Sustainable Aquaculturefor a Secure Future

POND DYNAMICS/AQUACULTURE COLLABORATIVE RESEARCH SUPPORT PROGRAM NEWSLETTER

Volume 15, Number 3/Summer 2000 <pdacrsp.orst.edu> ISSN 1062-4996

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Inside Aquanews…

More Kenya News2–5

Thesis Abstracts3, 7, 8

CRSP Researcher Profile: Upton Hatch5

Student Profile: John Hayes6

EEP Site Visit9

ISTA V/IIFET 200010

Updates from around the Globe11

Publication Notices6–7, 12–13

Conferences and Workshops14–15

CRSP Kenya Communiquéby Jim Bowman (Oregon State University, US Regional Coordinator, Kenya Project)and Karen Veverica (Auburn University, Co-Principal Investigator, Kenya Project)

I t’s been just three years sinceKaren Veverica, the KenyaProject’s resident US researcher,

arrived at Sagana, and during thisshort time a lengthy list of achieve-ments has been accumulated. On herarrival at Sagana Fish Farm in April1997, Veverica immediately began thetask of helping prepare the facility forCRSP experiments and for serving asan information center for aquaculturein the region.

The first priorities in preparing thesite for CRSP work included con-verting three of Sagana’s 4,000-m2

production ponds into twelve more

manageable 800-m2 research ponds,expanding the existing laboratoryspace to hold the additional instru-ments and apparati needed toconduct water quality tests requiredby CRSP protocols, and assemblingand installing a complete newweather monitoring system for thestation. Fingerling production wasimproved, and staff needed to betrained in moving large numbers oflive fish, keeping data, and managingponds. Most of the work in thesethree areas was completed by the endof October 1997, with automatic,continuous weather monitoringbeginning at the end of Novemberand the first CRSP experiment(Eighth Work Plan) being initiated inthe new ponds at the beginning ofDecember. Since that time the CRSPresearch ponds at Sagana have beenin continuous use. The sequence ofexperiments and dates of researchpond use at Sagana are shown on p. 2.

Under Veverica’s supervision, pondconstruction crews at Sagana havebeen able to continue renovating andimproving more of the older ponds atSagana. As of this writing, 25 matched,800-m2 research ponds, four miscella-neous ponds of 800 to 880 m2 each,and three smaller ponds (150 m2

each) have been created throughthese efforts; an additional large pond(about 1 acre) is currently beingrenovated. The Fisheries Departmenthas asked that revenues from CRSP-generated fish sales be used towardsbuilding more 150-m2 ponds.

Education and Training

Probably the most important work thatthe Kenya Project has undertaken hasbeen in the area of training. This hasbeen accomplished through formalproject activities such as the provisionof scholarship support for studentsundertaking master’s programs and aseries of short courses for KenyanFisheries officers and extension agents.For example, the master’s programs oftwo students are fully supported bythe CRSP. These include BethuelOmolo, currently studying at AuburnUniversity in the US (see relatedarticle, p. 4), and Robertson Mugo,who is working at Moi University inEldoret, Kenya. In addition, three

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Charles Kariuki (far left), head of the seine crew,works with Kenyan university students

(standing, left to right) Paul Wamwea, WilliamNyaga, Cosmas Mungo, Jedidah Atieno, DanielMirera, and (front) Enos Were to weigh fish on

pond sampling day at Sagana Fish Farm.

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Kenya Project…from p. 1 KENYA LINKAGES 2000

Two significant new linkages to the Kenya Project havebeen established in 2000. The first is an agreementto work hand-in-hand with the Moi UniversityDepartment of Fisheries (Eldoret, Kenya) on our trainingprograms for Kenyan Fisheries officers, extension agents,and farmers (see main story). Dr. David Liti, of theDepartment of Zoology at Moi University, is helpingoversee operations and advising students at SaganaFish Farm when Karen Veverica is not in Kenya. Hewill return to Eldoret in September 2000. In additionto Dr. Liti, Moi University faculty now collaboratingwith the CRSP and the Kenya Fisheries Departmentinclude Dr. Mucai Muchiri, Head of the Departmentof Fisheries, and Dr. Charles Ngugi, lecturer in theDepartment of Fisheries. We expect that this collaborationwith Moi University will lead to a productive and long-term partnership between the Kenya Fisheries Departmentand Moi University Department of Fisheries.

The second new linkage established this yearallows the CRSP and ICLARM-Malawi to conductcompanion site research at Malawi’s National AquacultureCenter (Zomba) and at Bunda College. Students fromBunda College of Agriculture will be involved in studiesat both sites. Overall supervision of these efforts willbe provided by Dr. Daniel Jamu, of ICLARM-Malawi,and Dr. Jeremy Likongwe, of Bunda College. Jamu wasalso a CRSP participant from 1995 to 1998, workingwith Dr. Raul Piedrahita as a Research Assistant onthe Aquaculture Systems Modeling Research project atUniversity of California, Davis.

2-week short courses in pond construction and fish culturebasics were completed during the last eight months, andadditional training sessions are slated for July andNovember of this year.

Perhaps more important than these formal trainingefforts has been Veverica’s mentoring of pond crews,computer and lab technicians, and the many studentswho have come to Sagana to undertake research projectsas part of undergraduate or graduate programs.Approximately 15 students have worked on such projectsat Sagana during these three years; 12 of them receivedCRSP support in the form of small monthly stipends, andseven of them were conducting research as part of an M.S.program at a Kenyan University. Students have come toSagana from Moi University, the University of Nairobi,Kenyatta University, and Mombasa Polytechnic. For thosewho continue on in aquaculture, the practical experiencegained by working at Sagana with real ponds, real fish,and real fish culture problems has probably been a farmore useful learning experience than was their formalcoursework.

