contents andhigher δ13C ratios than spats cultivated in an offshore area using only pelagic production. This
result suggests that utilization of the traditional mixed habitats, which enables oysters to use
both pelagic and various benthic production, has potential to sustain food provisioning service
for humans even in oligotrophic environment.
Annotated Bibliography of Key Works
Pernet, F, N Malet, A Pastoureaud, A Vaquer, C Quere, and L Dubrica. 2012. Marine
diatoms sustain growth of bivalves in a Mediterranean lagoon. J Sea Res, 68: 20-32.
Carbon stable isotopes and fatty acids were measured in the suspended particulate organic
matter (POM) of the Thau lagoon to study its qualitative temporal changes in relation toenvironmental factors and to identify the food sources of bivalves over a one-yr-cycle inrelation to their growth. Reciprocally, the impact of shellfish farming on POM was alsostudied. Oysters and mussels were sampled and measured for biometry, stable isotopes andfatty acid composition. Water samples were collected at two sites, both inside and outside of
the shellfish farming area, to determine concentrations in POM, chlorophyll a (Chl a) andstable isotopes. Carbon isotopes and fatty acids in bivalves reflected seasonal changes in foodsources, which varied consistently with the environment. Seasonal changes in δ13C and fatty
acids in the bivalves suggested that dietary phytoplankton contribution varied according toseason. Terrestrial organic matter and bacteria can contribute to the diet of bivalves during
non-bloom periods. Mussels seemed to rely more on diatoms and less on terrestrial organic
matter and bacteria than oysters did, particularly when phytoplankton biomass was low
during the summer. Although one- and two-yr-old oysters showed similar δ13C, their fatty
acid dynamics differed slightly. Periods of high growth rate in bivalves were mainly fuel led
by diatoms, thus highlighting the importance of seasonal blooms of micro phytoplankton
during the critical period of bivalve growth and gamete production. Although there was no
significant effect of shellfish farms on Chl a and POMδ13C, consistent differences indicatethat stable isotopes could be used successfully to investigate the effects of bivalve
aquaculture.
Morimoto, N, Y Umezawa, ML San Diego-McGlone, A Watanabe, FP Slringan, Y Tanaka,
GL Regino, and T Miyajima. 2017. Spatial dietary shift in bivalves from embayment withriver discharge and mariculture activities to outer seagrass beds in northwestern Philippines.
Mar Biol.164: 84.

13

To investigate the spatial variation in bivalve food sources along a pollution gradient andassess bivalve contribution to biogeochemical cycles in tropical coastal ecosystems, the δ13C
and δ15N values of bivalves and their potential food sources were studied in northwestern
Philippines. In a semi-enclosed embayment affected by river discharge and mariculture
activities, bivalves depended primarily on 13C-depleted suspended particulate organic mattersuch as phytoplankton and/or fish feeds. However, toward the relatively oligotrophic seagrassbeds, the bivalve food source gradually shifted to more 13C-enriched re-suspended and/or
settled particles. Furthermore, in the outer seagrass beds exposed to the open ocean, bivalves
mainly relied on similar food sources, such as detritus of microalgae, regardless of the
distance from the embayment. These trends appear to reflect the ready availability of the foodsources. Especially in the outer seagrass beds, a semi-closed material cycle within the vicinityof the sea bottom likely emerged between bivalves and algae, but not between thephytoplankton in the overlying water column. This resulted in a relatively weak benthicpelagic coupling for bivalves. These cycles would need to be taken into account whenestimating the biogeochemical cycles in eutrophicated coastal areas.
Duarte, CM, IJ Losada, IE Hendriks, I Mazarrasa, and N Marba. 2013. The role of coastal
plant communities for climate change mitigation and adaptation. Nature Climate Change 3:
961-968.
Marine vegetated habitats (seagrasses, salt-marshes, macroalgae and mangroves) occupy
0.2% of the ocean surface, but contribute 50% of carbon burial in marine sediments. Their
canopies dissipate wave energy and high burial rates raise the seafloor, buffering the impactsof rising sea level and wave action that are associated with climate change. The loss of a thirdof the global cover of these ecosystems involves a loss of CO2 sinks and the emission of 1 Pg
CO2 annually. The conservation, restoration and use of vegetated coastal habitats in ecoengineering solutions for coastal protection provide a promising strategy, deliveringsignificant capacity for climate change mitigation and adaption.
7. Marine sediment conservation using benthic organisms
Katsutoshi Ito1*, Mana Ito1, Takeshi Hano1, Toshimitsu Onduka1, Kazuhiko Mochida1,
Nobuaki Shono2 and Ryuhei Nakamura2
1

National Research Institute of Fisheries and Environment of Inland Sea, Fisheries Researchand Education Agency, Maruishi 2-17-5, Hatsukaichi, Hiroshima 739-0452, Japan, *Email:katsuit at affrc.go.jp
2
Biofunctional Catalyst Research Team, RIKEN Center for Sustainable Resource Science(CSRS), 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
Abstract
Estuaries and coastal zones used as fish aquaculture are often polluted by organic contaminants
and anthropogenic chemicals. Bioremediation has been recognized as an efficient technology
to clean up environmental pollutants. The authors have studied environmental remediation
using benthic organisms, and have shown that some annelids are adaptable to polluted
environment. For example, Capitella cf. teleta (Annelida, Polychaeta), inhabits in bottom
sediment beneath a fish farm, has high protease activity, whereas Perinereis nuntia (Annelida,
Polychaeta), inhabits in an estuary has high cellulase activity. Furthermore, Thalassodrilides
cf. briani (Annelida, Oligochaeta) can survive highly hypoxic and sulfidic sediments
contaminated with various pollutants, and have shown to biotransform 1-nitronaphthalene, atoxic and carcinogenic chemical, into substances that are nontoxic to fish. In another study,

14

when the three benthic species were maintained in polluted sediments, the polychaetes P.
nuntia and C. cf. teleta markedly increase redox potential (Eh) level and decrease acid volatilesulfides (AVS) level compared with those of the oligochaete T cf. briani. Furthermore,concentration of polycyclic aromatic hydrocarbons (PAHs), incomplete combustion productsof fossil fuels, in the sediment were significantly lower than the initial level. Especially, T cf.
briani showed a marked ability to degrade the PAHs in the sediment. These results indicatethat benthic organisms have species-specific remediation properties and ecological functions
in organically polluted sediments. Currently, we are working on the development of a real-timemeasuring device of the Eh in the sediment under fish farms. The Eh is a comprehensive
parameter to monitor the degree of eutrophication of the sediment under fish farm. We also
introduce our on-going research progress on this topic.
Annotated Bibliography of Key Works
Ito, K., Nozaki, M., Ohta, T., Miura, C., Tozawa, Y., Miura, T. 2011. Differences of two
polychaete species reflected in enzyme activities. Marine Biology 158 (6): 1211-1221.
Polychaetes constitute most of the benthic macroinvertebrates in estuarine and coastal
environments. We investigated the utilization of organic matter in two polychaete species,
Capitella sp. I and Perinereis nuntia brevicirris, living in different coastal habitats. The
protease activity of Capitella sp. I (89.7 µg/mg) was about 10 times that of P. nuntia
brevicirris (8.0 µg/mg). High cellulase (endo-β-1,4-glucanase) activity was detected in P.
nuntia brevicirris (3.2 µg/mg), whereas scarcely any was detected in Capitella sp. I. We
isolated cDNA clones of protease mRNA from Capitella sp. I and of cellulase mRNA fromP. nuntia brevicirris. The high protease activity of Capitella sp. I enabled it to survive in thesediment under a fish farm, where it degrades organic matter. In contrast, the high cellulase
activity of the estuary-dwelling P. nuntia brevicirris allowed it to degrade organic matter
originating from terrestrial areas.
Ito K, Ito M, Onduka T, Ohta K, Torii T, Hano T, Mochida K, Ohkubo N, Miura T, Fujii K.
2016. Differences in the ability of two marine annelid species, Thalassodrilides sp. andPerinereis nuntia, to detoxify 1-nitronaphthalene. Chemosphere 151: 339-44
Bioremediation is a promising method for remediating environmentally polluted water. We
investigated the abilities of two benthic annelid species to biotransform 1-nitronaphthalene, anitrated polycyclic aromatic hydrocarbon. We used an oligochaete, Thalassodrilides sp.
(Naididae), collected from the sediment beneath a fish farm and a polychaete, Perinereis
nuntia, which was obtained from a commercial source. Populations of both organisms were
exposed to 1400 μg L(-1) of 1-nitronaphthalene in seawater for 3 days in the dark at 20 °C.
The concentration of the pollutant decreased to 12 μg L(-1) in the seawater containing theThalassodrilides sp. and to 560 μg L(-1) in the seawater containing P. nuntia. The 1nitronaphthalene concentration in the bodies of the animals increased from 12 to 94 μg kg(-1)
in Thalassodrilides sp. and from 0.90 μg kg(-1) to 38,000 μg kg(-1) in P. nuntia. After 3days, 99% and 40% of the 1-nitronaphthalene had been biotransformed in theThalassodrilides sp. and P. nuntia experimental groups, respectively. We then tested theacute toxicity of residual 1-nitronaphthalene from the same water using mummichog (fish)larvae. After the larvae had been exposed for 96 h, the percentage of apparently unaffectedlarvae remaining was 83.3% in Thalassodrilides sp. group but only 16.7% in the P. nuntia
group. Clearly, of the two species we studied, Thalassodrilides sp. had a superior ability toconvert 1-nitronaphthalene into substances that were nontoxic to mummichog larvae.
Therefore, we recommend the use of this species for bioremediation of chemically polluted
sediments.

15

Ito M, Ito K, Ohta K, Hano T, Onduka T, Mochida K, Fujii K. 2016. Evaluation ofbioremediation potential of three benthic annelids in organically polluted marine sediment.
Chemosphere 16: 3392-9.
This study aimed to evaluate the possible remedial effects of three marine benthic annelids onorganically polluted sediments from the waters of Hatsukaichi Marina, Hiroshima, Japan.
Two polychaetes, Perinereis nuntia and Capitella cf. teleta, and an oligochaete,
Thalassodrilides sp., were incubated in sediments for 50 days. Their effects on
physicochemical properties such as organic matter (loss on ignition), redox potential (Eh),acid volatile sulfides (AVS), and degradation of polycyclic aromatic hydrocarbons (PAHs)
were assessed. The polychaetes P. nuntia and C. cf. teleta significantly increased Eh leveland decreased AVS level compared with the oligochaete Thalassodrilides sp. and control(without benthic organisms). Total PAH concentration significantly decreased from the initiallevel with all three groups; Thalassodrilides sp. had a marked ability to reduce PAHs insediment. These results indicate that benthic organisms have species-specific remediation
properties and ecological functions in organically polluted sediments.
8. Coastal acidification amplifiers along the US East coast: concerns for shellfish
production
Matthew Poach1*, Daphne Munroe2, James Vasslides3, Ian Abrahamsen4, Sarah Borsetti2 andNicole Coffey5
1

