35th Scientific Symposium

UJNR Aquaculture Panel

November 13th-14th, 2006

Building Sustainable Food Supplies
through Aquaculture, Wild Stock Enhancement,
and Habitat Management
Program and Abstracts

National Research Institute of Aquaculture,
Fisheries Research Agency, Mie 516-0193, Japan-0-

35th Scientific Symposium

UJNR Aquaculture Panel

November 13th-14th, 2006
National Research Institute of Aquaculture,
Fisheries Research Agency, Mie 516-0193, Japan

Building Sustainable Food Supplies through Aquaculture,
Wild Stock Enhancement, and Habitat Management

Aim of the symposium:
The role of aquaculture in stabilizing food supplies has been globally important,while production based on capture fisheries has become depressed due to thedecline of wild resources and over fishing. Since the sustainable use of resourcesin the exclusive economic zone (EEZ) was made an obligation by the United
Nations Convention on the Law of the Sea, aquaculture technology R&D aimed
to maintain sustainable production while preserving coastal environments andecosystems have become the common issues to the US and Japan.
The UJNR Aquaculture Panel has discussed various science andtechnologies as follows: 1) algae and filter feeders aquaculture, 2) crustacean
aquaculture and pathology, 3) ecosystems and carrying capacity of aquaculture
grounds, and 4) finfish aquaculture in accordance with the 6th 5-years Plan
(2002-2006). During the last year of the plan, how to achieve sustainable fisheries
production and food supplies through aquaculture and stock enhancement will be
explored among aquaculture scientists as well as socio-economists and member ofgovernmental sectors, while summarizing discussions covering previously
developed aquaculture technologies.
In the present symposium, the following issues will be discussed in orderto promote the future sustainability of the fisheries community and fisheries
industry by means of aquaculture and stock enhancement.
1. Aquaculture technologies harmonized with coastal ecosystems to realize
sustainable production
2. Environmental conservation and mitigation technologies for sustainable use of
aquaculture grounds
3. Conservation of genetic diversities and ecosystems for sustainable of aquatic
resources
4. Sociological and economic measures for sustainable development and use ofcoastal resources-1-

Program

Monday, November 13th, 2006

Opening remarks

Registration(Yasuji Sakai, Japan Panel Chair)

Aim of the symposium (Kazumasa Ikuta)

13:00-14:00
14:00-14:10

14:10-14:15

Keynote presentation (Moderator: Kunihiko Fukusho & Conrad Mahnken)

14:15-15:00

An Overview of the US/Japan UJNR Aquaculture Panel, Past Present and Future
James P. McVey

Coffee break

15:00-15:15

Session I. Aquaculture technologies harmonized with coastal ecosystems to realize sustainableproduction (Moderators: Cheng-Sheng Lee & Takao Yoshimatsu)
1. Recent Progress in Closed Recirculation Seed Production System for Environmental
Preservation in Japan 15:15-15:45
Yoshihisa Yamamoto
2. Utilization of Waste Porphyra Products as Eco-friendly Feed Ingredients

15:45-16:15

Tsuyoshi Sugita
3. The Relationship between Growth of Cultured Red Sea Bream (Pagrus major) and Methodof Farming

16:15-16:45

Takashi Uede
4. Manila Clam and Pacific Oyster Culture in Isahaya Bay – For the Sustainable Production in
Stressful Environment -16:45-17:15

Junya Higano

Tuesday, November 14th, 2006

Registration

8:30-9:30

Keynote presentation (Moderator: Charles E. Helsley & Satoru Toda)

9:30-10:15

Recent Attempt towards Environmental Restoration of Enclosed Coastal Seas: Ago Bay
Restoration Project Based on the New Concept of “Sato Umi”
Osamu Matsuda-2-Coffee break

10:15-10:30

Session II. Environmental conservation and mitigation technologies for sustainable use of
aquaculture grounds(Moderators: Thomas A. Flagg & Hisashi Yokoyama)

1. The Role of Aquaculture in Integrated Coastal Management 10:30-11:00
Charles E. Helsley
2. New Technology for Developing Biologically Productive Shallow Area in Ago Bay
11:00-11:30
Hideki Kokubu
3. Stable Isotope Analyses of the Trophic Structure of Macrobenthos on an Artificial Tidal Flat
Developed using Sediments Dredged from Pearl-oyster Farms in Ago Bay 11:30-12:00
Yuka Ishihi

Lunch

12:00-13:00

Session III. Conservation of genetic diversities and ecosystems for sustainable use of aquatic(Moderators: William Fairgrieve & Kazumasa Ikuta)

resources

1. Introduced Species and Aquaculture 13:00-13:30
Cheng-Sheng Lee
2. Countermeasures against Alien Fish (Largemouth Bass and Bluegill) in Lake Biwa
13:30-14:00
Atsuhiko Ide
3. Conservation Aquaculture Approaches for Hatchery Reform 14:00-14:30
Thomas A. Flagg
4. Environmental Standards for Marine Aquaculture in the United States; Minimizing Negative
Interactions of Escaped Farm Fish and Natural Populations 14:30-15:00
Conrad Mahnken

Coffee break

15:00-15:15

Session IV. Sociological and economic measures for sustainable development and use of coastal
resources(Moderators: Hiroyuki Sudo & James J. Sullivan)

1. Economic Evaluation of Various Roles and Functions of Propagation and Aquaculture
15:15-15:45
Yasuji Tamaki-3-2. Risk and Risk Management for Feed and Seed for Carnivorous Marine Fish Aquaculture
15:45-16:15
Michael B. Rust
3. Ecological Risk Assessment of Marine Fish Aquaculture in the Coastal Zone
William Fairgrieve
4. The Measures for Sustainable Marine Aquaculture in Japan

16:45-17:15

Ikuo Takeda(Moderators: Michael B. Rust, Satoru Toda & Kazumasa Ikuta)