Current Activities

On-farm trials for Central Province were begun in Januaryof this year. Approximately 30 farmers are using at least60 ponds and rice paddies for these trials, which willcontinue through about November, at which time fish willbe harvested and the results evaluated. On-farm trials forwestern Kenya (Western and Nyanza provinces) willbegin in July and continue on through March 2001. It isexpected that approximately 25 farmers will participate inthose trials, using about 50 ponds.

A series of training sessions for Kenyan FisheriesOfficers was begun in December 1999 and will continuethrough 2000. Training sessions involve 20 officersand last for two weeks each, covering the basics ofpond construction and pond management. Threesessions have already been conducted, and two additionaltraining sessions are scheduled during the remainder ofthe year. In addition, field days in which more than 70farmers participated were held in 1999 and up to 100additional farmers will participate in field days duringthe year 2000.

CRSP investigations conducted at Sagana Fish Farm

Dates Experiment

Dec 97–Mar 98 Relative Contribution of Supplemental Feed andInorganic Fertilizers in Semi-Intensive TilapiaProduction

Apr 98–Oct 98 Optimization of Nitrogen Fertilization Rate inFreshwater Tilapia Production Ponds—Cool Season

Nov 98–Mar 99 Optimization of Nitrogen Fertilization Rate inFreshwater Tilapia Production Ponds—WarmSeason

Mar 99–Feb 00 Use of Pond Effluents for Irrigation in an IntegratedCrop/Aquaculture System

Nov 99–May 00 Fish Yields and Economic Benefits of Tilapia/ClariasPolyculture in Fertilized Ponds Receiving PelletedCommercial Feeds or Agricultural By-Products

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School groups of all ages frequently visit Sagana Fish Farm. Here, secondaryschool students listen as station personnel describe daily operations at the farm.

Aquanews ~ Summer 2000

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RELATIVE CONTRIBUTION OF RICE BRAN AND INORGANIC FERTILISERS IN SEMI-INTENSIVE TILAPIA

(OREOCHROMIS NILOTICUS) AND CATFISH (CLARIAS GARIEPINUS) POLYCULTURE IN KENYA

(Abstract of Wilson Maina Gichuri’s M.Sc. thesis)

Aquaculture development in Kenya has been hampered by lack of appropriate feeds. Available chemical fertilisers can enhancenatural food production and thus indirectly provide protein to complement energy-rich rice bran. Consequently, a 20-weekexperiment was conducted at Sagana Fish Farm, Kenya to realise least-cost combinations of rice bran and fertiliser. Twelve 800-m2 ponds were stocked with juvenile (32g) Oreochromis niloticus at 2m-2 and Clarias gariepinus fingerlings (4.6g) at 0.2m-2. Fourtreatments were applied in triplicates as follows: 1. Urea and DAP to provide 16KgNha-1week-1 and 4KgPha-1week-1; 2. Ureaand DAP applied to give 8KgNha-1week-1 and 2KgPha-1week-1, plus rice bran fed at 60Kgha-1day-1; 3. Rice bran fed at120Kgha-1day-1; 4. Rice bran as in treatment 3 and fertiliser as in treatment 2. Dissolved oxygen, temperature and pH weremeasured weekly in the morning and the afternoon while total alkalinity and total ammonia nitrogen were measuredfortnightly. Ponds were sampled monthly to measure fish growth, and drained completely after 20 weeks. At harvest, averageweight of tilapia was 89, 106, 106 and 131g while that of Clarias was 110, 217, 236 and 295g for treatments 1 through 4respectively. Specific growth rate (SGR%d-1) for tilapia was 0.6, 0.8, 1.0 and 1.0 while that for Clarias was 2.26, 2.69, 2.72and 2.90 for treatments 1 through 4 respectively. Combined Net fish yield (NFY Kgha-1) was 1,127, 1,582, 1,607 and 2,098for treatments 1 through 4 respectively. The tilapia Net fish yield (NFY Kgha-1) was 894.0, 1200.5, 1241.8 and 1576.5 whilethat of Clarias was 232, 365, 382 and 522 for treatments 1 through 4 respectively. Combined Annual production(AP Kgha-1yr-1) was 2930 4113, 4179 and 5455 for treatments 1 through 4 respectively. The tilapia Annual production (APKgha-1yr-1) was 2,324.5, 3,121.1, 3,228.7 and 4,098.7 while that of Clarias was 605, 950, 993, and 1,357 for treatments 1through 4 respectively. Apparent feed conversion ratio (AFCR) was 5.3, 10.3 and 8.0 for treatments 2 through 4 respectively.Feeding efficiency (FE) was 0.19, 0.10 and 0.13 for treatment 2 through 4 respectively. The Relative Condition Factor (Kn)for tilapia was 1.03, 1.11, 1.13 and 1.15 while that for Clarias was 1.20, 1.34, 1.38 and 1.38 for treatments 1 through 4respectively. A partial economics analysis indicated a Net profit (KSh) of 18,851, 9,895, 3,299 and 7,015 for treatments 1through 4 respectively. Although treatment 4 had the highest SGR, NFY and AP and the second highest AFCR and FE,its high net expenditure was a serious setback since not many rural fish farmers can afford such an amount of recurrentcosts. Even if they could, high unit production costs could jeopardise sales. Treatment 3 had the lowest net profit and wasthus the worst treatment in terms of profit margins. This was due to high amount of rice bran inputs. Treatment 2 hadthe third highest SGR, NFY, AP and AFCR and the second highest Net profit. It had the highest FE while its figures forSGR, NFY and AP compare favourably and closely with those of treatment 3. Probable reasons are that its high FE givesit a higher output (fish production). Feeding efficiency (FE) increases with better diet and we can conclude that treatment2 was the best diet. Treatment 1 had the highest Net profit but its growth rate began to level off at days 63 and 30 forboth tilapia and Clarias which means that fish in treatment 1 may not have reached market sizes of 250–300g for tilapiaand 500–1000g for Clarias. A combination of fertiliser as in treatment 1 and rice bran as in treatment 2 could possibly haveproduced better results where N and P could have been similar to those of treatment 4 but at much lower recurrent costs.