NOAA/NMFS, James J Howard Marine Sciences Laboratory, Highlands, NJ 07732, USA,
*Email: matthew.poach at noaa.gov
2
Rutgers University, Haskin Shellfish Research Laboratory, Port Norris, NJ 08349 USA
3
Barnegat Bay Partnership, Ocean County College, Toms River, NJ 08753
4
University of Pittsburgh, Pittsburgh, PA 15260
5
University of Delaware, Newark, DE 19716
Abstract
In coastal systems endangered by acidified water, it becomes paramount to understand the link
between acidification and its environmental drivers. Bays along the US Mid-Atlantic coast are
particularly vulnerable to local amplification of ocean acidification due to highly eutrophic
conditions, low alkalinity freshwater input, and episodic upwelling of acidified water. To better
understand these drivers two research studies were conducted along the NJ coast. The firststudy was conducted during the summers of 2014 and 2015 at the Aquaculture Innovation
Center (AIC) of Rutgers University located in Cape May, NJ. The AIC is an important research
hatchery that currently supports the New Jersey oyster aquaculture industry through the
production of disease resistant and triploid seed oysters. The second study, which began in thesummer of 2017, focuses on elucidating the range of pH and aragonite saturation (Ωarag)
conditions experienced at the inlet to Little Egg Harbor Bay, NJ, an important shellfish location.
During the summers of 2014 and 2015, temperature, salinity, dissolved oxygen (DO), turbidity
and pH were continuously monitored at the AIC’s intake pipe located in the Cape May Canal.
Periodic duplicate grab samples were also collected at the intake and at locations within thefacility. One of each duplicate grab samples was preserved and analyzed for pH and dissolved
inorganic carbon (DIC), whilst the other was preserved for analysis of the planktonic
community. The DIC and pH were used to calculate the aragonite saturation state of thesampled water. The pH at the intake showed diurnal variations that tended to mirror the DO
signal. The largest drop in pH was measured in July of 2014 and again in July of 2015. These
pH drops were decoupled from the DO signal. Likewise, grab samples showed that water of

16

low pH and aragonite saturation was entering the facility. The occurrence of consistentSouthwesterly winds and cooler surface water temperatures along the coast during both timeframes indicated that upwelling was occurring. A spike in plankton numbers was recorded insamples collected immediately after the 2014 upwelling event. These results show that
hatcheries along the NJ coast need to be aware that upwelling may bring reduced shellfish
production conditions, and highlights the need for continued monitoring. Starting in May of2017, temperature, salinity, DO, turbidity, pH and carbon dioxide partial pressure (pCO2) were
continuously monitored at one station in Little Egg Harbor off Beach Haven. Periodic grab
samples were collected from near the sensors, preserved, and analyzed for pH and DIC. Resultsfrom the grab samples were used to validate sensor readings. Sensor temperature, salinity, pH
and pCO2 data were used to calculate Ωarag. Relationships between pH and DO will behighlighted as well as indications of periodic upwelling events. Results will be used todetermine the relative contribution of eutrophication, freshwater inflow, and coastal upwellingas acidity amplifiers as well as estimate past pH and Ωarag levels from legacy data collected in
nearby Barnegat and Great Bays.
Annotated Bibliography of Key Works
Barton, A., B. Hales, G.G. Waldbusser, C. Langdon, and R.A. Feely. 2012. The Pacificoyster, Crassostrea gigas, shows negative correlation to naturally elevated carbon dioxidelevels: Implications for near-term ocean acidification effects. Limnology and Oceanography,
Vol 57: 3. Pp 698–710.
The authors report results of a monitoring study designed to evaluate the response of Pacificoyster (Crassostrea gigas) larvae, grown at a commercial hatchery on the Oregon coast, tonatural changes in carbonate chemistry associated with periodic seasonal upwelling during
the summer of 2009. During the study, the intake waters experienced aragonite saturation
states from 0.8 to 3.2 and pH from 7.6 to 8.2. They observed significant negative
relationships between aragonite saturation states at the time of spawning and subsequent
growth and production of larvae over the size range of 120 to 150-mm shell length. This was
one of the first studies to link failures in seed oyster production to more corrosive water fromcoastal upwelling.
Booth, J.A.T., E.E. McPhee-Shaw, P. Chua, et al. 2012. Natural intrusions of hypoxic, low
pH water into nearshore marine environments on the California coast. Continental Shelf
Research, Vol 45: 15. Pp 108–115.
The authors reviewed a decade-long data set to examine oxygen and pH variability on the
inner shelf off of Central California. Results show regular inundation of cold, hypoxic andlow pH water. The source-water for these periodic intrusions originates in the offshore,
midwater environment above the local OMZ, generally between 50–100 m but occasionallydeeper. Pulses of the greatest intensity arose at the onset of the spring upwelling season, andfluctuations were strongly semidiurnal and diurnal. Arrival of cold, hypoxic water on the
inner shelf appears to be driven by tidal-frequency internal waves pushing deep, upwelledwater into nearshore habitats. These observations are consistent with the interpretation thathypoxic water is advected shoreward from the deep, offshore environment where water
masses experience a general decline of temperature, oxygen and pH with depth.
Ekstrom, J.A., L. Suatoni, S.R. Cooley, et al. 2015. Vulnerability and adaptation of US
shellfisheries to ocean acidification. Nature Climate Change, Vol 5: 3. Pp 207–214.
Authors present a spatially explicit, multidisciplinary analysis of the vulnerability of coastal
human communities in the United States to ocean acidification. Their results highlight USregions most vulnerable to ocean acidification, reasons for that vulnerability, important
knowledge and information gaps, and opportunities to adapt through local actions. Results

17

indicated that 16 of the 23 bioregions around the United States are exposed to rapid OA(reaching ΩAr 1.5 by 2050) or at least one amplifier; 10 regions are exposed to two or morethreats of acidification. The marine ecosystems and shelled molluscs around the PacificNorthwest and Southern Alaska are expected to be exposed soonest to rising global OA,
followed by the north-central West Coast and the Gulf of Maine in the northeast UnitedStates. Communities highly reliant on shelled molluscs in these bioregions are at risk fromOA either now or in the coming decades. In addition, pockets of marine ecosystems along theEast and Gulf Coasts will experience acidification earlier than global projections indicate,owing to the presence of local amplifiers such as coastal eutrophication and discharge of lowΩAr river water. This analysis can be used to help prioritize societal responses to ocean
acidification.
Gobler, C.J. and H. Baumann. 2016. Hypoxia and acidification in ocean ecosystems:
coupled dynamics and effects on marine life. Biological Letters, Vol 12: 5. Pp 1-8.
As climate change progresses, the effects of atmospheric CO2 on coastal acidification will
intensify; and, while hypoxia is a much-studied stressor for coastal organisms, the combined
effect of hypoxia and acidification has only recently become a focus for scientists. The
authors conduct a meta-analysis of published research that studied the combined effects ofpH and dissolved oxygen variability on marine organisms. The authors conclude that low DO
is a greater stressor to most marine organisms than low pH conditions, although worse effects
can occur through the synergistic interaction of the two. While most traits under concurrent
low DO and low pH appeared to be additively affected, every study reviewed also foundsynergistic interactions in at least one instance. They also conclude that neither theoccurrence nor the strength of these synergistic impacts is currently predictable, andtherefore, the true threat of concurrent acidification and hypoxia to marine food webs andfisheries is still not fully understood. Addressing this knowledge gap will require an
expansion of multi-stressor approaches in experimental and field studies.
Wallace, R.B., H. Baumann, J.S. Grear, R.C. Aller, and C.J. Gobler. 2014. Coastal ocean
acidification: The other eutrophication problem. Estuarine, Coastal and Shelf Science, Vol148: 5. Pp. 1-13.
To assess the potential for acidification in eutrophic estuaries, the authors characterized thespatial and temporal patterns of DO, pH, pCO2, and ΩAragonite in four, semi-enclosed estuarine
system across the Northeast US: Narragansett Bay, Long Island Sound, Jamaica Bay, andHempstead Bay. Multi-year monitoring datasets were assessed to define seasonal patterns in
pH and DO while cruises were conducted to vertically and horizontally resolve spatial
patterns of acidification during the seasonal onset, peak, and decline of hypoxia in theseestuaries. They utilized three approaches for this study: 1) The analysis of monthly
monitoring data across Long Island Sound; 2) Vertical measurements of water column
conditions across Narragansett Bay, Long Island Sound, and Jamaica Bay; and 3)
Continuous, horizontal mapping of conditions across Jamaica Bay and Hempstead Bay. Low
pH conditions (<7.4) were detected in all systems during summer and fall months concurrent
with the decline in DO concentrations. While hypoxic waters and/or regions in close
proximity to sewage discharge had extremely high levels of pCO2, (>3000 µatm), were acidic
pH (<7.0), and were under-saturated with regard to aragonite (ΩAr < 1), even near-normoxic
but eutrophic regions of these estuaries were often relatively acidified (pH < 7.7) during latesummer and/or early fall. This study revealed that acidification is an annual feature ofeutrophic estuaries across the Northeast US that co-occurs with seasonally low oxygen. The
spatial and temporal dynamics of DO, pH, pCO2, and ΩAragonite suggest that they are allultimately driven by high rates of microbial respiration. The degree of acidification observed

18

in these systems during summer are within ranges that have been shown to adversely impact
a wide range of marine life.
9. Growth variation in long blades kelp Saccharina longissima in eastern Hokkaido, Japan
Natsuki Hasegawa1*, Toshihiro Onitsuka2, Sayaka Ito2 and Tomonori Azumaya2
1

National Research Institute of Aquaculture, Japan Fisheries Research and Education
Agency, 422-1, Nakatsuhamaura, Minamiise, Watarai, Mie, 516-0193, Japan, *E-mail:hasena at affrc.go.jp
2
Hokkaido National Fisheries Research Institute (Kushiro Laboratory), Japan Fisheries
Research and Education Agency, 116 Katsurakoi, Kushiro, Hokkaido, 085-0802, Japan
Abstract
Saccharina longissima (Naga-konbu in Japanese) is one of commercially important
Laminariacean kelp species, which grows to more than 10 m in blade length. The kelp is
distributed in shallow Pacific coastal areas from eastern Hokkaido (Kushiro and Nemuro) to
the Chishima island. Its distribution area is under the influence of the cold Oyashio current,
and the water temperature varies seasonally from sub-zero to 20°C. This kelp is the main
harvested species in eastern Hokkaido, mostly used for tsukuda-ni (preserved food cooked withsweetened soy sauce) and kelp rolls making use of its soft texture, whereas other kelp species
with harder blades are widely used for broth. Its annual production is around 10 thousand tons
in dry weight with a gradual decreasing trend in recent years. Fisheries cooperative associationof Habomai in Nemuro has been monitoring the blade size of the kelp in its harvested grounds
along the coastal line of more than 15 km (43.30°N, 145.67°E - 43.39°N, 145.82°E) in May
and June. We analyzed the variations in the blade size of the kelp (Age 1+) in this area between
2000 and 2014. S. longissima is a perennial kelp species, and the kelp over Age 1+ is targeted
for fisheries harvesting using long handle gears between June and October. Effects of locational
environmental factors on the blade weight in May and June were estimated using correlation
analysis and generalized linear regression model (GLM). In GLM analysis of weight in May,
monthly average water temperature in Kushiro, monthly average daylight hours and windspeed in Nemuro for the previous two years and longitudes at sampling points were used as
explanation variables. In GLM analysis of weight in June, monthly average environmental
parameters in May and June were used as explanation and the average blade weight in eachpoint in May as both explanation and offset variables. The monitoring data showed that theblade size varied among years, and the blade growth was good in 2002 and 2009. On the other
hand, 2003, 2011 and 2013 had a poor-growth of the blade. Correlation analysis revealed that
only correlation coefficients between the blade weight in May and water temperature had
regular trends: negative during the previous year and positive during the present year. GLM
analysis of the blade weight in May also revealed that the models including only temperaturesand longitudes had small AIC values of 6,346 although AICs of Null and best model including
all parameters were 6,513 and 6,306 (smallest), respectively. GLM analysis of the blade weightin June revealed that the average blade weight at each study point remarkably contributed to
predict the weight in June. These results suggested that the growth of S. longissima is affectedby the water temperature. High water temperature in the previous autumn and extremely low
temperature in the present winter to spring reduce the growth of the kelp. The increasing trendsof water temperature in recent years, may be one of the factors decreasing the fisheries
production of the kelp in eastern Hokkaido.
Annotated Bibliography of Key Works