General discussion
17:15-17:30

Closing remarks(Robert Iwamoto, U.S.A. Panel Chair)-4-

17:30-17:45

16:15-16:45

Keynote presentation 1

An Overview of the US/Japan UJNR Aquaculture Panel, Past Present and Future

James P. McVey
National Oceanic and Atmospheric Administration, Silver Spring, MD 20910-3282, U.S.A.
The UJNR was started by a proposal made during the Third Cabinet-Level Meeting of the
Joint United States-Japan Committee on Trade and Economic Affairs in January 1964. The
United States and Japanese counterpart panels on aquaculture were formed in 1969 under theUnited States-Japan Cooperative Program in Natural Resources (UJNR).
The panels currently include specialists drawn from the federal departments mostconcerned with aquaculture and, on the US side, Sea Grant Directors responsible for
conducting research programs on aquaculture funded by the National Oceanic andAtmospheric Administration (NOAA). Charged with exploring and developing bilateral
cooperation, the panel has focused efforts on exchanging information related to aquaculture
which could be of benefit to both countries.

-5-Presentation I-1

Recent Progress in Closed Recirculation Seed Production System for Environmental
Preservation in Japan

Yoshihisa Yamamoto
Yashima Station, National Center for Stock Enhancement, Fisheries Research Agency,
Kagawa 761-0111, Japan
Recently, there have been some problems with mariculture in Japan, and the most serious
problem is self-pollution by mariculture using net cages. In some reports on nitrogen balance,
it was shown about 70 % of total nitrogen by mariculture using net cages was discharged into
the coastal waters. From the viewpoint of coastal environmental preservation, a closed
recirculation system is spotlighted for rearing technology that is a type of “Zero Emission” by
few discharges from fish rearing. Complete system control has led to a lot of benefits whichare (1) reduction of pollution, (2) avoidance of external risks (e.g. disease and bad water
quality etc.), (3) highly stable productivity, and (4) energy-saving effect. Therefore thedevelopment of efficient closed recirculation system and rearing technology using this system
will be demanded quickly for formation of commercial scale rearing technology.
In the Yashima Station, NCSE, FRA, technical development of a closed recirculation
system for seed production in red sea bream was started in 2000. The closed recirculation
system in this center consists of a foam separation unit, an efficient bio-filtration system(filtrating materials volume is only 5% of the total water volume) and a UV system. Theirfunctions are the removal of organic matter in rearing water, nitrification and sterilization ofbacteria, respectively.
At present, we have been able to demonstrate most of above benefits in our experiments
and the technical results of seed production using this system are higher than those offlow-through rearing. By using a closed recirculation system, (1) water exchange rate isminimal (below 0.5%/day). Therefore we can establish a near-perfect no discharge system forseed production. (2) In case of tiger puffer, avoidance of disease (Vibrio anguillarum) was
achievable. (3) Survival rate and production densities of red sea bream from hatched larvae tojuveniles of 30 mm in TL consistently reached 45~70 % and 5,000~7,000 individuals /kl
respectively and highest density of 20,000 individuals /kl was achieved for 25 mm in TL. (4)As a result of estimation of seedling cost, advantages of running cost for keeping suitable
rearing water temperature was found. Also for water quality, concentrations of ammonia
nitrogen and nitrite-nitrogen in rearing water were kept below 1.0mg/l and 0.5mg/l,
respectively. Therefore under the condition of minimal water exchanging rate, seedproduction by closed recirculation system is kept in suitable water conditions for survival andgrowth of juveniles.
For environmental preservation, we will try the newly developed waste treatment system
by safety biological and physical methods and integrated aquaculture using biologicaleco-system which utilizes the nitrogen cycle, (e.g. phytoplankton, seaweed, shellfish, sea
cucumber and polyceates). In the future, as the strategy for environmental preservation, it isnecessary that the Japanese Government support new companies which use the closed
recirculation aquaculture system and aquaculture companies which convert to the aquaculture
system from net cage rearing to closed recirculation system for the reduction of self-pollution.

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Presentation I-2

Utilization of Waste Porphyra Products as Eco-friendly Feed Ingredients

Tsuyoshi Sugita, Takeshi Yamamoto, and Takao Yoshimatsu
Aquaculture Systems Division, National Research Institute of Aquaculture,
Fisheries Research Agency, Mie 516-0193, Japan
Fish meal is an important feed ingredient for fish feeds because of its high nutritive value.
However, the supply of feed-grade fish meal has recently been coming short due to the
reduction of its production and increasing demand for formula feed production in the world.
On the other hand, environmental pollution by nitrogen and phosphorus loading from fish
farming has become a serious problem. Although the deterioration of water quality byphosphorus could be reduced using plant protein sources, the reduction of nitrogen emission
could be achieved by reducing the dietary protein content with alternative dietary amino acids
being balanced. Therefore, developing low or non-fish meal diets would become a promisingmean to solve these problems. Nori, Porphyra spp. (red algae, purple laver) are commerciallyand culturally important species used widely as Japanese traditional foods. Nori products also
contain high amounts of taurine, which is an important amino acid for marine fish, in addition
to minerals and vitamins. In this paper we summarize our trials to develop an eco-friendly
fish feed using waste nori of no commercial value.
Fingerling red sea bream Pagrus major (average body weight 10.1 g) were fed for 10
weeks on an optimal fat and protein (11 and 55 %) control diet and 2 experimental diets highfat and low protein (19 and 42 %, 25 and 36 %). All diets were supplemented with 5 % waste
nori. Weight gain, specific growth rate and feed efficiency for the diet containing medium fatlevel were not different compared with those for the control diet, whereas those for the dietcontaining the highest fat level noted the lowest values among the diets. These findings
suggest that dietary protein content can be effectively reduced from 55 % to 42 % bysupplementing 5% waste nori in diets.