Degree Granted to Gichuri

W ilson Maina Gichuri successfully defended his M.Sc. thesis recently and received a M.Sc. from the University of Nairobi, Kenya. Gichuri, an officer with the Kenya Fisheries Department, conducted his thesis research incooperation with the CRSP Kenya Project at Sagana Fish Farm.

Significant New Developments in 2000

Several personnel changes of significance have occurredsince late 1999. The first was the retirement of formerFisheries Department Director Fred Pertet and the appoint-ment of Booker T.W. Odour, later followed by NancyGitonga as Acting Director. Gitonga has taken on her newduties with enthusiasm and has shown considerable interestin and support for the CRSP effort. Simultaneously, formerHead of Station Bethuel Omolo left Sagana to undertakegraduate studies in aquaculture and extension methodologyat Auburn University. Japhet K. Ngatuni was named thenew Head of Station in late 1999. He has also taken an activeinterest in the CRSP, as well as in improving the function and

appearance of Sagana Fish Farm. Gitonga serves as HostCountry Principal Investigator for the CRSP project, whileNgatuni is the Kenyan Research Associate.

A significant change in the way the project operates inKenya has taken place in recent months. The month ofMarch marked the end of Karen Veverica’s full-timepresence at Sagana. Near the end of the month shereturned to Auburn University to take up duties atAuburn’s Fisheries Research Unit. Veverica will continueto provide guidance to the Kenya Project, but this will beon a part-time basis, limited to periodic visits to Kenyaand participation in project planning, monitoring, andreporting activities by email and telephone contacts withother project participants.

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A uburn University graduatestudent and Kenya FisheriesOfficer Bethuel Omolo is

dedicated to improving the aquaculturesector back home. “Kenya’s aquacultureproduction has not surpassed 1,200metric tons for the past four years.Many farmers are giving up fishfarming due to frustrating harvests(tilapia, catfish, trout, common carp,etc.). Since the Fisheries Department isthe major extension agency, there is aneed for people with adequate know-ledge of aquaculture to step in andimprove this sub-sector of fisheries.”

After earning a Bachelor of Science inzoology from the University of Nairobiin 1981, Omolo became involved infisheries extension work in 1982,working with artisanal fisheries on theKenya coast for the Kenya FisheriesDepartment. In 1989 he moved to theRift Valley Province, this time workingwith tilapia and catfish farmers. In 1986Omolo earned a postgraduate diplomain fisheries biology in Norway. Still aFisheries Officer, he was transferred toSagana Fish Culture Farm in 1997 and

Kenya Fisheries Officer Mastering Aquaculture at Auburnby Kris McElwee

T his year, William Kiama J.Njaremwe registered a newbusiness—African Bulldozers:

pond construction and consultants. Heand his employees specialize in handconstruction of ponds. They can do thework for the same or less than what ittakes to hire a bulldozer for the job. Atleast on a small pond or on ponds torenovate, that is. He began working inthis field about seven years ago whenhe contracted with a Belgian project torenovate ponds at Sagana Fish Farm.He was later contracted by the CRSPto renovate ponds for research. Duringhis three years of working with CRSPresearchers, he learned some survey-ing, choice of pond dimensions, choiceand setting of inlets and drains, andmany other pond construction tech-niques. One could say that he and hiscrew are the only specialists in pondconstruction in the whole of Kenya.

Kiama’s group does all earth cuttingand moving by hand; even wheel-barrows are a rarity. However, as pondsize approaches 4,000 m2 or if soil hasto be moved long distances, somemachinery will be used. For example,an ox cart was used to ferry soil fromabout 300 meters to the levee construc-tion site for ponds E12 through E15 at

Sagana. Kiama’s crew can cut a leveeat a consistent 1:2 slope and they canfollow pegs and line to make a pondbottom slope at any degree desired.They are accurate to about 5 milli-meters. They have developed theirown technique of compacting soil thathas impressed many a visitor.

Kiama’s secret comes from realiz-ing the potential of each worker. Forexample, he has workers who arevery good at fine work such as slopecutting but who may have troublekeeping up with the others when itcomes to actual cubic meters exca-vated. He also has people whosestrong point is non-stop digging, sothey are given the tasks of diggingout trenches for drain pipes, butthey are not involved in the finalstages of pond bottom digging orlevee sloping. One of the frequentlyrepeated observations of thegovernment personnel, students,and visitors is that Kiama’s crew

seems to enjoy their workimmensely.

In 1998, Kiama was elected to thetown council of Sagana. He wassubsequently elected as chair of the towncouncil. This was due to his ability tofind employment for his constituents.He is also a thoughtful leader and hasambitious plans for his constituents.Although he stepped down as towncouncil chairman to set an example ofvoluntarily handing over power, hecontinues to be a major player in thedevelopment of his community.

His dream? To attend the pondconstruction course at Auburn Univer-sity. Perhaps he could even teach partof it. Kiama, his foremen, and pondmanagers have become some of thebest extensionists in the area.

For my part, one thing is certain—we could really use his crew torenovate at least 100 of our researchponds here at the Fisheries ResearchStation at Auburn.

served as station manager. The CRSPKenya Project is based at Sagana, whereOmolo met and worked with AuburnUniversity CRSP researcher KarenVeverica.