19

Sasaki Shigeru. 1973. Studies on the life history of Laminaria angustata var. longissima (M.)
Miyabe. Hokkaido Kushiro Fisheries Experimental Station, Kushiro. Pp141.
This paper was published in 1970s when this species increasingly became of high fisheries
importance around eastern Hokkaido, Japan. The author summarized the life history of
Laminaria angustata var. longissima (M.) Miyabe., which has been recently renamed as
Saccharina longissima. This paper includes the studies about the life history of two seasonal
germinal groups in winter and summer to provide information for stock enhancements, theimportance of suspended culture, reviewing position of the S. longissima in Japanese kelp
fisheries with evaluating the factors affecting its fisheries production such as the floating ice.
Some parts of these studies were published in Journal of Hokkaido Fisheries Experimental
Station in Japanese. Although the marine and social environments for S. longissima fisheries
have markedly changed since 1970s, intensive studies such as one done by Sasaki (1973)
have not been conducted since then.
Yotsukura Norishige. 2010. The hierarchy of Laminariales in Japan. Algal Resources, 3:193198.
This paper reviews the hierarchy of laminarialean algae which has been proposed bymolecular phylogenetic analyses. There is a variety of laminarialean species in Japan’s
coastal areas where some species including Saccharina longissima are harvested or cultured
on a large scale. These species have been classified based on morphological characteristics
although there are variations in its morphology among its growth stages and environmental
conditions. Author enumerated 37 laminarialean species belonging to 7 families in Japan.
10. Harmful algal blooms and shellfish aquaculture in a changing environment
Leila Basti1*, Kiyohito Nagai2, Susumu Segawa3, Yuji Tanaka1, Toshiyuki Suzuki4 andSatoshi Nagai4
1

Department of Ocean Sciences, Tokyo University of Marine Science and Technology,
Minato, Tokyo 108-8477, Japan. *E-mail: lbasti1 at kaiyodai.ac.jp
2
K. Mikimoto & Co. Ltd., Osaki Hazako, Hamajima-Cho, Shima, Mie 517-0403, Japan3
Department of Aqua Bioscience and Industry, Tokyo University of Agriculture, 196 Yasaka,
Abashiri 099-2493, Japan
4
National Research Institute of Fisheries Science, Japan Fisheries Research and Education
Agency, 2-12-4 Fukuura, Kanazawa, Yokohama, Kanagawa 236-8648, Japan
Abstract
Shellfish aquaculture is mainly carried out in sheltered coastal areas that are affected by several
anthropogenic stressors including eutrophication, pollution, biofouling, invasive species,
expanding diseases, and harmful algal blooms. In particular, harmful algal blooms (HAB) havebeen known to cause fish and shellfish kills, contamination of fish but mainly shellfish withpotent toxins that cause mild to severe poisonings in humans, and in many cases alteration of
ecosystem function. In shellfish, notably in bivalve molluscs, in addition to mass mortalities,
HAB are known to cause acute to chronic physiological and pathological alterations that leadto impediments to aquaculture farms via reduction of their fitness or following closure of
production due to long-term contamination with toxins detrimental to human health. The
frequency, magnitude, duration and in several cases the geographic distribution of HAB havebeen increasing putting shellfish aquaculture farms under further stress. Several factors havebeen attributed to such increase in HAB, including climate change, with recent reports of range
expansion of some cosmopolitan HAB species across the North Atlantic and North Pacific20

associated with warming ocean temperature and with projected range expansion of some othercosmopolitan HAB species across the North Western European Shelf-Baltic Sea system andNorth East and South East Asia associated with increased nutrient loads under projectedclimate change scenario A1B of the IPCC, IPSL-CM4. Warming water temperature driven byclimate change is also expected to induce thermodynamic changes in physiological functionsof shellfish with potential shifts in their thermal sensitivity and performance, as it is also
expected to alter the responses of bivalves to HAB. In the present study, the effects of warming
temperature and several HAB species of major concern to shellfish aquaculture farms both inJapan and around the world, on the economically-important bivalve species Manila clam
(Ruditapes philippinarum), Mediterranean mussel (Mytilus galloprovincialis), Pacific oyster(Crassostrea gigas), Japanese pearl oyster (Pinctada fucata martensii), Japanese scallop(Mizuhopecten yessoensis) and noble scallop (Mimachlamys nobilis), are presented. The
effects of warming temperature and the HAB species Heterocapsa circularisquama (shellfishkills), Alexandrium catenella (paralytic shellfish poisoning, PSP) and A. affine(uncharacterized allelochemicals), Chattonella marina, Chattonella antiqua and Heterosigma
akashiwo (ichthyotoxic, fish- and shellfish-kills), Karenia mikimotoi and K. papilionacea(Fish- and shellfish-kills), and Dinophysis acuminata and D. caudata (diarrheic shellfish
poisoning DSP, and other lipophilic toxins) have been examined. The results of several
experimental sets on behavior, feeding, respiration, absorption efficiency, scope for growth,organ integrity, oxidative stress, and survivorship of adult bivalves are presented. In addition,
the effects on gametes (oocytes and spermatozoa) and early-life developmental stages(fertilization, fertilized eggs, embryos, several larval stages) are also presented and discussed.
The combined effects of HAB and ocean warming – and other climate driven stressors, notably
ocean acidification – on these important cultured shellfish species will be discussed in light of
the finding of the present study and other relevant studies reported in the literature.
Annotated Bibliography of Key Works
Glibert, P.M., Allen, J.I., Artioli, Y., Beusen, A., Bouwan, L., Harle, J., Holmes, R., Hotl, J.,
2014. Vulnerability of coastal ecosystems to changes in harmful algal bloom distribution in
response to climate change: projections based on model analysis. Global Change Biol. 20:
3845–3858.
Using a global modeling approach, the effects of nutrient loading and climate change on the
projected distributions of two genera of harmful algae in coastal ecosystems of three regionsof the globe were examined. Range expansions and retractions were found for the two genera
suggesting future shifts in the vulnerability of coastal ecosystems to HAB events, increased
regional HAB impacts on aquaculture leading to increase in the risks to human health andecosystem services and associated economic consequences.
Basti, L., Endo, M., Segawa, S., Shumway, S.E., Tanaka, Y., Nagai, S., 2015. Prevalence andintensity of pathology induced by the toxic dinoflagellate, Heterocapsa circularisquama, inthe Mediterranean mussel, Mytilus galloprovincialis. Aquat. Toxicol. 163: 37–50.
The study examines the effects of temperature on the pathologies induced by the shellfishkilling harmful alga, Heterocapsa circularisquama, in the Mediterranean mussel, Mytilus
galloprovincilias. The study shows that increased temperature leads to increased prevalence
and intensity of pathologies in the mussels in several vital organs, including gills andintestines. The study shows that warming temperature may increase the effects of the harmful
alga on mussels even at low cell density, possibly reducing the overall health of the mussels.
It also shows that the range expansion of the harmful alga associated with increased winterwater temperature may put bivalve aquaculture farms under further risks of mass mortalities
and production failure.

21

Filgueira, R., Guyondet, T., Comeau, L.A., Tremblay, R., 2016. Bivalve aquacultureenvironment interactions in the context of climate change. Global Change Biol. 22: 3901–
3913.
The study examines the interactions between bivalve aquaculture and the environment (baygeomorphic type, freshwater input), in the context of climate change (sea level rise,temperature, precipitation). Based on a factorial deign of 336 scenarios, the modeling showedthat temperature is the strongest climate change driver to affect bivalve aquaculture as it can
influence their metabolism. Differences in thermal tolerance of the cultured bivalve species
would determine “winners” from “losers”.
Gobler, J.C., Dohrty, O.M., Hattenrath-Lehmann, T.K., Griffith, A.W., Kang, Y., Litaker,
R.W., 2017. Ocean warming since 1982 has expanded the niche of toxic algal blooms in the
North Atlantic and North Pacific oceans. P. Natl. Acad. Sci. USA 114: 4975–4980.
The study models the trends in growth rates and duration of bloom seasons of two species ofthe most toxic and widespread harmful algal blooms in the North Atlantic and North Pacificoceans using high-resolution SST (sea surface temperature) over the past three decades.
Increasing water temperature associated with climate change have expanded the niches ofthese toxic algae (Dinophysis auminata and Alexandrium fundeyense) and might contribute toan expansion of the associated human health threat via the consumption of shellfish
contaminated with diarrheic shellfish poisoning (DSP) and paralytic shellfish poisoning(PSP).
11. Ecosystem approach to marine aquaculture
Katherine A. McGraw* and Michael B. Rust
NOAA Office of Aquaculture, 1315 East-West Highway, Silver Spring MD. USA 20910,*Email: kay.mcgraw at noaa.gov
Abstract
The increase in world population, along with increased demand for seafood as a source ofhuman nutrition, and stagnant wild fisheries catches, will necessitate the growth anddiversification of marine aquaculture globally. However, marine aquaculture development inmany countries, including the United States, lags behind that of freshwater aquaculture. The
United States, despite having the world’s largest Exclusive Economic Zone (EEZ), imports
about 90 percent of the seafood consumed domestically (by value). One solution to the seafood
import deficit is to pursue the development of offshore aquaculture in the EEZ, or federalwaters. Various laws and regulations give the National Oceanic and Atmospheric
Administration (NOAA) oversight of fisheries in federal waters. NOAA’s national Marine
Fisheries Service (NOAA Fisheries) has long recognized the importance of implementing
ecosystem-based aquaculture management in order to explicitly account for environmental
changes and make trade-off decisions for actions that affect multiple species. If marine
aquaculture is to grow in an environmentally and economically sustainable way, there need to
be guidelines and a framework for this effort, just as there are for offshore capture fisheries.
The concept of an ecosystem approach to aquaculture management embodies these principles.
In order to provide a framework for offshore aquaculture in the United States, the NOAA
Office of Aquaculture is developing an Ecosystem Approach to Aquaculture (EAA), which
will serve as the first step in designing a more detailed, comprehensive plan for implementationof ecosystem-based management of offshore aquaculture. Similar to NOAA Fisheries’
definition for ecosystem-based fisheries management, the NOAA Office of Aquaculture22