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Presentation I-3

The Relationship between Growth of Cultured Red Sea Bream (Pagrus major)and Methods of Farming

Takashi Uede and Terufumi Takeuchi
Fisheries Experimental Station of Wakayama Prefecture, Wakayama 649-3503, Japan
Wakayama Prefecture is located in the southwest of Honshu Island, Japan. The aquacultureindustry is an important industry in Wakayama that occupies 1/4 of the total amount of all
fishery products. The main aquaculture target fish is red sea bream (Pagrus major), and it
reaches 80% of the total aquaculture production. In 1980's, the deterioration of the sedimental
environment and the frequent occurrence of red tide were observed with an increase in theaquaculture production in Tanabe Bay where is one of the biggest aquaculture sites of ourprefecture. After 1990's when the production had decreased by the depression of the fishvalue, both of these problems were improved. Hence, the environment of the Bay and theaquaculture production are regarded to be closely related by these findings. Therefore, toestablish efficient use of the fish farming ground, we conducted a series of test researchconcerning rearing conditions of red sea bream. We introduce the following three cases here.
Loads of discharged of leftover feed and feces in red sea bream farming
Some 3.6~15.6% of extrude pellets (EP) fed were discharged as leftovers and7.7~21.8% of them were discharged as feces. In case of moist pellets (MP), discharged
proportions of leftovers and feces were 10.1~19.2％, 12.8~30.0%, respectively. As a result,necessary amount (in dry weights) of EP to satiate the cultured red sea breams is 2.18 times
greater than that of MP. Amount of feed particles discharged in the case of EP feeding is 2.92
times greater than the case of MP.
Relationship between feeding frequency and growth of red sea bream
Red sea breams (130 ind., average weight 300 g) were distributed in three fish cages(22.5 m3), and feeding experiments were conducted for 225 days from March 14, 2003. The
feeding frequencies were four (Ex.1), three (Ex.2) and two (Ex.2) times a week, respectively.
As a result, the best growth was obtained in the fish cage of Ex.1 with high feeding frequency.
Moreover, the growth of Ex.1 was better than the average fish growth obtained in threeprivate farms in the prefecture. Therefore, the growth of red sea bream was enhanced with theincrease of the feeding frequency.
Relationship between Edwardsiella disease outbreak and breeding densities
Red sea breams (average weight 410g) were distributed in the four fish cages (22.5 m3)
with the densities of 2.4 (Ex.1), 3.6 (Ex.2), 4.7 (Ex.3) and 5.7 kg/m3 (Ex.4), respectively, andrearing experiment was carried out for 140 days from April 9, 2004. The mortality of red sea
bream in Ex.2 due to the outbreak of Edwardsiella disease increased rapidly from the 100thday, although the best fish growth was maintained until the 130th day. Mortality gradually
spread to Ex.3 and 2, and it occurred in Ex.1 after 130th days. As a result, when the rearing
trial terminated, the stocking densities of Ex.2~4 became 4.8~5.7 kg/m3 of the same level.
Cumulative mortality rates of Ex.1~4 were 13.9, 11.8, 37.7, 48.7%, respectively, and affected
its stocking density.
.

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Presentation I-4

Manila Clam and Pacific Oyster Culture in Isahaya Bay-For the sustainable production in stressful environmentJunya Higano1, Keiji Hirano2, Shigeru Kitahara2, Masahiko Matsuda2,
Kouji Mizuta2, Akihiko Fujii2, and Akira Shinagawa3
1

Aquaculture Systems Division, National Research Institute of Aquaculture,
Fisheries Research Agency, Mie 516-0193, Japan

2

Nagasaki Prefectural Institute of Fisheries, Nagasaki 851-2213, Japan

3

Gakushuin Women's College, Tokyo 162-8650, Japan

Isahaya Bay is a branch of Ariake Sound, Kyushu, where tidal range is the largest in Japan.
Penshell, Atrina pectinata, was dominant fisheries product in Konagai Fisheries Cooperativeand caught by means of diving equipments. However, after the construction of Isahaya
Reclamation Project it was diminished in 1990s. Culture of Manila clam, Ruditapes
philippinarum, commenced 1970s and is currently the most important industry in the
Cooperative. The marked characteristics of the clam culture in the Cooperative are
introduction of demarcated fishery for Manila clam culture under common fishery right,
individual management of culture ground such as sand placement on muddy substrate andseveral facilities for accumulating the juvenile clams and preventing predators, registeredlanding under the cooperative sales. The annual landing normally reaches 400-700t for ca.
100 individual fishermen. But Manila clam culture occasionally suffered from mass mortality
in summer season since 1998 when the barrage in Isahaya Reclamation closed in the previous
year. We studied about the mass mortality from the aspects of environment and physiology of
the clam and elucidated that the main cause of mass mortality was anoxia by mean ofcontinuous monitoring of water quality factors and analysis of organic acids in the pallial
cavity fluid of Manila clams.
For sustainable and stable production of Manila clam, prediction and prevention ofanoxic water intrusion to the culture ground are foremost important. Suspended culture ofPacific oyster, Crassostrea gigas, was introduced in late 1990s in Isahaya Bay which had
naturally been produced delicious native oysters inhabited near the shoreline. The oyster
culture industry has grown up to 175t of annual production by 42 fishermen in 2005. The
oyster culture contributes to compensate for the reduction of Manila clam production. The
seeds of cultured oyster were transported from Miyagi Prefecture, northern Japan. The growthof cultured oyster is very well and is able to harvest the excellent quality oysters in only halfyear growout culture. However, there are several problems for constricting the increase of the
production, namely, summer mortality after spawning, heavy fouling by barnacles and lower
consumer's demand in local market, etc. Exploit of the market demand and improvement of
the culture technique are necessary.
.