It was the Kenya Project that firstbrought Omolo to Auburn. He wasinvited to attend a study tour forCRSP host country research associatesin late 1997 that included a visit toAuburn. Omolo was “generallyimpressed by the ongoing fisheriesresearch and the linkage theUniversity has with fish farmers herein Alabama.” He returned to Auburnin 1999 to begin work on a Master ofAquaculture degree with fundingfrom the CRSP Kenya Project. TomPopma, a principal investigator on theKenya Project and Omolo’s majorprofessor, is supervising his work on aresearch project to investigate feedconversion ratios in channel catfish.

Asked about the applicability of hisassociation with the CRSP to hisaquaculture interests, Omoloexplained: “Since 1998 I have been

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Kiama’s staff on the D and E lineof ponds at Sagana.

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Excavation Enterprise Emergesby Karen Veverica

Aquanews ~ Summer 2000

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active in fish farming extension. I haveseen many farmers put so much effortbut not realize muchin terms of fishharvests. I personallyenjoy working withfish and farmers, andmy wish is to see thefish farming sub-sector develop inKenya. There havebeen success storiesin horticulture and Ifeel the same canhappen with fishfarming. Kenyans arevery sensitive to whatcan provide anincome, and thereforeif the technicalities offish farming areovercome, the private sector willdefinitely take up this economicactivity.”

Omolo feels that the results of CRSPresearch can benefit the citizens ofKenya by identifying problems inaquaculture at all levels from small-scale to commercial, preventingduplication of research by sharing

experiences learnedelsewhere, conductingrelevant research, anddisseminating theinformation to thosewho need it.

He also sees apotential benefit in“improved coordinationbetween differentfisheries institutions inKenya and East Africaas a whole. This hasbeen a big challenge asdifferent institutionshave disparateapproaches to fisheriesresearch and

management, but the CRSP hasattempted in a subtle manner toimprove information exchange

between the Fisheries Department,fisheries research institutions, anduniversities. Attachment [internship]of students from Moi University,Kenyatta University, and University ofNairobi at Sagana is one goodexample of CRSP involvement ininformation transfer.”

Omolo will continue as an employeeof the Fisheries Department when hereturns to Kenya, where his role willbe to serve as the link betweenresearch information and farmers. Heis optimistic that he will be able toapply what he learns in his graduatework: “I feel that by the end of mystay at Auburn, I will be able to assistnew and ongoing tilapia/catfishfarmers if they need assistance fromthe Department. Before my experiencewith the CRSP, I never believed thattilapia could be grown commercially,but through the extensive farm visitsand literature as well as personalinteraction with tilapia farmers in theUSA, I can see its potential, especiallyin the warmer tropical countries.”

Kenya Fisheries Officer…from p. 4

A s first reported in the Fall 1999issue of Aquanews, Upton Hatchis Project Leader for “Rapid

economic evaluation tools,” a NinthWork Plan Marketing and EconomicAnalysis study. This project is Hatch’sfirst as CRSP Project Leader, but he wasa co-Principal Investigator on an EighthWork Plan Adoption/Diffusion studyentitled “The influence of fish culturetechnology, extension methodology,and socioeconomics on success of fishculture on limited-resource farms.”

The economics of aquaculture hasbeen a focus of Hatch’s research sincehe arrived at Auburn University in1982. His current project will use fishproduction data collected by the CRSPin Honduras for the past ten years,along with local input and fish prices todevelop tools to enable a rapiddetermination of whether a particulartilapia production strategy is likely tobe profitable, easy to implement, andassociated with acceptable levels of risk.

According to Hatch, the rapideconomic evaluation tools are

intended to give extension agents andresearchers an idea of the economicincentives associated with a particularproduction practice. For example, thetools might show that a particulartreatment could involve prohibitivelabor costs or require nutrients that arenot readily available or of a qualitythat doesn’t meet research standards.

According to Hatch, “throughinteractive use of the tool, it is hopedthat the researcher can devise researchthat better responds to actual growingconditions and has some greaterlikelihood of being used.”

In addition to his Ninth Work PlanCRSP work, Hatch has recently beenon a sabbatical with NASA focusingon the use of remote sensing technol-ogy in agriculture, which mightsomeday prove useful in monitoringpond quality and fish biomass.

Hatch believes that the economics ofaquaculture is a very important part ofPD/A CRSP research efforts. As hiscurrent project illustrates, Hatch feelsthat a great potential now exists to

PD/A CRSP Profile—Upton Hatchby Matt Niles

emphasize the economic implicationsof CRSP research by utilizing thegroundwork laid by past CRSPresearchers.

Hatch also believes strongly ininterdisciplinary research andextension: “It’s more difficult, but it’salmost always the case that real-worldproblems know no disciplinaryboundaries. I’ve always felt that itwould be useful to have at least acouple of the treatments thatresearchers use in their experimentsapproximate commercial or indigen-ous practices. This way you can lookat the gap between what researchersfeel is the best way to culture a species[and] the way many producers areactually doing it. Why do they stock,feed, aerate, exchange differently thanpure research might suggest?” Hatchsuggests that such research designmight also help extension workerscome up with ways to encouragefarmers to adopt more productivestrategies, even if their practices arestill far from “optimal.”

Auburn University graduate student andKenya Fisheries Officer Bethuel Omolo

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O regon State University (OSU)graduate student John Hayeshas been conducting research,

wielding web work, and going aboutgeneral exploration in his short timehere in the Pacific Northwest.