defines EAA as: “a systematic approach to aquaculture management in a geographicallyspecified area that contributes to the resilience and sustainability of the ecosystem; recognizes
the physical, biological, economic, and social interactions among the affected aquaculturerelated components of the ecosystem, including humans; and seeks to optimize benefits among
a diverse set of societal goals.” The purpose of the EAA is to enable the development ofsustainable marine aquaculture within the context of the National Oceanic and Atmospheric
Administration’s (NOAA) multiple stewardship missions and broader social and economic
goals. Meeting this objective will require NOAA to integrate environmental, social, andeconomic considerations in management decisions concerning aquaculture. The EAA will also
serve to reaffirm that aquaculture is an important component of NOAA’s efforts to maintainhealthy and productive marine and coastal ecosystems. This includes protecting special marine
areas, rebuilding overfished wild stocks, restoring populations of endangered species, andrestoring and conserving marine and coastal habitats. Implementation of the EAA involves
balancing competing uses of the marine environment, creating employment and business
opportunities in coastal communities, and enabling the production of safe and sustainableseafood. This presentation will provide an overview of NOAA’s Ecosystem Approach to
Aquaculture, including a definition of EAA, rationale for development of the document, andsome of the benefits of EAA.
Annotated Bibliography of Key Works
Soto, D., Aguilar-Manjarrez, J., Hishamunda, N. (eds). Building an ecosystem approach toaquaculture. FAO/Universitat de les Illes Balears Expert Workshop. 7–11 May 2007, Palmade Mallorca, Spain. FAO Fisheries and Aquaculture Proceedings. No. 14. Rome, FAO. 2008.
221 pp.
This FAO report summarizes findings from a workshop co-organized with the Universitat deles Illes Balears that took place from 7–11 May 2007 in Palma de Mallorca, Spain on“Building and ecosystem approach to aquaculture” (EAA). Participants defined the phrase“ecosystem approach to aquaculture” and several main principles that should guide thesustainable development of aquaculture. These included the development of aquaculture
consistent with resilience of ecosystem functions; improving human wellbeing; andconsideration of other relevant sectors (social, technical, economic, and political). They statethat EAA should address the many needs and desires of societies without compromisingecological integrity. The workshop participants also agreed on various ecosystem approaches
for different scales (e.g., small or “farm”, regional or zone, and global) and that regulations
should focus more on the recipient body of water (e.g., stream, estuary, large marine
ecosystems) rather than the scale and intensity of production.
Aguilar-Manjarrez, J., Soto, D. and Brummett, R. 2017. Aquaculture zoning, site selection
and area management under the ecosystem approach to aquaculture. Full document. Report
ACS113536. Rome, FAO, and World Bank Group, Washington, DC. 395 pp.
The Food and Agricultural Organization of the United Nations and the World Bank Group
convened an expert workshop on Site Selection and Carrying Capacities for Inland andCoastal Aquaculture in December 2010 in Northern Ireland. Spatial planning is becoming
increasingly important in the growth of aquaculture and the issues involved require an
ecosystem approach to management that addresses larger spatial units than just the individual
farm or site. The main purpose of the workshop was development of a guide or handbook foraquaculture site selection and carrying capacity estimation within an ecosystem approach toaquaculture that can be used by a broad range of stakeholders. The publication provides
useful and practical information and guidance for managers, policy-makers, technical staff,
and aquaculturists about zoning, siting, and management based on experiences and examples

23

from ten case studies in countries around the world. They identify relevant processes andactivities for various users on different spatial scales in a systematic fashion.
National Oceanic and Atmospheric Administration. 2016. Ecosystem-based fisheries
management policy of the National Marine Fisheries Service. National Marine FisheriesService Policy Directive 01-120. May 23, 2016. 8 pp.
Several national laws or mandates require the National Oceanic and Atmospheric
Administration (NOAA) to manage the nation’s living marine resources, including fisheries
in a sustainable manner. In order to enable better decision-making among various groups andconcerns, (e.g., commercial, recreational, and subsistence fisheries), aquaculture, protected
species, biodiversity, and habitats, NOAA is implementing Ecosystem-Based Fisheries
Management (EBFM). The policy directive issued in May 2016 is a framework for an
ecosystem approach to fisheries, which defines EBFM; describes the benefits of EBFM;
discusses how EBFM relates to existing legal authorities and requirements; and establishes aframework of guiding principles for implementing EBFM within NOAA Fisheries. It builds
on the NOAA’s past progress and commitment to integrating its management programs forliving marine resources and considering interactions among fisheries, protected species,
aquaculture, habitats, and other ecosystem components, including human communities indecision-making. The policy defines EBFM as “a systematic approach to fisheries
management in a geographically specified area that contributes to the resilience andsustainability of the ecosystem; recognizes the physical, biological, economic, and social
interactions among the affected fishery-related components of the ecosystem, including
humans; and seeks to optimize benefits among a diverse set of societal goals.” The EBFM
policy document specifically mentions aquaculture as an ecosystem component, and NOAA
includes aquaculture in the term “fisheries”. Therefore, this document although mostly
intended for commercial fisheries, forms the basis for the development of a separate
Ecosystem Approach to Aquaculture (EAA) which recognizes the similarities, but also the
distinct differences, between “capture” or “wild” fisheries and aquaculture. Although the
EBFM directive focuses on “capture” or “wild” fisheries, the language and concepts in it arealso directly applicable to aquaculture and, in most instances, the phrase “ecosystemapproach to aquaculture”, or EAA could easily be substituted for “ecosystem-based fishery
management” (EBFM), and the word “aquaculture” substituted for “fisheries”.
Since there are distinct and important differences between capture fisheries and aquaculture,
the NOAA Office of Aquaculture is developing a separate Ecosystem Approach to
Aquaculture (EAA). An EAA is the first step or level along a continuum toward a more
complex and detailed plan for implementing ecosystem-based management of aquaculture.
National Oceanic and Atmospheric Administration. 2011. Marine Aquaculture Policy.
NOAA Office of Aquaculture. Issued June 2011.
The NOAA Office of Aquaculture developed a Marine Aquaculture Policy in 2011 to enable
the development of sustainable marine aquaculture within the context of NOAA’s multiple
stewardship missions and legal mandates. The document defines aquaculture as “thepropagation and rearing of aquatic organisms for any commercial, recreational, or public
purpose”. It includes production for food, wild stock replenishment or restoration (for finfish
as well as shellfish and other marine organisms), and rebuilding populations of threatened or
endangered species. It contains specific goals with regard to aquaculture development andmanagement, and provides the basis for the policy and some background information. The
policy also describes the benefits and challenges of sustainable aquaculture in the U.S. andsets forth NOAA aquaculture priorities and actions for implementing the policy in terms ofregulations, interactions with various agencies and groups in the U.S., and cooperation withother nations. One of the stated goals in the policy is ecosystem compatibility; that is to say,

24

aquaculture development in federal waters should be compatible with the functioning ofhealthy, productive, and resilient marine ecosystem. In keeping with this goal, aquaculture
operators should be held accountable for protecting the species and environment in which
they are working. Other goals include compatibility of aquaculture facilities with otherauthorized uses of marine waters and basing management decisions on the best available
science and information.
12. Spatial Planning for shellfish aquaculture and seagrasses in US west coast estuaries:
considerations for adapting to an uncertain climate
Brett R. Dumbauld1*, Jennifer L. Ruesink2 and George G. Waldbusser3
1

USDA-ARS, Hatfield Marine Science Center, Newport, OR 97365, USA, *Email:brett.dumbuld at ars.usda.gov
2
Department of Biology, University of Washington, Seattle, WA 98195, USA
3
College of Earth, Ocean and Atmospheric Sciences, Oregon State University, Corvallis, OR
97365 USA
Abstract
Shellfish aquaculture has been an important contributor to the local economy of several
communities along the US West Coast for almost 100 years and in most of the estuaries where
it occurs it has coexisted with the native seagrass (eelgrass, Zostera marina). Eelgrass provides
numerous ecosystem services including nursery habitat for juvenile fish and invertebrates, but
is declining in many locations worldwide, and is therefore now protected by no net loss
provisions in US laws and regulations. We have studied the interaction between oyster
aquaculture and eelgrass at both the local process scale and at the estuarine landscape scale in
Willapa Bay, Washington. While there are important differences, most US West coast estuaries
like Willapa Bay are small relative to the nearby coast, experience less riverine influence thanestuaries where oysters are cultured on eastern edges of continents, and the majority of culture
takes place in intertidal areas. The ecology of eelgrass and cultured Pacific oysters as well as
their role as habitat is thus directly influenced by bathymetry and proximity to the coastal ocean.
We summarize studies on the interaction between eelgrass and oyster culture at local scales,present data that suggest culture practices are important to consider, but the cumulativeinteraction is not necessarily negative for eelgrass at the estuarine landscape scale in Willapa
Bay. We also summarize studies on the influence of sea level rise (SLR) and sea waterchemistry (ocean acidification, OA), two projected changes in climate that are expected tooccur over a broader spatial and longer temporal scale. SLR is projected to enhance thepresence and interaction of eelgrass with oyster aquaculture in Willapa Bay, though this effectwas mostly driven by bathymetry in our simplistic model and landward eelgrass expansion
could be restricted elsewhere. OA has already influenced oyster culture especially incommercial hatcheries where it changes aragonite saturation state and the ability of larval
oysters to deposit shell. Evidence for direct effects of carbonate chemistry in estuaries like
Willapa Bay is more equivocal due to complex interactions, yet still related to the proximity ofthe ocean and cold upwelled water which also influences natural spawning on this coast. The
presence of eelgrass may also buffer water chemistry at least over short time scales, but is lesslikely to affect juvenile oysters and may impact oyster growth by reducing water flow. Thesephysical effects of structure also influence conspecific eelgrass plants and appear to be more
important than water chemistry feedbacks. Recent initiatives to expand shellfish aquaculture
in US west coast estuaries have received increased regulatory scrutiny due in large part to thisinteraction with eelgrass. Our data and review suggests that in addition to a permit process that

25

simply evaluates and prevents direct negative effects of oyster culture on eelgrass at small
spatial and immediate temporal scales, managers should consider a broader adaptive approachthat considers bathymetric and along estuary gradients that affect both of these resources andthe services they provide, especially given the uncertainty of future climate.
Annotated Bibliography of Key Works
Barton, A., G.G. Waldbusser, R.A. Feely, S.B. Weisberg, J.A. Newton, B. Hales, S. Cudd, B.
Eudeline, C.J. Langdon, I. Jefferds, T. King, A. Suhrbier, and K. McLaughlin. 2015. Impacts
of coastal acidification on the Pacific northwest shellfish industry and adaptation strategies
implemented in response. Oceanography 28: 146-159.
This is the most recent review of the history and science underpinning the effects of changing
seawater chemistry on bivalve shellfish larvae and the impacts that have already taken place
to the commercial shellfish aquaculture industry on the US West Coast. Multiple authors
contributed to this review which addresses a broad audience but covers the leading researchon direct effects to bivalve larvae as well as monitoring seawater conditions and adapting tothese changes.
Dumbauld, B.R., and L.M. McCoy. 2015. The effect of oyster aquaculture on seagrass(Zostera marina) at the estuarine landscape scale in Willapa Bay, Washington (USA).
Aquaculture Environment Interactions, 7: 29-47.
The authors groundtruthed and analyzed aerial photographs taken in three separate years tobuild spatial layers for seagrass cover in Willapa Bay, Washington, USA. They createdspatial layers for shellfish aquaculture and several other factors such as distance to theestuary mouth and intertidal bathymetry that could influence eelgrass and then built a model
to evaluate eelgrass cover in areas outside of shellfish aquaculture beds. This model was used
to predict expected values within aquaculture beds and compare this with actual values toestimate the effect of aquaculture. The approach is unique in that it examined effects at theestuary scale and over several years and the authors have submitted a second manuscript thatuses a similar approach to assess sea level rise.
Dumbauld, B.R., J.L. Ruesink, and S.S. Rumrill. 2009. The ecological role of bivalve
shellfish aquaculture in the estuarine environment: A review with application to oyster andclam culture in West Coast (USA) estuaries. Aquaculture, 290: 196-223.
The authors review the role of shellfish aquaculture in US West Coast estuaries. Whilesubsequent studies have clarified this role and the interaction between shellfish culture andother estuarine habitats like seagrass, general conclusions remain the same and suggest thatmost forms of shellfish culture as currently practiced have only short-term impacts in West
coast US estuaries and habitats like eelgrass are generally resilient to these changes.
Hales, B., A. Suhrbier, G.G. Waldbusser, R.A. Feely, and J.A. Newton. 2017. The carbonate
chemistry of the "fattening line," Willapa Bay, 2011-2014. Estuaries and Coasts, 40: 173186.
The authors present detailed data on seawater chemistry (especially PCO2 and aragonite
saturation state) for Willapa Bay, Washington where Pacific oysters have been the mainstayof the oyster aquaculture industry for almost 100 years and there is a long term record of
spawning and setting. They reconstruct this record for a longer historical period and their datasuggest that recent conditions provide a smaller window of optimal conditions (low aragonite
saturation state and warm enough temperatures for oyster spawning) than occurred
historically. While they did not sample larvae (see Ruesink et al 2017 below) and therefore
can’t confirm effects, they substantiate the complexity of measuring these effects andattributing them to a single cause in a variable estuary.