-9-Keynote presentation 2

Recent Attempt towards Environmental Restoration of Enclosed Coastal Seas:
Ago Bay Restoration Project Based on the New Concept of “Sato Umi”

Osamu Matsuda
Professor Emeritus, Hiroshima University
Core Research Laboratory, Ago Bay Restoration Project, MIESC, Mie 517-0501, Japan
Since the present status of the enclosed seas along the coast of Japan is more or less"damaged" or "deteriorated" mainly due to prolonged impact of human activities,
environmental restoration followed by rehabilitation of natural ecosystem is one of the mostimportant subject to be tackled from the view point of both environment and natural resources.
Among 88 officially designated enclosed coastal seas in Japan, Ago Bay is one of thedeteriorated bay especially from the view point of aquaculture ground. Although the bay is
known to be a world-famous cradle of pearl culture, conditions of the bay in terms of
sediment quality, dissolved oxygen and harmful algal blooms have been deteriorated during
the long history of pearl culture spanning more than 100 years.
The ongoing “Environmental Restoration Project on Enclosed Coastal Seas in Ago Bay”
conducted under the CREATE program of Japan Science and Technology Agency mainly
deals with restoration of deteriorated tidal flats and sea grass beds and also development ofenvironmental forecasting technology based on the environmental monitoring and modeling.
Since the project includes not only scientific and technological studies but also includes
components of environmental education, environmental management and wider cooperation
with varieties of stakeholders, it can be a model of environmental restoration andmanagement of enclosed coastal seas.
Outline of the project as well as the present status and future perspective will be
introduced in the presentation with particular emphasis on the new concept of “Sato Umi”.
“Sato Umi” in Japanese means coastal sea under the harmonization of sustainable wise usewith conservation of appropriate natural environment and habitat conditions. Compared withdeteriorated coastal environment, “Sato Umi” is able to provide higher biological diversity for
habitat and higher biological productivity for living resources. These characteristics of “SatoUmi” are also suitable site for demonstrating multi-functional roles of fisheries. Restoration
method for damaged shallow environment and habitat with use of environment friendly
technology based on the concept of “Sato Umi” is being developed and applied in Ago Bay.

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Presentation II-1

The Role of Aquaculture in Integrated Coastal Management

Charles E. Helsley
School of Ocean and Earth Science and Technology
University of Hawaii, Honolulu, Hawaii, HI 96822, U.S.A.
Coastal ecosystems have evolved to be in balance with the supply of nutrients from oceanic
upwelling and runoff from land. Over or under supply of these essential nutrients can upset
this balance and shift the ecosystem in undesirable way, at least undesirable from a humanperspective.
Most coastal ecosystems are no longer in balance with the supply of nutrients foranthropogenic effects on shore and in the immediate offshore have greatly modified thenatural system. Aquaculture can contribute to this problem or it can be practiced in an
extractive mode and thus be used as a means of balancing this equation. Nutrient extractive
aquaculture includes the culture of seaweeds (algae) and bivalves. It is also possible thatcertain filter feeding fish could also be used in this mode.
Models of ecosystem management can incorporate both extractive and additive
aquaculture but most applied aquaculture does not follow these models for the economics ofproduction and use of manpower and equipment heavily favors the nutrient additive forms ofaquaculture. Nevertheless, it is instructive to examine the more balanced form of aquaculture
to see if it can make economic sense.

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Presentation II-2

New Technology for Developing Biologically Productive Shallow Area in Ago Bay.

Hideki Kokubu and Hiroyuki Okumura
Fisheries Research Division, Mie Prefectural Science and Technology Promotion Center,
Mie, 517-0501, Japan
Ago Bay is located in Ise-Shima National Park and is famous for the cradle of pearl culture.
However, harmful algal blooms and infectious diseases make sustainable pearl culture
difficult. Furthermore, sediment eutrophication and frequent occurrence of oxygen-deficientwater has caused the deterioration of benthic ecosystem and decrease of biologicalproductivity in recent years. It is considered that one of the major causes of these phenomena
is stagnation of the material circulation by reduction of shallow coastal area including a tidal
flat, sea glass and sea weed beds. The natural shallow coastal areas were decreased
everywhere in inner parts of the bay by land reclamation and the dike construction. Then we
made clear by the multi-spectrum aerial picture analysis that approximately 70% of tidal flatand shallow areas have been already decreased in Ago Bay. Therefore, for environmental
restoration of Ago Bay as the major site of pearl culture, it is necessary to enhance thebiological productivity which tidal flat, sea glass and sea weed beds provide, and to recover asmooth material circulation around the shallow areas. We developed new technology forenhancing biological productivity by controlling sediment quality.
To determine the suitable sediment condition for the benthic species, we set up the six
experimental tidal flats in which the organic content was changed. And sediment quality andbenthic species of experimental tidal flat study areas have been monitored for 3 years. Thenthe suitable range of sediment quality condition of tidal flats for benthic species was found tobe 3-10mg/gDW for COD and 15-35% for mud content ratio. By utilizing above result, wedeveloped new technology to enhance the biological productivity in these following two typesof shallow areas by controlling sediment condition.
Tidal flat in front of dikeIn front of the dike, there are relatively oligotrophic tidal flats everywhere in Ago bay.
These areas are about 84ha. These sediment of tidal flats are gravel and contain low organic
matter, because the dike shut out the nutrient supply from the land. So, in these tidal flat, theabundance and diversity of benthos are very low. Then to enhance the biological productivity,
we developed new artificial tidal flat using muddy dredged sediment which contains
rich-organic matters and is usually treated as a useless material in Ago Bay. We constructed
about 7200m2 of artificial tidal flat with mixing muddy dredged sediment and oligotorophic
sediment existing in front of dike. Then we investigated the sediment quality, benthic
abundance and species diversity every season for 2 years. In this investigation, it is clear thatfor about 1 year the abundance and diversity of benthos were increased more than 4 times andthe biologically productivity becomes high compare with the condition before construction.
Unused wetland behind the dike
Behind the dike, there are hypertrophic unused wetlands everywhere in Ago bay. These
areas are about 153ha. These sediment of tidal flats are muddy and contain high organic
matter, because the dikes store the nutrient supply from the land. So, in these wetlands, theabundance and diversity of benthos are very low. To enhance the biological productivity, weare developing the new technology to reduce the organic matter by promoting water exchange
between wetland and outer sea. We set up the experimental field in which the water exchange
is simulated natural tide by pumps. Now we are investigating the sediment quality, benthic
abundance and species diversity every season in this project.