Hayes is currently working on CRSPreproduction control research at OSUsFisheries and Wildlife Department, on aquestion of Nile tilapia sex determina-tion. This work is the heart of Hayes’thesis project and serves as one of themany requirements towards earning amaster of science degree. He is workingon a method of controlling reproduc-tion through the creation of all-malepopulations. Past researchers havecreated such populations using variousmethods, including manual separation,hybridization through interspeciescrosses, and steroid introduction.

An additional method is to manipul-ate water temperature and pH. Pastresearch on various cichlid species hasshown that high temperature and lowpH often lead to male-biasedpopulations. “Nobody has done thiswith Nile tilapia yet,” said Hayes.“Based on ecological and physiologicalsimilarities, we think that temperatureand pH could have the same effect onNile tilapia.” Hayes will experimentwith temperatures between 28 and42°C, and with pH levels as low as 3.5.Based on a window previously identi-fied by CRSP researcher MartinFitzpatrick, Hayes will apply a 3-hourtemperature and pH treatment twice,once at 11 days post-fertilization andagain at 13 days post-fertilization.

Graduate Student Profile: John Hayesby Anu Gupta

Hayes is interested in not only howtemperature and pH influence sexdetermination, but also why suchenvironmental factors have aninfluence at all. “What is the adaptiveadvantage of having all-male popula-tions at high temperatures?” he asked.“Such a question addresses evolution-ary biology.”

The ecologically friendly nature ofthis project appealed to Hayes: “I wasdrawn to Marty’s work here becausehe was getting away from steroids andlooking at environmentally respon-sible techniques.” Hayes’s interest inaquaculture arose out of a long-standing love affair with the ocean;“I’ve always had a fascination withmarine life. But at the same time Iwanted to do something practical. Iwanted to address a real-worldproblem faced by natural resourcemanagers, like the depletion of wildfisheries.”

Prior to working on his currentproject, Hayes worked at the National

Publication Announcement

Proceedings of the First International Symposium on CageAquaculture in Asia, 2000, 312 pp.Editors: I Chiu Liao (President, Asian Fisheries Society), andC. Kwei Lin (President, Southeast Asian Chapter of the WorldAquaculture Society)

I t is well recognized that aquaculture is playing an increasingly important role in world fisheries productionto meet the rapidly rising demand for fisheries products.

The most significant contribution from aquaculture occurs inAsia, which produces 90% of the total world aquaculture

Oceanic and Atmospheric Admini-stration (NOAA) in Washington, D.C.,for four years, serving as a GeographicInformation System (GIS) technician,a website developer, and a StatisticalAnalysis System (SAS) programmer.Prior to that, Hayes attended theUniversity of Maryland, graduatingin 1993 with a B.S. in marine biology.

Aquaculture first interested Hayeswhen he was working at NOAA. Hewas especially interested in workingwith tilapia, a species showing highgrowth potential and fewerlimitations than anadromous fish.Hayes was also interested inexploring the West Coast, and thusin September 1999 he started atOSU. While here, Hayes has put hisweb skills to use at the CRSPInformation Management andNetworking Component (IMNC) inCorvallis, Oregon. On July 1, CRSPsupport of Hayes’ graduate researchassistantship moved from the IMNCto Fisheries and Wildlife; he willthen focus full-time on research.

Hayes has recently becomeinterested in the business side ofaquaculture. He is contemplating theidea of getting an MBA. “I would liketo get a hard science degree that I canapply in a management setting.”

When he is not working, Hayes findstime to explore the Pacific Northwest.“On the East Coast the outdoors are notas accessible. Here you can find trailsand mountains and forests close tocampus. I have definitely been takingadvantage of that.”

production. Although cage aquaculture has existed forcenturies, only in recent years has it been widely practicedand recognized for its potential to produce mass quantities ofa large variety of aquatic animals in diverse environmentssuch as ponds, rivers, lakes, reservoirs, estuaries, and theopen sea.

The First International Symposium on Cage Aquaculture inAsia, held 2–6 November 1999 in Tungkang, Taiwan,provided an opportunity for the first time to the aquaculturecommunity in Asia and outside of the region to meet anddiscuss current developments in cage aquaculture.

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CRSP graduate student John Hayes

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Aquanews ~ Summer 2000

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An economic analysis of shrimp aquaculture in Honduraswas conducted through the development of two separatemodels. The first model measured the effect of variabilityof production factors on the profitability of shrimpoperations under different farm scenarios for a givenproduction year (1997). Results of this model pointedout a major potential for profit developed by farmsemploying an alternative scheme of semi-intensivetechnologies (AST) characterized by higher feeding ratesand water exchange rates. However, data limitationsdid not allow extrapolation of these results to otherproduction years. To overcome this limitation, a newdatabase was compiled to develop a one-year linearprogramming (LP) optimization model for each farm-size scenario previously identified. Results indicatedthat maximization of farm income is achieved byselecting intermediate stocking densities, long grow-outperiods, and conservative water exchange rates. Inaddition, farmers should take full advantage of thesuperior growth rates characteristic of stocking monthssuch as May and June by concentrating use of resourcesduring this period of the year. The LP models alsoindicated that, under optimal management conditions,shrimp farms in Honduras have the capacity of producingmore than 1,000 kg shrimp tails/ha/year, which impliesthat superior yields reported by the AST farms arewithin the reach of the farming capabilities of mostshrimp farms in the country. Target MOTAD riskprogramming models were then developed for eachfarm scenario to assess the risk inherent to the LPsolutions and to identify alternative production plans.However, the LP models indicated that shrimp farmshave such a tremendous potential to generate incomeover critical target income levels that little risk isassociated with the formulated optimal plans of activities.Additional simulations were conducted to examine theeffects of changing conditions on the profit levels andmanagement strategies selected by the LP models. Ingeneral, results of these simulations showed that shrimpfarms in Honduras possess the potential to maintainacceptable profit levels under a variety of managementsituations.