26

Ruesink, J.L., A. Sarich, and A.C. Trimble. 2017 Similar oyster reproduction across estuarine
regions differing in carbonate chemistry. ICES Journal of Marine Science,(DOI10.93/icesjms/fsx150).
These authors measured seawater chemistry in Willapa Bay, Washington, but unlike Hales etal (2017), they also present simultaneously collected data on four cohorts of Pacific oyster
larvae that were collected over three summers. The southern end of Willapa Bay has twoarms which create distinctly different characteristics because one is much more affected byriverine conditions that cause reduced aragonite saturation relative to the other. Oyster
settlement differed greatly between cohorts, but they did not find differences they could
attribute to this different water chemistry and instead found thermal conditions were perhaps
more important.
Ruesink, J.L., S. Yang, and A.C. Trimble. 2015. Variability in carbon availability andeelgrass (Zostera marina) biometrics along an estuarine gradient in Willapa Bay, WA, USA.
Estuaries and Coasts, 38: 1908-1917.
These authors collected data on eelgrass (Z. marina) and seawater chemistry along anestuarine gradient in Willapa Bay, Washington. They demonstrated that while eelgrass
responded to carbonate chemistry (increased tissue carbon up estuary where PCO2 increased
due to freshwater input), eelgrass production was unchanged and instead responded more to a
gradient with more organic rich sediments at this end.
13. Offshore mussel aquaculture: strategies for farming in the changing environment of
the U.S. EEZ in the Northeast U.S. Shelf
Darien Danielle Mizuta1*,2, Gary H. Wikfors1, Mark Dixon1, Edward J Maney Jr3
1
Northeast Fisheries Science Center, NOAA 212 Rogers Ave, Milford, Connecticut 06460
USA, *Email: darien.mizuta at noaa.gov
2
National Academy of Sciences, 2101 Constitution Ave NW, Washington, DC 20418 USA
3
Cat Cove Marine Lab, Salem State University, 352 Lafayette Street Salem, MA 01970
Abstract
The United States recently has become the largest importer of seafood in the world,
overcoming the past leader Japan, because of the nation’s limited domestic production. To
satisfy the increasing national demand for fisheries products, domestic aquaculture is to be
expanded. Challenges to U.S. aquaculture expansion, especially in the NE, include water
warming and salinity change trends [1], as well as other possible climate associated changes,
namely declining primary production, altered time of spawning, harmful algal blooms, andspecies physiological responses to these ecosystem changes [2]. As mariculture progresses
offshore to the U.S. Exclusive Economic Zone (EEZ), new issues need to be overcome, suchas the choice of appropriate practices for the high-energy environment and suitable species thatfavor production and minimize undesired environmental consequences. The blue mussel,
Mytilus edulis, is a promising candidate for offshore aquaculture because it requires no feeds,
assimilating in situ primary production and promoting nutrient bioextraction. Offshore mussel
farming, however, has many constraints including the selection of ecologically favorable sites
and seed availability and quality. To determine suitable sites and depth submersion of mussel
ropes in the water column for submersed long-line mussel farming, NOAA’s open source
climatologies and remote sensing data of temperature and chlorophyll a from 2005 to 2012were used to construct a “habitat suitability” analysis of southern New England EEZ areas.
Special importance was given to temperature, which affects mussel feeding, triggers

27

reproduction, and indirectly affects byssus effectiveness to adhere to farming ropes [3].
Considering ecological factors at present and anticipating temperature increases, our results
suggest mussel ropes be submerged during summer at a minimum of 15 m depth in northernand 20 m depth in southern areas of New England, where temperature is between 10-14°C andphytoplankton biomass abundant. Promising areas are where the thermocline is shallow suchas offshore Long Island, Cape Ann, and offshore New Hampshire, although mussels can beplaced deeper in water column in other locations during warmer months. Suitability of selectedsites will be validated by assessing water quality and the performance of mussels in situ with awell-developed flow-through device [4]. The biodeposition measurements also will allow
estimation of feeding patterns and feces and pseudofeces production that may have potential
local effects. A future step is to estimate the availability (sufficient quantity), quality (mortality,
free of diseases), and timing of spat offshore, as nearshore larvae are dispersed offshore bycurrents. These larvae have no chance to encounter a place to settle and currently can beconsidered “lost at sea”, i.e., unable to contribute to natural recruitment of mussels. Mussel
spat collectors will be deployed at trial farms at pre-defined seasons. Larval collection offshore
will satisfy legal requirements of “locally collected” seeds using larvae that would otherwise
be lost. The present project should ideally be conducted frequently to check for future
ecological variations. Based upon comparisons of historical and modern data, this research willcontribute to advancing American offshore shellfish aquaculture in the face of changing local
oceanographic characteristics and aquaculture industry needs.
Annotated Bibliography of Key Works[1] Fratantoni, P., T. Holzwarth-Davis, M.T. Taylor, 2017. Description of oceanographic
conditions in the Northeast US continental shelf during 2015. Northeast Fisheries Science
Center Reference Document 17-08.
The authors report on the hydrographic observations over different areas of the Atlantic
Northeast Shelf: western Gulf of Maine, Georges Bank, and Middle Atlantic Bight. Not only
averaged data but also anomalies were calculated, thus accounting for the variability that is
not related to seasonality. Waters where found to be more saline and 0.4 – 1.7°C warmer inthe samplings of the year 2015, with the highest anomalies in the Middle Atlantic Bight
during spring and summer. This work summarizes the findings of the 2015 samplings andgives a general overview of oceanographic trends in the area.
[2] E.H. Allison, M.C. Badjeck, K. Meinhold. 2011. The implications of global climatechange for molluscan aquaculture. In: Shumway, S.E. (Ed.) Shellfish Aquaculture and theEnvironment. Pp 461-490.
The authors of this paper instead of developing models predicting possible climate changes,
discuss the impacts of the climate to shellfish aquaculture and market based on an extensive
review of different relevant chemical and physical elements affecting the oceans. Authors
also suggest mitigation and management plans that can be applied for the sustainability of theshellfish farming.
[3] Lachance, A.A., B. Myrand, R. Tremblay, V. Koutitonsky, E. Carrignton. 2008. Biotic
and abiotic factors influencing attachment strength of blue mussels Mytilus edulis insuspended culture. Aquatic Biology, 2: 119-129.
In this paper, the authors describe a decrease in tenacity of mussel byssus during summer
spawning season and a negative relationship between high water temperatures and byssus
attachment strength, which affects the ability of mussels to support themselves on farming
ropes. The results of this study have strong implications for the suspended mussel culture
because with the warming water trends it is likely that mussels will begin to suffer more to
support attachment compared to those in the past.

28[4] Galimany, E., J.M. Rose, M.S. Dixon, G.W. Wikfors. 2013. Quantifying feeding behaviorof ribbed mussels (Geukensia demissa) in two urban sites (Long Island Sound, USA) withdifferent seston characteristics. Estuaries and Coasts, 36: 1265-1273.
The authors used for the first time in the USA an in situ flow-through equipment that allows
for quantification of all the important filtration and feeding parameters of a bivalve and foundout that ribbed and blue mussels have a strong plasticity, adapting their feeding strategies(filtration rate, gut transit rate, feces and pseudofeces production) according to thecharacteristics of the environment, such as organic and inorganic particulate concentrations.
Those results can be used for calculation of contribution of bivalves as potential cleaners ofautotrophic environments through bioextraction.
14. Nutrient environment in Gokasho Bay, effects of fish aquaculture on inorganic
nutrient levels
Satoshi Watanabe1*, Masayuki Minakawa2, Yuka Ishihi1, Natsuki Hasegawa1 and Toshie
Matsumoto1
1

National Research Institute of Aquaculture, Japan Fisheries Research and Education
Agency, 422-1 Nakatsuhamaura, Minamiise, Mie, 516-0193, Japan, *E-mail: swat ataffrc.go.jp
2
National Research Institute of Aquaculture, Japan Fisheries Research and Education
Agency, 224-1 Hiruda, Tamaki, Mie, 519-0423, Japan
Abstract
With the global expansion of aquaculture production, eutrophication derived from aquaculture
effluent and consequent environmental deterioration are becoming increasingly problematic inmany parts of the world. On the other hand, eutrophication has been reduced in coastal watersof Japan as a result of mitigation efforts over the past thirty years. While such efforts havepositive effects on maintaining environmental integrity, excessive reduction of nutrient load tothe coastal environment is thought to have reduced the productivity of many fishery resources
and unfed aquaculture in Japan. Our hypothesis is that putting aquaculture effluent into
practical use enhances the production of coastal fishery and unfed aquaculture. This
presentation is a partial report of the long-term periodical monitoring of water quality in
Gokasho Bay, Mie, Japan. To acquire basic information on the influential extent of aquaculture
effluent on carrying capacity of coastal waters, environmental surveys have been conducted toinvestigate the behaviour of nutrients and primary production covering the whole bay area andalso more intensively around the red seabream, Pagrus major, aquaculture cages. Seawater
samples have been collected monthly at 3 depths (surface, mid-layer and bottom) at 19 points
in the bay, and seasonally at surface and depth of 5 m (i.e. midpoint of the cage depth) at 47
points approximately 20 m apart from one another around the red seabream aquaculture cages
since November 2016. The concentration of the following nutrients has been analyzed:
dissolved inorganic nitrogen (DIN: NH4+-N, NO2--N, NO3--N), PO43- and SiO2 with an autoanalyzer (TRAACS 800, Bran+Luebbe). A CTD (RINKO profiler, JFE Advantech) has beenused to obtain the vertical profile of temperature, salinity, dissolved oxygen (DO), andchlorophyll a at depths of every 10 cm from the surface to the bottom. Although the DIN-N
and DO levels in December 2016 were comparable to those from the same month in 1980s
where aquaculture was more prosperous, the PO4-P level was an order of magnitude lower
probably due to diminished aquaculture production and improved feeding management
including the switch from raw bait to formulated feed. During a diatom bloom observed in29