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Presentation II-3

Stable Isotope Analyses of the Trophic Structure of Macrobenthos on an Artificial
Tidal Flat Developed using Sediments Dredged from Pearl-oyster Farms in Ago Bay

Yuka Ishihi and Hisashi Yokoyama
Aquaculture Systems Division, National Research Institute of Aquaculture,
Fisheries Research Agency, Mie 516-0193, JapanIn Ago Bay, an artificial tidal flat was developed during the period from December, 2003 to
May, 2005 by spreading organic enriched sediments that had been dredged from pearl oyster
farms in this bay over a sandflat. We investigated the trophic structures of the macrobenthos
on this intertidal flat before (November, 2003) and after (November, 2005) the developmentof the artificial tidal flat using the stable carbon and nitrogen isotope technique in order toevaluate the effect on the macrofaunal trophic structure of the macrobenthos.
Results show that (1) before the development of the artificial tidal flat, consumers wereclassified into 4 groups; suspension feeders that were composed mainly of bivalves (range ofmean δ13C values = -19.5 to -18.0 ‰, range of mean δ15N values = 8.7 to 9.9 ‰), deposit
feeders and grazers that were composed of gastropods and ocypodid crabs (δ13C = -14.8 to-10.7‰, δ15N = 6.7 to 9.8 ‰), omnivores that were composed of a variety of taxa including
gastropods, polychaetes, hermit crabs and grapsid crabs (δ13C = -16.6 to -13.2 ‰, δ15N = 9.5
to 10.7 ‰) and carnivores that were composed of sea anemones and polychaetes (δ13C =-17.8 to -13.9 ‰, δ15N = 12.2 to 13.7 ‰) and (2) after the development of the artificial tidal
flat, consumers were classified into 3 groups; suspension feeders (δ13C = -18.6 to -17.0 ‰,δ15N = 8.2 to 9.9 ‰), deposit feeders and grazers (δ13C = -14.5 to -11.0 ‰, δ15N = 7.0 to
9.0 ‰) and omnivores (δ13C = -16.7 to -12.9 ‰, δ15N = 9.1 to 10.1 ‰).
These results indicated that the development of the artificial tidal flat eliminatedcarnivores, led to an increase in the δ13C of the suspension feeders and a decrease in the δ13Cof the deposit feeders and grazers. It seems that the observed increase of δ13C values for thesuspension feeders resulted from the incorporation of benthic microalgae (δ13C = -15.9 ‰,δ15N = 5.7 ‰) that grew abundantly on the mudflat as well as coastal phytoplankton (δ13C =-21.5 ‰, δ15N = 7.5 ‰) and that the decrease of δ13C values for the deposit feeders resulted
from the incorporation of organic matter that was contained in the dredged sediments (δ13C =-19.0, δ15N = 5.8).

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Presentation III-1

Introduced Species and Aquaculture

Cheng-Sheng Lee
Oceanic Institute, Waimanalo, Hawaii, HI 96795, U.S.A.
Even though the current main sources of seafood come from capture fisheries, the total yieldfrom this source reached a plateau in 1990 and no further significant growth is expected in
capture fisheries. Aquaculture contributions have increased significantly since 1970 and now
account for more than 37.5% of all fish consumed in 2003 (FAO, Fishstat). From 1950 to2003, a total of 416 aquatic species have been cultured at least once. In 2003, of these species,
314 had production of one tonne or more.
Problems associated with the culture of local species led culturists to seek related
non-indigenous species as alternatives (Stickney, 2001). Aquaculture as the main reason
accounts for 38.7% of introduced species recorded in Food and Agriculture Organization(FAO) database (Garibaldi and Bartley 1998). The practice of culturing non-indigenous
species has existed for many years to take advantage of existing markets, and available
technology and resources. Almost 10% of world aquaculture production came fromintroduced species (Garibaldi and Bartley 1998). Following the expansion of aquaculture
production and the increasing demand of diversified seafood from consumers, the pressure toculture non-indigenous species has increased.
Aquaculture farms in the U.S. currently produce more than 100 different species ofaquatic plants and animals; most major aquatic species cultured in the U.S. are not native totheir farm sites (Naylor et al., 2001). Non-indigenous species have been introduced forfarming in particular regions because of the immediate social and economic benefits. Some
non-indigenous species, however, have quickly adapted to the new environment, become
established, and compete with indigenous species for limited habitats. Biological invasions
are recognized as serious threats to marine biodiversity and ecosystem structure and function(Frisch and Murray, 2002). In addition, introduction of non-indigenous species foraquaculture has resulted in numerous unintentional introductions of pathogens, parasites, andpest species (Galil, 2000).
This presentation will review the significance of introduced species in total aquaculture
production. The culture of marine shrimp will be used as an example to explain the impacts
on surrounding environments in both physical and biological aspects. To keep the positive
contribution of introduced species in aquaculture, certain measures must be developed to
avoid any negative impacts. Developing mitigation strategies and monitoring capabilities for
introduced species is very important to avoid negative impacts.