The variability in the factors affecting sex ratio of Oreochromisniloticus was studied using pair spawns from the Egypt,Ghana, and Ivory Coast strains during June – October,1997 and 1998. Sex ratios from 129 progeny groups weredetermined by microscopic inspections of the gonads. Ofthe 12, 450 progeny sexed, 54.14% were males, whichdiffered significantly from a 1:1 sex ratio (P < 0.001). Eachstrain had at least 42% of their spawns differ from a 1:1 sexratio (P < 0.05). Logistic regression demonstrated the percentageof males produced by the Ghana strain to differ significantlyfrom that of the Egypt or Ivory Coast strain (P = 0.02). Sexratios from the 129 progeny groups produced a normaldistribution (P > 0.45), but did not reflect a binomialdistribution (P < 0.01), as would be predicted by a simplemonofactorial sex determination process. Therefore, otherfactors must account for the variation observed in sex ratios.Single spawn sex ratios ranged widely from 16% to 100%males. Chi-square tests revealed weak correlations betweenstrain and progeny gender, individual parent and progenygender, as well as, male-female parent combinations andprogeny gender. Sixty-five percent (11/17) of the repeatspawns by the same pairings produced sex ratios that extendedbeyond a range of 10%. The continuous range of sex ratioswithin the normal distribution suggested the presence ofseveral minor sex-modifying factors in Oreochromis niloticus.

Diego Valderrama successfully defended his M.S. thesison 1 May 2000 at University of Arkansas at Pine Bluff.He is continuing to work as a Research Assistant withCarole Engle, CRSP Marketing and Economic Analysisresearcher, who also served as his thesis advisor.

C ongratulations to Lee Warrington, who successfullydefended his M.S. thesis on 11 December 1999 atAuburn University under the direction of CRSP

Reproduction Control researcher Ron Phelps.

Valderrama, Warrington Successfully Defend M.S. Theses

ECONOMIC ANALYSIS OF SHRIMP FARMING INHONDURAS

(abstract of Diego Valderrama’s M.S. thesis)

SEX RATIO VARIATION AND SEX DETERMINING

MECHANISMS IN OREOCHROMIS NILOTICUS

(abstract of Lee Warrington’s M.S. thesis)

The proceedings comprise abstracts and full papers ondiverse topics that review the status of cage culture in Asiancountries, identify problems and opportunities, assess researchneeds, and discuss sustainable culture technologies and theirmanagement. Papers by CRSP researchers Kwei Lin and YangYi are included (see Notices of Publication, p. 13). This publica-tion provides a wealth of information useful for fish culturists,scientists, traders, and planners in private and public institutions.

A list of the papers presented and their authors can bedownloaded from the Internet at <www.cgiar.org/iclarm/afs/pubs97~1.htm>. For information on ordering a copy of thispublication, email <WASMAS@aol.com> or write to:

World Aquaculture Society143 J. M. Parker ColiseumLouisiana State UniversityBaton Rouge, LA 70803 USA

Publication Announcement…from p. 6

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Felicitations to Douglas Ernst, who successfullydefended his Ph.D. dissertation on 17 April 2000 atOregon State University. Ernst worked under the

advisement of CRSP researcher John Bolte.

AQUAFARM©: SIMULATION AND DECISION-SUPPORT

SOFTWARE FOR AQUACULTURE FACILITY DESIGN AND

MANAGEMENT PLANNING

(abstract of Douglas Ernst’s Ph.D. dissertation)

A simulation and decision-support software product foraquaculture facility design and management planning is described(AquaFarm, Oregon State University©), including comprehensivedocumentation and applications to practical problems. AquaFarmprovides (1) simulation of physical, chemical, and biologicalunit processes, (2) simulation of facility and fish culturemanagement, (3) compilation of facility resource and enterprisebudgets, and (4) a graphical user interface and data managementcapabilities. These analytical tools are combined into an interactivedecision support system for the analysis and development offacility design specifications and management strategies. Intendeduser groups include aquaculture research, engineering, education,and production. As guided by the user, aquaculture facilitiescan be of any type, configuration, and management objective,for purposes of broodfish maturation, egg incubation, and/orgrowout of finfish or crustaceans in cage, single pass, serialreuse, water recirculation, or solar-algae pond systems. User-accessible specifications include (1) site climate and watersupplies, (2) components and configurations of fish culturesystems, (3) fish and facility management strategies, (4) unitcosts for budget items, (5) production objectives (species, timeschedules, and fish numbers and weights), and (6) parametersof unit-process and fish performance models. Based on thesespecifications, aquaculture facilities are simulated, resourcerequirements are compiled, and operation schedules aredetermined so that production objectives are achieved. Facilityperformance is reported to the user as management schedules,summary reports, resource and enterprise budgets, and tabularand graphical compilations of time-series data for unit process,fish, and water quality variables. If unsatisfactory resourcerequirements or unattainable production objectives are found,procedures of iterative design and management refinement aresupported. To provide this analytical capacity, a wide range ofexisting and newly developed quantitative methods and modelsare assembled and synthesized into an integrated analyticalframework, including aquatic chemistry, aquatic biology, fishbiology, aquacultural engineering, and simulation techniques.Unit-process and system-level validation exercises are demonstratedfor a wide range of aquaculture facilities in which (1) facilitiesare constructed according to reported studies, (2) simulationtrials are accomplished, and (3) good agreement betweenpredicted performance and empirical observations is demonstrated,given that sufficient specification of site-specific variables isprovided.