November 2016, the depletion of SiO2 implied that the availability of Si, but not N or P, seemed
to be the limiting factor for the diatom growth in Gokasho Bay. There were spots with a higher
NH4-N level at the center and 20 m outside the red seabream cage area in January 2017. The
chlorophyll a level was higher and NO3-N was lower around the cages than in the surrounding
water. The observed lower NO3-N concentration may indicate that the enhanced primary
production triggered by the NH4-N supply from the aquaculture effluent rapidly consumed not
only NH4-N but the background NO3-N in the area. If this is true, DIN-N excreted from red
seabream may not travel far from the cages to fertilize seaweed aquaculture, and the seaweedshould be cultured in the vicinity of the cages. The elevation of chlorophyll a indicates thepossibility of productive co-culture of red seabream and bivalves.
Annotated Bibliography of Key Works
Yamamoto, T. 1992. Constant uptake of ammonium-N and nitrate-N by Porphyra yezoensis
thalli. J. Fac. Appl. Bio. Sci. Hiroshima Univ. 31: 155–159.
The author experimentally determined the uptake rates of ammonium-N and nitrate-N byPorphyra (currently Pyropia) yezoensis using 15N as a tracer. Pyropia yezoensis (laver ornori) is an important seaweed in Japan. Specific uptake rate of ammonium-N (0.0017/hr) was
more than 8 times higher than that of nitrate-N (0.0002/hr). The uptake rates were constantover the 120-minute experiment, unlike in the case of phytoplankton that is known to rapidly
absorb nutrients to satiation. Fertilizers with ammonium-N as the main component may besuitable for nori aquaculture. The nitrogenous fertilizer should be provided to nori at a low
concentration over a long duration to avoid induction of phytoplankton bloom.
Kakehi, S., Fujiwara, T and Yamada, H. 2005. Seasonal variation in the nutrient standing
mass and nutrient budget of Ise Bay. Umino Kenkyu (Oceanography in Japan) 14: 527-540.
The authors estimated the standing mass of dissolved inorganic nitrogen (DIN) and dissolved
organic phosphorus (DIP) by the linear regression of apparent oxygen utilization (AOU) or
the interpolation of the surface and bottom nutrient concentrations to elucidate the seasonalvariations in Ise Bay, Japan. The DIN standing mass in the bottom layer ranged from 1500 to
2600 t, tending to be higher in summer than in winter. The DIN was smaller in the surface
layer than in bottom layer in summer, and comparable between the two layers in winter. The
DIP standing mass showed more distinct seasonal trend. It was 200 t in surface and bottom
layer in winter; whereas it increased to 400 t in the surface and 800 t in the bottom later insummer. The temporal change of the standing mass of the nutrients was more dependent
upon biological and chemical processes than physical processes such as seawater exchange.
Chlorophyll level is inversely related with DIN and DIP in the surface layer in summer, but
DIN and DIP are not completely synchronous. The DIP seemed to be released from the sea
sediment in summer where hypoxic water is formed in the bottom layer. Denitrification
seemed to take place year-roun
15. Challenges and opportunities of IMTA in Hawaii and beyond
Cheng Sheng Lee
Center for Tropical and Subtropical Aquaculture, Oceanic Institute, 41-202 Kalanianaole
Hwy., Waimanalo, HI 96795, USA, Email: cslee at hpu.edu
Abstract
Available consumable seafood for 7.3 billion population in 2014 was 20 kg per capita (FAO
2016). To maintain the same level of seafood supply for expected 9.7 billion population in
2050, the total world seafood supply requires additional 48 million metric tonnes. With the30stagnant yield from capture fisheries, the increase has to come from aquaculture. Although theannual growth of aquaculture production has slowed down, theoretically aquaculture
production will reach the targeted production level. However, current intensive monoaquaculture practices have faced the challenges of sustainability and must change its operation
to meet the criteria of sustainable development defined and adopted by UN’s 193 Member in2015. UN members adopted the 2030 Agenda for Sustainable Development and call for an
integrated approach that addresses all three dimensions of sustainable development (economic,
social and environmental). Current aquaculture practices consume nature resources andcompete with each other. Ecosystem based aquaculture management is essential to co-exist
with other social activities and to efficiently utilize natural resources for food production andconservation of nature stocks. Integrated multi-trophic aquaculture (IMTA), an old concept
with new knowledge, appears to be the answer to sustainable development in aquaculture.
IMTA practice combines the cultivation of fed aquaculture species, and extractive aquaculture
species (both organic and inorganic ones) to reduce wastes and to create balanced eco-systems.
Additionally, IMTA can play important roles in disease control and management, climatechange mitigation, and others. As a result, IMTA has received more and more attentions at theturn of the century. However, the feasibility of IMTA comparing to mono-culture has yet to be
documented. This presentation discusses the sustainability of IMTA by reviewing the practiceof IMTA concept in traditional Hawaii aquaculture back to 1000 A.D. to current practices in
the U.S. and beyond; updates US-Korea bilateral IMTA project; and challenges of IMTA.
Annotated Bibliography of Key Works
Sato, V. T. and C.-S. Lee. 2007. Keeper of Molii Pond. Oceanic Institute. 148 pp.
An oral history of a man, George Uyemura who spent 70 years of his life at Molii Pond was
documented at this book to share his knowledge and experience in managing the fish pond.
This book offers a look at the history and methodology of sustainable management of
Hawaiian fishponds. It is a start reference book to know more about Hawaiian fishpond.
Soto, Doris (ed.) 2009. Integrated mariculture- A global review. FAO Fisheries andAquaculture Technical Paper 529. 184 pp.
This report contains three desk studies encompassing global views of practices and future
prospects for integrated aquaculture in coastal and marine areas in three climatic zones:
temperate, tropical and Mediterranean Sea as a special Mediterranean enclosed ecosystem.
The commissioned review papers describing integrated aquaculture in coastal and marine
environments were technically supervised by Mrs. Doris Soto, Senior Fisheries Officer(FIMA). The activity and the publication have been partly funded through a Japanese TrustFund Project (Towards Sustainable Aquaculture: Selected Issues and Guidelines). It is agood reference report to get start to know about integrated mariculture.
Thomas, Susan A. (ed.) 2011. Integrated Multi-Trophic aquaculture: A Workshop” at
Peninsula College Port Angeles, Washington. Bull. Aquacul. Assoc. Canada 109-2, 13 pp.
https://www.researchgate.net/publication/257819653
This report summarized the first US-based workshop on integrated multi-trophic aquaculture(IMTA). The two days’ workshop included presentation and breakout sessions to conduct“strengths-weaknesses-opportunities-threats” (SWOT) analysis for ecological, economic, andsocial impacts of IMTA. It concluded IMTA could help to move the US toward becoming amajor aquaculture producer in the world, because it might resolve some of the issues thatseem to be limiting such progress. This is a good reference base for any further SWOT
analysis.

31

Bellona 2013. Traditional and Integrated Aquaculture. Bellona report 2013, 114 pp.
www.bellona.org
Bellona has been involved in the hunt for new solutions, new resources and new products thatwill be important for the future. This report points out that salmonid industry has highambitions for growth, but it must happen in harmony with the ecosystem. It explains why
aquaculture should progress from salmonid monoculture to integrated and sustainableecosystems and how. Also, this progress depends on the aquaculture industry, research
institutions and politicians working together. It is a good lesson for other aquaculture industry
to learn from a mature salmonid industry to think ahead.
Gunning, D., J. Maguire and G. Burnell. 2016. The development of sustainable saltwaterbased food production systems: a review of established and novel concepts. Water, vol. 8,598. 37pp.
This review article examines the potential negative impacts of saltwater mono-aquaculture
operations and how the novel approach such as IMTA, constructed wetlands and saltwateraquaponics will mitigate the negative impacts.

Poster Presentations

Possible effects of terrestrial managements on seagrass ecosystem functionings
Christopher Bayne*, Hideki Hamaoka and Masakazu Hori
National Research Institute of Fisheries and Environment of Inland Sea, Fisheries Research
Agency, Japan, *Email: bayne at affrc.go.jp
Abstract
Seagrass species function as typical foundation species which support high productivity anddiversity because of their high rates of primary production and their ability to provide
associated organisms with trophic support, refuge from predation, and spawning substrates.
Seagrass associated species, especially herbivorous invertebrates, can regulate the ecosystem
functioning of seagrass beds, suggesting that this interaction is an important key to clarify the
relationship between biodiversity and ecosystem functioning in coastal ecosystems. Seagrass
communities are characterized by wide occurrence in shallow nearshore areas, where there isa boundary between terrestrial and marine ecosystems. Therefore, seagrass communities areoften influenced by various factors derived from terrestrial habitats, such as agrichemicals andnutrients through fresh water input. Although terrestrial nutrients are essential for productivity
for nearshore marine plants including seagrass species, increased nutrients cause
eutrophication and phytoplankton blooming resulting in the degradation of seagrass growthand distribution. Agrichemicals from river, adjacent agriculture fields and forests also haveserious effects on seagrass communities; in particular insecticide has caused mass mortality ofthe seagrass-associated invertebrates, resulting in vulnerable ecosystem functioning of seagrassbeds. The inflow of both agrichemical and nutrients into nearshore areas has increased with thechange of the adjacent terrestrial management. In this study, we demonstrated interactive effectof insecticide with eutrophication on ecosystem functioning of seagrass beds using
manipulative experiments in Seto Inland Sea, Japan. In the manipulation, we used theinsecticide carbaryl to exclude invertebrate herbivores and the fertilizer to add nutrients, which32

is a technique developed by the Zostera Experimental Network (ZEN), a global collaborative
network of scientists studying the structure and functioning of ecosystems supported byeelgrass. The technique enables us especially to demonstrate the indirect effect of epiphyte
grazing by the associated invertebrates on eelgrass growth (e.g., Whalen et al. 2013). The
carbaryl loading significantly decreased the density and diversity of herbivorous invertebrates
and indirectly increased epiphyte biomass, resulting in a significant difference in seagrass
growth, although carbaryl concentrations were within the safety standards even at theexperiment site. However, the nutrient addition significantly changed the indirect effect ofcarbaryl loading on seagrass growth. These results suggest that seagrass-associated herbivores
can regulate ecosystem functioning of seagrass beds, and indicate the possibility that both
agrichemical and nutrient loading can easily change the seagrass ecosystem functionings evenin lower concentration. Both agrichemical and nutrient loading from terrestrial habitat tonearshore areas would be easy to change and vary spatially with land use change, so that weshould pay attention to the management for the adjacent terrestrial habitats.
Annotated Bibliography of Key Works
Duffy, J., P. Reynolds, C. Boström, J. Coyer, M. Cusson, S. Donadi, and S. Fredriksen. 2015.
Biodiversity mediates top–down control in eelgrass ecosystems: a global comparative‐
experimental approach. Ecology letters, 18(7): 696-705.
This paper investigates top-down and bottom-up effects of adding nutrient and deterrents toeelgrass (Zostera marina) beds at 15 sites across the range of this species. They found thatremoving grazers had a stronger average effect on epiphytic biomass than local addition ofnutrients, revealing stronger top-down control by grazers. Also, they found that the influencesof biodiversity in their global analysis are very similar to results from other small-scale
experiments. These include sites with more genotypically diverse eelgrass with higher
crustacean biomass and lower algal biomass at sites with increased grazer species.
Reynolds, P., J. Stachowicz, K. Hovel, C. Boström, K. Boyer, M. Cusson, and J. Duffy. 2017.
Biogeography of predation pressure in eelgrass across the Northern Hemisphere.
Unpublished manuscript. Virginia Institute of Marine Science, Virginia USA.
Studies across broad geographic ranges exploring drivers of change in predator interactions
are relatively rare. The authors surveyed predation on a common amphipod prey in eelgrass(Zostera marina) beds at 42 sites across the Northern Hemisphere. At all coasts, predation
declined with latitude, but declined more in areas where temperature gradients are steeper.
Whalen, M., J. Duffy, and J. Grace. 2013. Temporal shifts in top-down vs. bottom-up controlof epiphytic algae in a seagrass ecosystem. Ecology 94: 510-520.
The authors used a cage-free approach of manipulating mesograzer abundance and epiphyticloading over a temporal period, by using deterrent and nutrient treatments. They found that
reduction of mesograzer abundance and increase in nutrients can allow increased epiphytic
algae growth on eelgrass (Zostera marina). By performing the experiment in the fall andsummer, they found that the dominant factors that controlled epiphytic algae abundancechanged. In fall, there was a natural decrease in mesograzer abundance, and by adding
nutrients, which caused bottom-up factors to dominate, increased epiphyte biomass. In
summer, added deterrents, stimulating strong top-down factors, decreased mesograzer
abundance and caused an increase in epiphyte biomass. Also, unexpectedly, they found thatdrift macroalgae indirectly reduced epiphytes by proving structure for mesograzers.