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Presentation III-2

Countermeasures against Alien Fish (Largemouth Bass and Bluegill) in Lake Biwa

Atsuhiko Ide and Shinsuke Seki
Shiga Prefectural Fisheries Experimental Station, Shiga 522-0057, Japan
Lake Biwa, located on the main island of Honshu, is the largest lake in Japan. It is also one of
the world’s most ancient lakes, with an origin going back four million years. Numerous
aquatic organisms, including more than 30 endemic species of fish and mollusk, inhabit thelake, and fisheries of various kinds have targeted these animals from ancient days. The total
annual commercial catch of fish and crustaceans was about 4000 metric tons during the 1970s
and 1980s.
Bluegill (Lepomis macrochirus) and largemouth bass (Micropterus salmoides) were firstfound in Lake Biwa in 1965 and 1974, respectively. While bluegill spread gradually throughthe bays and small lagoons surrounding the lake, largemouth bass increased explosively in the
1980s. Simultaneously, native fishes such as crucian carp and bitterlings disappeared from thecoastal shallows. After that, the population of bluegill began to increase and this species
replaced most of the remaining native shore fishes. In recent years, bluegill have constituted
over 90% of the fish fauna in Lake Biwa’s south basin, and the annual catch of commercial
species in the lake has decreased to half of that recorded in the 1970s and 1980s.
Since 1985, fishermen have been trying continuously, by several means, to reduce thesealien species. Fishing gear such as “eri” (a labyrinth-like set-net), gill nets, and pot traps havebeen used. Recently, about 400 metric tons per year of these alien fishes have thus been
eliminated.
At the same time, the Shiga Prefectural Fisheries Experimental Station has tried todevelop more effective gear to catch them. We have devised a pot trap with its top covered bya sheet to provide shade, for efficient capture of bluegill, and a small beam trawl for use inbeds of submerged aquatic plants. Other methods for the eradication of the alien fishes are
currently under study.

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Presentation III-3

Conservation Aquaculture Approaches for Hatchery Reform
Thomas A. Flagg1 and Lars E. Mobrand2
1

NOAA Fisheries, Northwest Fisheries Science Center, Resource Enhancement andUtilization Technologies Division, Manchester, Washington, WA 98353, U.S.A.

2

Hatchery Scientific Review Group, Mobrand-Jones & Stokes, Inc., Vashon, Washington,
WA 98070, U.S.A.

Theoretically, one of the fastest ways to amplify population numbers for depleted stocks isthrough culture and release of hatchery-propagated fish. However, past attempts to use
supplementation (i.e., the use of artificial propagation in an attempt to maintain or increase
natural production) to rebuild naturally-spawning populations have often yielded poor results.
The challenge is to develop hatchery reform protocols that increase fitness of hatchery-reared
fish, thereby improving survival. Considerable conservation aquaculture and ecologicalinteractions research has been conducted by the NOAA Fisheries, Northwest Fisheries
Science Center, Manchester Research Station that has helped address consequences ofhatchery reform actions.
In addition, NOAA is a partner in a formal process of hatchery reform that has beenongoing in the Pacific Northwest since 1999. The Hatchery Scientific Review Group (HSRG)
is funded by the U.S. Congress and is a systematic, science-driven redesign of how hatcheries
will be used to achieve the goals of: 1) helping to recover and conserve naturally spawning
populations, and 2) supporting sustainable fisheries. Initial work by the HSRG included
developing a Scientific Framework for Artificial Propagation of Salmon and Steelhead, aBenefit/Risk Assessment Tool, Hatchery Operational Guidelines, and Monitoring and
Evaluation Criteria. These tools are being used by the HSRG in a comprehensive
region-by-region review that evaluates hatchery programs for consistency with establishedscientific principles and the objectives of hatchery reform.
These combined efforts have resulted in operational guidelines for conservation
hatcheries to help mitigate the unnatural conditioning provided by hatchery rearing. These areinclude: 1) Mating and rearing designs that produce minimal genetic divergence of hatcheryfish from their wild counterparts to maintain long-term adaptive traits; 2) Simulation ofnatural rearing conditions through incubation and rearing techniques that approximate natural
profiles and through increasing habitat complexity (e.g., cover, structure, and substrate inrearing vessels) to produce fish more wild-like in appearance, and with natural behaviors andhigher survival; 3) Conditioning techniques such as anti-predator conditioning to increase
behavioral fitness; 4) Release of fish at a size, stage, and condition which approximates thewild population to reduce potential negative ecological interactions and to promote migratory
homing; and 5) Aggressive monitoring and evaluation to determine success of conservation
hatchery approaches.

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Presentation III-4

Environmental Standards for Marine Aquaculture in the United States; Minimizing
negative interactions of escaped farm fish and natural populations

Conrad Mahnken
NOAA Fisheries Service, Manchester Research Station, Manchester, WA 98353, U.S.A.
The National Offshore Aquaculture Act of 2005 was introduced in the United States Senate inJune 2005 and would establish a regulatory framework for offshore aquaculture in the UnitedStates. In addition to issuing permits and establishing research partnerships, NOAA would be
required to develop environmental standards that would protect the marine ecosystems inwhich offshore farms are to be located. One element of environmental standards is thepotential impact that escaped farm fish may have on local native stocks and species.
The rapid development of world cage farming of marine fishes has raised concerns overthe possible genetic and ecological impact of escaped fish on natural populations. Potential
effects include genetic alteration and reduced fitness, competition for food and space, andpredation on native stocks. It is important to review the potential impacts of escapedindigenous and non-native marine fish on localized native stocks in order to develop risk
assessment and management strategies. However, little data exists in the aquaculture, genetic,or ecological scientific literature on the interaction of farmed fishes escaped from aquaculture
facilities and native marine fishes. Therefore it is presently difficult to predict the actual
impact that escaped fish will have on their wild counterparts within the ecosystem.
There is some information available on the intentional release of marine fish species forpurposes of stock enhancement, however there are almost no data available on accidental
releases as applies to marine aquaculture. While intentional releases are intended to have a
noticeable and positive effect on natural populations of con-specifics by increasing stock size
and abundance, effects of accidental releases by species or number are considered to havenegative effects (ICES, 2002, 2003, 2004, 2005). It should be pointed out that this is notnecessarily true in all cases and depends on the genetic state of the escaped farm fish and thenumbers and mean individual size of the escaped population.
Note: This introduction section should also contain a discussion on: magnitude of salmon
escapes from marine farms (data rich), escapes of marine fish, mostly from the north Atlanticand Mediterranean farms and hatcheries (data poor), incidence of escapes from net pensinsofar as data is available (data poor), knowledge on genetic and ecological interactions
resulting from marine enhancement releases (data poor); and information on genetic stock
structuring necessary to estimate the potential for negative interaction on natural fish
populations.
Paucity of scientific information on the real genetic and ecological consequences of
escaped farm fish makes it difficult to predict the negative interaction on natural fish
populations. Therefore, environmental standards in Canada, the EU and Chile are aimed atpreventing escapes in the first place through production monitoring, engineering ofcontainment systems, best management practices, and methods to recover escaped fishes.
Because hard scientific data is lacking, environmental standards are narrative rather thanquantitative. Proposed environmental standards for the United States will include theseelements plus the need for applying a numerical model as a planning tool for navigating thecomplexities potential genetic and ecological interactions.