Ernst Dissertation Describes AquaFarm©Kudos

J ames Diana—US Regional Coordinator for theThailand Project, co-chair of the PD/A CRSPTechnical Committee, and CRSP participantsince 1983—was named Associate Dean of the

School of Natural Resources and the Environment atThe University of Michigan. After receiving adoctorate in zoology at the University of Alberta,Canada, Diana joined the UM faculty in 1979. Inaddition to his CRSP involvement, Diana works onfish energetics, studying the behavioral ecology ofnorthern pike and other temperate fishes. He is alsointerested in the conservation of aquatic naturalresources, through work on endangered fish speciesand through the development of ecologicallyresponsible aquaculture practices.

W ilfrido Contreras-Sánchez was awarded the Savery Outstanding Graduate StudentAward by the Oregon State University College

of Agricultural Sciences. The Savery award, sponsored bythe Agricultural Research Foundation, recognizesgraduate students whose research benefits Oregon

agriculture and naturalresources. Contreras-Sánchez isa faculty member atUniversidad Juárez Autónomade Tabasco (UJAT) and adoctoral student at OSU,working on CRSPReproduction ControlResearch. The award waspresented at the GreatAchievements of StudentsCelebration held 18 May 2000on the OSU campus.

In addition to completing amaster’s degree at the University of Arkansas at PineBluff (see p. 7), Diego Valderramawon two awards recently. Hereceived a plaque and a check forone of the best student abstractssubmitted to Aquaculture 2000from the US Aquaculture Societyfor his paper “Risk Analysis ofShrimp Farming in Honduras.”He was also awarded BestGraduate Student Paper in theSchool of Agriculture, Fisheries,and Human Sciences at the 2000UAPB Annual Research Forum forhis paper entitled “A RiskProgramming Model for ShrimpFarming in Honduras.” The forum was held 15–16 March2000 on the UAPB campus.

Award Winning Graduate Students

Diego Valderrama,recipient of two awardsand a master’s degree.

Savery Award winnerWilfrido Contreras-Sánchez

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I n late June two members of the PD/A CRSP External EvaluationPanel (EEP), Kevan Main and

David Cummins, undertook the firstof three site visits to CRSP researchsites. The two visited the AsianInstitute of Technology (AIT), locatedin Pathumthani, Thailand, where theyvisited with CRSP researchers,students, and extension agentsassociated with AITs aquacultureprogram. They also visited UdornThani, where they met with farmersand researchers who are part of acollaborative outreach programbetween the CRSP and the Thai RoyalDepartment of Fisheries. ParticipatingEEP members Main and Cumminswere joined by PD/A CRSP DirectorHillary Egna and PD/A CRSP USAIDProject Officer Harry Rea.

This site visit is part of the five-yearin-depth review process required byBIFAD (Board of International Foodand Agriculture Development)guidelines. The EEP will also partici-pate in site visits to the Instituto deInvestigaciones de la AmazoniaPeruana and the UniversidadNacional de la Amazonia Peruana inPeru in September 2000. In November,the EEP is scheduled to visit insti-tutions in Kenya, including SaganaFish Farm, Moi University, and theUniversity of Nairobi.

The review process will continuethrough the program annual meeting inOrlando, Florida, in January 2001.

K evan L. Main currently serves as the Deputy Director of the Harbor Branch Oceano-graphic Institution’s AquacultureDivision, in Fort Pierce, Florida.Main joined Harbor Branch in 1997;for more than ten years before that,she served as the Director of theUSDAs Center for Tropical andSubtropical Aquaculture, located inWaimanalo, Hawaii. She alsodirected its Oceanic Institute’s AsianInterchange Program. Main receivedher Ph.D. from Florida StateUniversity, where she focused onseagrass meadows. Main is amember of the World AquacultureSociety’s Board of Directors andserves as the chairman of theAffiliations Committee for theSociety.

Christine Crawford has worked inthe marine aquaculture field for overtwenty years, primarily in finfish andshellfish aquaculture research, and inaquaculture extension. She is currentlythe Marine Environment SectionLeader for the Marine ResearchLaboratories, Tasmanian Aquacultureand Fisheries Institute, University ofTasmania, located in Taroona,Tasmania. Recently, Crawford hasbegun investigating the effects ofaquaculture on the marineenvironment. Prior to joining theUniversity ofTasmania,Crawford servedas a consultantand lectureraround theworld. She holdsa Ph.D. in marineecology from theUniversity ofTasmania,Australia.

DavidCummins hasbeen closelyallied with CRSPresearch for overtwenty years,having served asProgram Directorand Associate

EEP visits Thailand

Two members of the External Evaluation Panel were among those who learnedabout cage culture in aquaculture ponds during a field visit in Thailand.

Meet the External Evaluation Panel

Director of the Peanut CRSP, admin-istered through the University ofGeorgia. As Director, Cumminsorganized research programs betweenthe US and host countries andimplemented research. Cumminsholds a Ph.D. in Agronomy from theUniversity of Georgia. He has traveledthroughout the world, and from 1986to 1988 served as the AgriculturalResearch Advisor for USAID inManila, the Philippines. In 1996Cummins was named recipient of theD.W. Brooks Award for Excellence inInternational Agriculture.

Edna McBreen has over twentyyears of experience with domesticand international education. She iscurrently Associate Vice Chancellorfor the Institute of Agriculture andNatural Resources, University ofNebraska, Lincoln, Nebraska.Previously, McBreen was AssociateDean and Director of theCooperative Extension of theCollege of Agriculture, University ofWyoming in Laramie, Wyoming. Shereceived her Ph.D. from CornellUniversity in Ithaca, New York,where her dissertation focused onthe interface between family lawand home economics. McBreen hasserved on the EEP of the Bean/Cowpea CRSP and the GlobalLivestock CRSP.