Genetic effects of the tiger puffer stock enhancement program on wild population in thesea around Japan

33

Daisuke Katamachi
National Research Institute of Fisheries and Environment of Inland Sea, Hatsukaichi,
Hiroshima 739-0452, Japan, Email: kata79 at fra.affrc.go.jp
Abstract
Since 1977, millions of hatchery-reared tiger puffer, Takifugu rubripes, juveniles have beenreleased for stock enhancement in the sea around Japan. The stock enhancement program has
contributed to catches, however, no information about genetic effects of the program on wild
population is available. The genetic effects were evaluated with highly polymorphic DNA
marker sets (1962 bp mitochondrial DNA sequences and 11 microsatellite DNA loci) using
316 mature wild adults from nine identified or possible spawning sites in the sea around Japan,
276 wild juveniles in the Ariake Sea which is a possible spawning site and an identified nursery,
85 hatchery-reared juveniles, 150 mature hatchery-released adults in the Ariake Sea. Both typesof markers indicated that hatchery-reared and hatchery-released populations had lower genetic
variability than wild populations, however, hatchery-released population had closer genetic
variability to wild populations. Microsatellite FST estimates indicated hatchery-reared andhatchery-released populations were significantly different from wild populations. On the other
hand, significant differences were observed only between hatchery-reared population and wild
populations with mitochondrial ΦST estimates. Microsatellite FST estimates and Bayesianclustering analysis revealed population structure of the tiger puffer, however, the population
structure was not associated with the history and scale of stock enhancement program. The
genetic variability was almost equivalent among wild populations, no significant deviationfrom Hardy-Weinberg equilibrium and significant linkage disequilibrium were detected fromwild populations. Moreover, putative wild juveniles having a high possibility of being related
to mature hatchery-released adults were detected based on relatedness among individuals in
the Ariake Sea. These results suggested that there is a high possibility that hatchery-releasedfish breed in the wild, however, negative genetic effects of the stock enhancement program on
wild populations were not likely in the tiger puffer. As one of the factors, it is considered thatmature hatchery-released population is composed of multiple groups and year classes and haveclose genetic characteristics to wild populations.
Annotated Bibliography of Key Works
Araki H., B. Cooper, MS. Blouin. 2007. Genetic effects of captive breeding cause a rapid,
cumulative fitness decline in the wild. Science, 318: 100-103.
Captive breeding is used to supplement populations of many species that are declining in thewild. The suitability of and long-term species survival from such programs remain largely
untested, however. We measured lifetime reproductive success of the first two generations ofsteelhead trout that were reared in captivity and bred in the wild after they were released. By
reconstructing a three-generation pedigree with microsatellite markers, we show that genetic
effects of domestication reduce subsequent reproductive capabilities by ~40% per captivereared generation when fish are moved to natural environments. These results suggest thateven a few generations of domestication may have negative effects on natural reproduction in
the wild and that the repeated use of captive-reared parents to supplement wild populations
should be carefully reconsidered.
Hamasaki K., S. Toriya, H. Shishidou, T. Sugaya, S. Kitada. 2010. Genetic effects ofhatchery fish on wild populations in red sea bream Pagrus major (Perciformes, Sparidae)
inferred from a partial sequence of mitochondrial DNA. Journal of fish biology, 99: 21232136.

34

Variation in the mitochondrial DNA transcriptional control region sequence was investigatedin wild and hatchery-released red sea bream Pagrus major from Kagoshima Bay, where an
extensive hatchery-release programme has been conducted for >30 years. The programme
has successfully augmented commercial catches in the bay (released juveniles have been
produced from the captive broodstock, repeatedly used over multiple generations). Samples
were also obtained from outside the bay, where limited stocking has occurred. Genetic
diversity indices measured as number of haplotypes, haplotype richness, haplotype diversity
and nucleotide diversity were lower in hatchery-released fish than in wild fish. Genetic
differences in wild fish from the bay, especially in the inner bay, compared with fish fromoutside the bay were detected in terms of decreased genetic diversity indices and changed
haplotype frequencies. Unbiased population pair-wise FST estimates based on an empirical
Bayesian method, however, revealed low genetic differentiation between samples from thebay and its vicinity. Mixed stock identification analyses estimated the proportion of hatcheryreleased fish in wild populations in the inner and central bays at 39·0 and 8·7%, respectively,
although the precision of the estimates was very low because of the small genetic
differentiation between populations and relatively small sample sizes. Hence, the long-term
extensive hatchery release programme has affected the genetic diversity of wild populationsin the bay; however, the genetic effects were low and appeared to remain within the bay.
Blanco Gonzalez E., M. Aritaki, S. Sakurai, N. Taniguchi. 2013. Inference of potential
genetic risks associated with large-scale releases of red sea bream in Kanagawa prefecture,
Japan based on nuclear and mitochondrial DNA analysis. Marine biotechnology, 15: 206220.
Since 1978, millions of hatchery-reared red sea bream (Pagrus major) juveniles have beenreleased in Sagami Bay and Tokyo Bay in Kanagawa Prefecture, Japan. The stockenhancement program has contributed to total catch; however, no information regarding thegenetic interactions with wild counterparts is available. Here, we combined 15 microsatellite
loci and mitochondrial D-loop sequencing to characterize the genetic resources of red sea
bream in Sagami Bay and Tokyo Bay and to elucidate the potential harmful genetic effects
associated with fish releases. Both types of markers evidenced higher levels of genetic
diversity in wild samples (SB and TB) compared with offspring before stocking (H07 andH08) as well as a hatchery-released sample recaptured in Sagami Bay (HR). Microsatellite
FST estimates and Bayesian clustering analysis found significant genetic differences among
samples (FST = 0.013-0.054), except for the two wild samples (FST = 0.002) and HR vs. H07(FST = 0.007). On the other hand, mitochondrial-based ФST suggested haplotypic similarity
between SB, H07, and HR. The low effective number of females contributing to the offspringover multiple generations may be responsible for the lack of haplotypic differentiation.
Moreover, the putative hatchery origin to three fish (8 %) without deformity in the internostril epidermis was inferred for the first time. Our results showed the usefulness of
combining nuclear and mitochondrial markers to elucidate genetic interactions between
hatchery-released and wild red sea bream and warned about potential harmful genetic effects
should interbreeding takes place.
Nakajima K., S. Kitada, Y. Habara, S. Sano, E. Yokoyama, T. Sugaya, A. Iwamoto, H.
Kishino, K. Hamasaki. 2014. Genetic effects of marine stock enhancement: a case study
based on the highly piscivorous Japanese Spanish mackerel. Canadian Journal of Fisheries
and Aquatic Science, 71: 301-314.
We used a before–after control–impact design to quantify the genetic effects of the large
piscivorous Japanese Spanish mackerel (Scomberomorus niphonius) stock enhancement
program on wild populations in the Seto Inland Sea. Samples of 1424 wild and 230 hatcheryfish collected from 13 sites around Japan were genotyped using five microsatellite markers.

35

A total of 758 wild and 103 hatchery fish were sequenced for the mitochondrial DNA D-loop
region. The population structure of Japanese Spanish mackerel was panmictic around Japan.
Hatchery fish had significantly lower genetic diversity indices than did wild fish. However,there was no significant change in any of the diversity indices in the Seto Inland Sea, despite
the substantial genetic mixing proportion of hatchery-origin genes (7.8%–14.5% fromreleases in 2001 and 2002), a conclusion supported by simulations. The estimated effective
population size was surprisingly small (~430–970) but stable in the Seto Inland Sea
compared with the large census size. A Ryman–Laikre effect was not likely in the Japanese
Spanish mackerel.
Assessment of the ichthyotoxicity of harmful marine microalgae Karenia spp. using
cultured gill cells from red sea bream (Pagrus major)
Nobuyuki Ohkubo1*, Yuji Tomaru1, Haruo Yamaguchi2, Setsuko Sakamoto1, Kazuhiko
Mochida1
1

National Research Institute of Fisheries and Environment of Inland Sea, Japan Fisheries
Research and Education Agency, 2-17-5 Maruishi, Hatsukaichi, Hiroshima 739-0452,
Japan, *E-mail: nobuyuki at affrc.go.jp
2
Faculty of Agriculture, Kochi University, Nankoku, Kochi 783-8502, Japan
Abstract
The present study reports the development of a method to investigate ichthyotoxicity ofharmful marine microalgae using cultured red sea bream (Pagrus major) gill cells. The cultured
gill cells formed adherent 1–2 layers on the bottom of the culture plate, and could tolerateseawater exposure for 4 h without significant alteration in cell survival. The microalgae
Karenia mikimotoi, Karenia. papilionacea, K. papilionacea phylotype-I, Karenia digitate andHeterosigma akashiwo were cultured, then directly exposed to gill cells. Live gill cell coverageafter K. mikimotoi, K. papilionacea phylotype-I, and K. digitate exposure were significantly
lower than in the cells exposed to a seawater-based medium SWM-3 and IMK (control cells;
P < 0.05). Toxicity of K. mikimotoi cells was weakened when the cells were ruptured, and was
almost inexistent when the algal cells were removed from the culture by filtration. Significant
cytotoxicity was detected in the concentrated ruptured cells, although cytotoxicity was
weakened in the concentrated of ruptured cells after freezing and thawing; whereas,cytotoxicity almost disappeared after heat treatment. In addition, examination of the
distribution of toxic substances from the ruptured cells showed that cytotoxicity mainly
occurred in the fraction with the resuspended pellet after centrifugation at 3000 × g.