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Presentation IV-1

Economic Evaluation of Various Roles and Functions of Propagation andAquaculture
Yasuji Tamaki
Fisheries Economy Division, National Research Institute of Fisheries Science,
Fisheries Research Agency, Kanagawa 236-8648, JapanI performed an economic evaluation of various roles of aquaculture, apart from its primaryrole in supplying marine products.
I defined these secondary roles as "provision of food security", "environmental improvement","exchange between urban and fishing communities", "maintenance of traditional culture", and"formation and maintenance of local communities" .
In 2005, aquaculture without artificial feeding removed 6,090 t nitrogen and 595 t
phosphorus from Japan’s coastal seas. The economic value of this reduction in pollution was
equivalent to 1298 hundred million yen in the cost of sewage treatment of this amount ofwaste.
From the results of a questionnaire-based investigation of the general population, I
estimated by the CVM (Contingent Valuation Method) that non-use value of algae groundaround Japan was 553 to 2109 hundred million yen.

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Presentation IV-2

Risk and Risk Management for Feed and Seed for Carnivorous Marine Fish
Aquaculture

Michael B. Rust
NOAA Fisheries Service, Northwest Fisheries Science Center, Seattle, WA 98112, U.S.A.
The provision of feed and seed for marine fish aquaculture often occurs external to the actual
fish culture operation. How those external activities are conducted and applied impacts thepotential ecological risk for the entire industry. Up stream ecological risks associated withfeed and seed from culture of carnivorous marine fish aquaculture include the potential forover-fishing due to demand for wild juveniles for grow-out, and harvesting industrial fisheries
for aquafeeds. Downstream ecological risk associated with feed includes organic loading andbenthic impacts. Downstream risks associated with seed are associated with the potential
ecological and genetic impacts of escapes on conspecific wild stocks if the cultured fish is
native or ecological impacts on native species if the escapees are non-native. For each risk,
the WHO risk assessment framework may be applied to focus research and development on
strategies that could be used to manage or eliminate the risk. I suggest that situations where
economic gain and ecological risk reduction are in-line are preferred and have a much higher
chance of resulting in meaningful improvements. In both up stream cases, proper fishery
management can reduce risk at a low level of demand, however at some higher levels of
demand, substitution (i.e. hatchery development and alternative feedstuffs) provides a better
option. In both later cases, economic gain is in line with ecological risk improvements,
making adoption more likely. The development and adoption of formulated feeds over raw
fish diets greatly reduces the organic pollution associated with fed fish aquaculture. Further
refinements in diet formulation and processing can further reduce the organic loads associatedwith fed fish aquaculture. Gains in feed technology are also in line with economic gains oncea critical level of production is reached. Risk associated with escapes can be managed at thehatchery by either raising fish with the same genetic make-up as wild stocks, or bydomestication of the farmed species to reduce escapees’ fitness in the wild. In this case,economic gains would favor domestication and not maintaining a wild stock genotype.
Governments can create win-win situations by fostering research and development where
ecological risk and economic gains are in line and both considered. In the case of feed andseed, this would include development of high quality compound feeds and hatcheries withassociated selective breeding programs for new and existing marine fish industries.

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Presentation IV-3

Ecological Risk Assessment of Marine Fish Aquaculture in the Coastal Zone

William Fairgrieve and Colin E. Nash
Pacific States Marine Fish Commission, c/o NOAA Fisheries Service Manchester Research
Station, Manchester, WA 98353, U.S.A.
The presentation summarizes the proceedings of an international workshop organized todevelop “Guidelines for the Risk Assessment of Marine Fish Aquaculture” (see:http://www.nwfsc.noaa.gov to download proceedings). The international participants adopted
the structural approach to risk assessment developed by the World Health Organization(WHO), and which is now widely used. For each risk, the WHO framework begins withproblem formulation, and proceeds through problem analysis to characterize the exposure andecological effects of the risk before the final risk characterization. It ends with risk
management. In addition to explaining the Risk Assessment Framework and its application ina global marine aquaculture setting, the Guidelines include ten example templates. Eachtemplate applies the process to a risk currently perceived by scientists or the public to havepossible impact on the coastal and marine ecosystems depending on specific ecologicalconditions of various biogeographical zones and in a variety of other circumstances. The tenrisks are: increased organic and inorganic loading, residual heavy metals in sediments,
transmission of disease between wild and farmed populations, residual therapeutants insediments, biological interactions of escapees with wild populations, physical interactions
with marine wildlife, physical impacts on marine habitats, using wild juveniles for grow-out,and harvesting industrial fisheries for aquafeeds. Included in each risk template are sections
on the current hypothesis for perception of the risk, the background experience or known
information, the conceptual model of how the risk is manifest, its analysis andcharacterization, and finally a biological opinion regarding its possible incidence andmanagement or prevention.