Asari clam predation by intertidal fishes: feeding habits of immature black porgy,
Acanthopagrus schlegelii in Yamaguchi Bay, western Seto Inland Sea, Japan
Toshihiro Shigeta1*, Mutsumi Tsujino1, Takeshi Tomiyama2, Yoichi Sakai2 and Hidetoshi
Saito2
1

National Research Institute of Fisheries and Environment of Inland Sea, Japan Fisheries
Research and Education Agency, Hatsukaichi, Hiroshima 739-0452, Japan, *Email: shigeta
at fra.affrc.go.jp
2
Graduate School of Biosphere Science, Hiroshima University, Higashi-Hiroshima,
Hiroshima 739-8528, Japan36

Abstract
Black porgy, Acanthopagrus schlegelii (Family: Sparidae), is a commercially important fish in
Japan. In 2015, commercial catches of the porgy in Japan and the Seto Inland Sea of westernJapan were 3,181 metric tons and 1,508 metric tons, respectively. This species is known as amajor predator of Asari clam, Ruditapes philippinarum in tidal flats. On the other hand, Asariclam is a commercially important species, too. Recently, the clam catches have decreased inJapan. Especially in the Seto Inland Sea, the catches have remarkably dropped to 137 metrictons in 2015 from 45,023 metric tons in 1985 (peak level). Several reports concerning
protecting clam beds with netting suggest that predation is one of the most important factors
for the survival of the clam. In order to restore Asari clam resource, it is necessary to clarify
the habits of the porgy. In this study, we investigated the seasonal occurrence and feeding
habits of immature-sized porgy (less than about 25 cm total length) in tidal flats from 2005 to2017 in Yamaguchi Bay, western Seto Inland Sea. 102 individuals of the porgy (10.4-27.7 cm
TL) were collected by rod-and-line fishing there. The monthly catch per unit effort (CPUE:
number of fish caught/3 hours/person) of the porgy ranged 0-2.9. The CPUE rapidly increasedin June. In July, it reached 2.9, the highest annual value, after which the CPUE maintained highvalues from August to November. From December values were low (0-0.4) again. These results
indicate that immature A. schlegelii occurs seasonally in the tidal flats from June to November.
Bases on the stomach contents of the porgy, bivalves such as Asian mussel, Arcuatulasenhousia, Japanese razor clam, Solen strictus were the most important prey items in wet
weight. Next, Japanese mud shrimp, Upogebia major was the second important one. Thesebenthic animals were in common and are filter feeders on phytoplankton, benthic microalgae,
and detritus. Immature-sized porgy preyed on juvenile Asari clams ranging from 2.8 to 18.0mm shell length. The values of stable isotopes of δ13C and δ15N on black porgy showed -17.6-16.0‰ and 16.2-17.7‰, respectively. In the Seto Inland Sea of Japan, resources ofbenthotrophic fish species, such as flatfishes and pufferfishes, which use the estuary in theirearly life history, have decreased remarkably. For recovery and regeneration of these criticalresources, it is necessary to clarify the relationships between organisms and the estuarine
ecosystem.
Annotated Bibliography of Key Works
Shigeta T. and H. Usuki. 2012. Predation on the short-neck clam Ruditapes philippinarum byintertidal fishes: a list of fish predators. Journal of Fisheries Technology, 5(1): 1‒19. (inJapanese with English abstract)
Recently, commercial catches of the short-neck clam Ruditapes philippinarum havedecreased in Japan. Especially in the Seto Inland Sea, western Japan, the clam catches haveremarkably dropped. Several reports suggest that predation by fishes is one of the mostimportant factors for the survival of the clam. In this review, we made a list of fish species
that forage on the short-neck clam in the field. Twenty-three fishes ranging from
Myliobatidae to Tetraodontidae (12 families) are listed in the world. Among them, 21
intertidal fishes (12 families) occur in Japan. It was clarified that five fishes, the Longheaded
eagle ray Aetobatus flagellum, the Black porgy Acanthopagrus schlegelii, the Yellowfin
seabream A. latus, the Kyuusen wrasse Parajulis poecilepterus and the Grass puffer Takifugu
niphobles, foraged on whole adult-sized clam (>20 mm shell length). At least, the siphon was
cropped by eight fishes including the Stone flounder Kareius bicoloratus, the Marbled sole
Pseudopleuronectes yokohamae, and the Japanese sillago Sillago japonica. Meanwhile, theBlack porgy and the Kyuusen wrasse preyed on all parts except the foot of the clam. We arecontinuing to analyze details of the interaction between these intertidal fishes and the shortneck clam.

37

Evaluation of inexpensive Raspberry Pi-based time-lapse camera system for tidal flatecosystem observation
Naoaki Tezuka1* and Kazumasa Oguri2
1

National Research Institute of Fisheries and Environment of Inland Sea, Maruishi,
Hatsukaichi, Hiroshima 739-0452, Japan, *Email: tezukan9 at affrc.go.jp
2
Japan Agency for Marine-Earth Science and Technology, Natsushima, Yokosuka,
Kanagawa 237-0061, Japan
Abstract
In recent years, changes in the structure of coastal ecosystems, leading to a collapse of
conventional fisheries, have been widely reported. Maintaining clam fisheries or aquaculture
production in general has becoming increasingly difficult without adequate predator prevention
measure, especially in the tidal flats of western Japan, indicating certain changes in the
structure of the ecosystem. It is suggested that migratory fish species influence the benthic
community structure through predation in the tidal flat ecosystem. However, inadequate
information exists on the abundance or frequency of the appearance of migratory fish species
in tidal flats; hence, its impacts on the benthic community are unclear. Observation using an
underwater time-lapse camera system can be an effective approach to understanding the
temporal change in the abundance of migratory fish species in tidal flats and their influence on
the ecosystem. We have, therefore, developed and tested an inexpensive Raspberry Pi-based
underwater time-lapse camera system to observe the tidal flat ecosystem processes. The
Raspberry Pi is an inexpensive single-board computer that can be connected to a dedicatedcamera module. Our system consists of Raspberry Pi with a camera module, USB battery, timelapse power control unit, and optional light emitting diode (LED) module and temperature
sensor. The camera system uses the command line interface for operation setting, i.e., setting
the initial wakeup time, repeat times, and the interval. It takes still and/or video images after
wakeup, and then shuts down until the next scheduled wake-up time. We placed the entire
system, excluding the LED module and temperature sensor, in an inexpensive underwater
housing structure made with polyvinyl chloride (PVC) water pipe sockets and an acrylic
window. The camera system successfully captured underwater time-lapse images duringobservations, except under low visibility conditions, or when biofouling occurs. However,certain improvements are required, which include improving the image quality under low-light
conditions by increasing the brightness of the light module, widening the field of view of theimage, and adding an anti-biofouling mechanism.

Development of Free-Ocean Real-Time Experimental System (FORTES) for in-situ CO2
manipulation in eelgrass beds
Tatsuki Tokoro1*,2, Masakazu Hori1, Tomohiro Kuwae2, Yuichi Isaka3, Hyojin Ahn3 andMasahiro Nakaoka3
1

National Research Institute of Fisheries and Environment of Inland Sea, Maruishi,
Hatsukaichi, Hiroshima 739-0452, Japan, *Email: ttokoro at affrc.go.jp
2
Port and Airport Research Institute, Nagase, Yokosuka, Kanagawa 239-0826, Japan3
Akkeshi Marine Station, Hokkaido University, Akkeshi, Hokkaido 088-1113, Japan
Abstract

38

Ocean acidification (OA) causes various effect on coastal resources. For eelgrass beds, positive
and negative effects are expected on different functional groups of biological communities. In
addition, the acidification level in coastal ecosystems vary greatly due to the CO2 consumption
and production by marine plants and input of freshwater. To understand the actual influencesof OA under such complicated conditions, in-situ field experiments for manipulating CO2 arepromising. FOCEs (Free ocean carbon experiments, Gattuso et al., 2014) have already been
established in several marine habitats such as coral reefs and Posidonia seagrass beds. However,these systems have several problems such as changing in-site hydrodynamic conditions, theneeds to electrical power to operate the system, and high installation cost. To overcome suchdifficulties, we have developed a newly CO2 manipulating system on the site, named FORTES(Free-Ocean Real-Time Experimental System). The system allows control of the acidificationlevel in the area of square meters of eelgrass beds by supplying a high concentration of CO2dissolved water under mostly opened condition. No electrical power is required because thissystem could be operated by the pressure and buoyancy of injected CO2. The CO2-dissolved
water is always emitted to the experimental area from the upstream direction even when thecurrent direction changes with tide and other factors. In the test trials of FORTES in eelgrassbeds in Oki Island and Akkeshi lagoon in Japan, the acidification level expected in 2100 was
reproduced successfully. Furthermore, this system enables the supply of water-soluble
nutrients and the deterrent of invertebrate grazers along with the CO2 for simultaneous control
of nutrient levels and grazer densities. This orthogonal design allows the experiments to
examine interacting effects of ocean acidification and other factors in the eelgrass bed
community.
Annotated Bibliography of Key Works
Gattuso, J-P., W. Kirkwood, J.P. Barry, E. Cox, F. Gazeau, L. Hansson, I. Hendriks, D.I.
Kline, P. Mahacek, S. Martin, P. McElhany, E. T. Peltzer, J. Reeve, D. Roberts, V. Saderne,
K. Tait, S. Widdicombe, and P. G. Brewer. 2014. Free-ocean CO2 enrichment (FOCE)
systems: present status and future developments, Biogeosciences, 11: 4057–4075.
Free-ocean CO2 enrichment (FOCE) systems are designed to assess the impact of ocean
acidification on biological communities in situ for extended periods of time (weeks tomonths). They overcome some of the drawbacks of laboratory experiments and fieldobservations by enabling (1) precise control of CO2 enrichment by monitoring pH as anoffset of ambient pH, (2) consideration of indirect effects such as those mediated throughinterspecific relationships and food webs, and (3) relatively long experiments with intact
communities. Bringing perturbation experiments from the laboratory to the field is, however,extremely challenging. The main goal of this paper is to provide guidelines on the generaldesign, engineering, and sensor options required to conduct FOCE experiments. Another goal
is to introduce xFOCE, a community-led initiative to promote awareness, provide resources
for in situ perturbation experiments, and build a user community. Present and existing FOCE
systems are briefly described and examples of data collected presented. Future developments
are also addressed as it is anticipated that the next generation of FOCE systems will include,in addition to pH, options for oxygen and/or temperature control. FOCE systems should
become an important experimental approach for projecting the future response of marine
ecosystems to environmental change.

A comparison of environmental and biological parameters at asari, Ruditapes
philippinarum, fishing grounds in Japan for understanding the cause of recent
catastrophic decrease of asari clam39

Motoharu Uchida1*, Mutsumi Tsujino1, Naoaki Tezuka1, Toshihiro Shigeta1, Yoshitake
Takada2, Yuka Ishihi3, Satoshi Watanabe3, Shuhei Sawayama4, Hiroaki Kurogi4 and Kentaro
Niwa5
1

National Research Institute of Fisheries and Environment of Inland Sea, Hatsukaichi,
Hiroshima, 739-0452, Japan, *Email: uchida at affrc.go.jp
2
Japan Sea National Research Institute, Chuo-ku, Niigata 951-8121, Japan
3
National Research Institute of Aquaculture, Minamiise, Mie 516-0193, Japan
4
National Research Institute of Fisheries Science, Yokosuka Station, Nagai Yokosuka,
Kanagawa 238-0316, Japan
5
National Research Institute of Fisheries Science, Fukuura, Kanazawa, Yokohama,
Kanagawa 236-0003, Japan
Abstract
The catastrophic decrease of catch of the asari clam, Ruditapes philippinarum, has been
observed for the last three decades in Japan’s coastal waters. Many factors including
overfishing, disease, habitat loss, competition with invasive species, global warming, andaltered trophic cascade are suggested to be involved. However, major factor is still not wellcharacterized to explain the widespread and long-term decrease of the catch. We conductedcomprehensive comparison of environmental and biological characteristics among asari fishinggrounds in Japan. Significant relationship was observed between water nutrient level (i.e., total
nitrogen and chlorophyll a) and the asari catch. Stable carbon isotope ratio of asari was foundto be a useful indicator representing not only the nutrient level but also the asari catch per unit
area. Significant relationship was also observed between the benthos biomass (macrobenthos,
meiobentos, and nematodes) and the asari catch. All these observations suggest that recent
catastrophic biomass decrease is occurring not only for asari but also for wide range of benthic
organisms in Japan’s coastal waters.
This study was conducted by a research fund entitled a feasibility study on biodiversity
assessment methods in fishing ground environment from Fisheries Agency.