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Presentation IV-4

The Measures for Sustainable Marine Aquaculture in Japan

Ikuo Takeda
Fish Ranching and Aquaculture Division, Fisheries Agency, Tokyo 100-8907, Japan
Marine aquaculture in Japan has developed steadily since the 1960’s, and it occupies animportant position in the Japanese marine fisheries at this stage. In 2004, it accounted for 21.4
percent of the total production and 29.0 percent of the total value. Accordingly, theachievement of sustainable marine aquaculture is one of the important issues when
considering Japanese fisheries policy. This paper outlines several measures and basic plan
related to sustainable development of Japanese marine aquaculture.

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Paper Presenters list
Japan
IDE, Atsuhiko
Shiga Prefectural Fisheries Experimental Station, Shiga 522-0057, Japan+81-749-28-1611, +81-749-25-2461 (Fax)
gf30@pref.shiga.lg.jp
ISHIHI, Yuka
Aquaculture Systems Division, National Research Institute of Aquaculture,
Fisheries Research Agency, Mie 516-0193, Japan+81-599-66-1830, +81-599-66-1962 (Fax)ishihi@fra.affrc.go.jp
UEDE, Takashi
Fisheries Experimental Station of Wakayama Prefecture, Wakayama 649-3503, Japan+81-735-62-0940, +81-735-62-3515 (Fax)uede_t0001@pref.wakayama.lg.jp
KOKUBU, Hideki
Fisheries Research Division, Mie Prefectural Science and Technology Promotion Center,
Mie 517-0501, Japan+81-599-43-5102, +81-599-43-1172 (Fax)kokubhoo@pref.mie.jp
SUGITA, Tsuyoshi
Aquaculture Systems Division, National Research Institute of Aquaculture,
Fisheries Research Agency, Mie 516-0193, Japan+81-599-66-1830, +81-599-66-1962 (Fax)sugisan@fra.affrc.go.jp
TAKEDA, Ikuo
Fish Ranching and Aquaculture Division, Fisheries Agency, Tokyo 100-8907, Japan+81-3-3502-8111
ikuo_takeda@nm.maff.go.jp
TAMAKI, Yasuji
Fisheries Economy Division, National Research Institute of Fisheries Science,
Fisheries Research Agency, Kanagawa 236-8648, Japan+81-45-788-7615, +81-45-788-5001 (Fax)tamakiy@affrc.go.jp
HIGANO, Junya
Aquaculture Systems Division, National Research Institute of Aquaculture,
Fisheries Research Agency, Mie 516-0193, Japan+81-599-66-1830, +81-599-66-1962 (Fax)
higa@fra.affrc.go.jp
MATSUDA, Osamu
Core Research Laboratory, Ago Bay Restoration Project,
Mie Prefectural Science and Technology Promotion Center, Mie 517-0501, Japan+81-599-43-5102, +81-599-43-1172 (Fax)o-masuda@miesc.or.jp
YAMAMOTO, Yoshihisa
Yashima Station, National Center for Stock Enhancement,
Fisheries Research Agency, Kagawa 761-0111, Japan+81-87-841-9241, +81-87-841-9242 (Fax)yama1215@fra.affrc.go.jp- 22 -

U.S.A.
FAIRGRIEVE, William
Pacific States Marine Fish Commission, NOAA Manchester Research Station,
P. O. Box 130, Manchester, WA 98353, U.S.A.
+1-360-871-8305, +1-206-842-8364 (Fax)william.fairgrieve@noaa.gov
FLAGG, Thomas
NOAA Manchester Research Station, P. O. Box 130, Manchester, WA 98353, U.S.A.
+1-360-871-8305, +1-206-842-8364 (Fax)
tom.flagg@noaa.gov
HELSLEY, Charles E.
School of Ocean and Earth Science and Technology, University of Hawaii, Honolulu,
HI 96822, U.S.A.
+1-808-956-2873, +1-808-956-3014 (Fax)chuck@soest.hawaii.edu
LEE, Cheng Sheng
Center for Tropical and Subtropical Aquaculture, The Oceanic Institute,
Waimanalo, HI 96795, U.S.A.
+1-808-259-3107, +1-808-259-8395 (Fax)cslee@oceanicinstitute.org
MAHNKEN, Conrad
NOAA Manchester Research Station, P. O. Box 130, Manchester, WA 98353, U.S.A.
+1-360-871-8301, +1-206-842-8364 (Fax)conrad.mahnken@noaa.gov
MCVEY, James
National Sea Grant College Program, Office of Oceanic and Atmospheric Research,
National Oceanic and Atmospheric Administration, Silver Spring, MD 20910-3282, U.S.A.
+1-301-713-2451, +1-301-713-0799 (Fax)jim.mcvey@noaa.gov
RUST, Michael B.
Marine Research Group, Resource Enhancement and Utilization Technologies Division,
Northwest Fisheries Science Center, Seattle, WA 98112, U.S.A.
+1-206-860-3382, +1-206-860-3467 (Fax)mike.rust@noaa.gov
UJNR Aquaculture Panel Chairs (2006)
Japan SAKAI, Yasuji
Director General, National Research Institute of Aquaculture,
Fisheries Research Agency, Mie 516-0193, Japan+81-599-66-1830, +81-599-66-1962 (Fax)sakaiy@fra.affrc.go.jp
U.S.A. IWAMOTO, Robert
Division Director, OMI Division, Northwest Fisheries Science Center, Seattle, WA 98112, U.S.A.
+1-206-860-3200, +1-206-860-3467 (Fax)
bob.iwamoto@noaa.gov- 23 -

Note- 24 -