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IIFET 2000 Conference

T he tenth biennial conference of the InternationalInstitute of Fisheries Economics and Trade (IIFET2000) took place 10–13 July 2000 at Oregon State

University in Corvallis, Oregon, USA. The conferenceincluded presentations by historians, legal scholars,industry spokespeople, policy-makers, biologists,nutritionists, and social and behavioral scientists.

The theme of the conference, Microbehavior andMacroresults, reflected the relationship of individualbehavior to the aggregate consequences of that behavior.Conference presentations covered a broad range of topicsunder this theme, including fishery biology and the social

sciences; aquaculture: past, present, andfuture; fisheries in economic

development; issues in internationaltrade; consumer demand for seafood;

seafood market behavior; and seafoodconsumption and human health. (Visit

the IIFET 2000 website at <osu.orst.edu/dept/IIFET/2000/> for a complete list of

presentations and abstracts.) As with past IIFETconferences, IIFET 2000 provided both formal andinformal opportunities for interaction among theparticipants. (More detailed conference coverage willfollow in the Fall 2000 issue of Aquanews as this issuewent to press during the final days of the conference.)

The PD/A CRSP co-sponsored the event and providedthe following researchers from PD/A CRSP host countriesthe opportunity to attend and present:Eunice Pérez Sánchez, Institute of Aquaculture,University of Stirling, UK

Aquaculture Impacts in the Socio-economics of the CoastalCommunities of Tabasco, Mexico (online abstract: <osu.orst.edu/dept/IIFET/2000/abstracts/sanchez.html>)

Ruben Sevilleja, Freshwater Aquaculture Center, CentralLuzon State University, Philippines

Adoption and Economics of Tilapia Farming Technology inthe Philippines (online abstract: <osu.orst.edu/dept/IIFET/2000/abstracts/sevilleja.html>)

Ruamporn Sirirattrakul, National Statistical Office,Thailand

Dramatic Development of Shrimp Aquaculture in Thailand(based on the 1985 and 1995 Thai Marine Fishery Census)(online abstract: <osu.orst.edu/dept/IIFET/2000/abstracts/sirirattrakul.html>)

Mathias Wafula, Fisheries Department, KenyaSocio-economic Impact of Aquaculture Support Programmeson the Communities in the Lake Victoria Basin of Kenya(online abstract: <osu.orst.edu/dept/IIFET/2000/abstracts/wafula.html>)

Congratulations to conference participants andorganizers for making IIFET 2000 a success.

CRSP Co-Sponsors ISTA V

T he PD/A CRSP is pleased to be a co-sponsor of the Fifth International Symposium on Tilapia Aquaculture(ISTA V), which will take place 3-7 September 2000 at the Sofitel Rio Palace, Rio de Janeiro, Brazil. ISTA V willfocus on the rapid advances in large-scale commercial farming and the development of international markets. The

symposium will include a trade show, which will provide a forum for industry suppliers, seafood marketers, and theaquaculture press to meet directly with researchers and producers. Field trips are being organized to nearby aquaculturesites. Additional information about ISTA V is available on the Internet at <ag.arizona.edu/azaqua/ista/announce.htm>.

CRSP Sponsorship

The PD/A CRSP is providing an opportunity for three scholars with ties to existing and previous PD/A CRSP hostcountries (Malawi, Philippines, and Thailand) to attend and present papers. The scholars chosen for sponsorship wereselected by ISTA V conference organizers. The three scholars are listed below, along with the papers they will present:

Remedios B. Bolivar, Freshwater Aquaculture Center, Central Luzon State University, Philippines1. Response to Selection for Body Weight of Nile Tilapia (Oreochromis niloticus) in Different CultureEnvironments2. Timing of the Onset of Supplemental Feeding of Nile Tilapia (Oreochromis niloticus) in Ponds

Yang Yi, Aquaculture and Aquatic Resources Management, Asian Institute of Technology, ThailandAnalyses of Various Inputs for Pond Culture of Nile Tilapia (Oreochromis niloticus): Profitability andPotential Environmental Impacts

Daniel Jamu, International Center for Living Aquatic Resources Management, Zomba, MalawiA Pilot Study on the Spatial and Temporal Soil Moisture Distribution in Integrated Crop-Fish-Wetland andCrop-Wetland Agrosystem in Zomba-East, Malawi

Aquanews ~ Summer 2000

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Aquaculture Update from Malaysiaby TJ Tan

Kuala Lumpur

T he growing demand for fish and the heavy expenseinvolved in developing deep-sea fishing have generatedincreasing interest in aquaculture in Malaysia.

The Malaysian government expects demand for fish forhuman consumption to increase from 1.2 million tonnes peryear now to 1.9 by 2010, as the population expands from 22million to almost 29 million. Much of the increase is expectedto come from aquaculture. The government’s target foraquaculture is 600,000 tonnes per year, which entails a 460%increase from 133,000 tonnes at present.

Currently, farming is focused on cockles, shrimp, tilapia,carp, and catfish. Efforts are being made to farm snapper,grouper, and seabass in offshore cages and to attract bigbusiness to the sector. There are also plans to expand seaweedculture.

The Malaysian agriculture ministry has teamed up with theprivate-sector companies, public-listed ConsolidatedPlantation, Aquacon, and Langkawi Marine Farm, in a projectto farm snapper and grouper in cages off the island ofLangkawi in the Straits of Malacca.

The farms use adapted Norwegian technology and thecompanies provide the cash and manpower, while the ministrysupplies fingerlings and the expertise.

Public-listed Golden Hope Plantations has embarked on aproject to farm grouper in cages off the island of Penangfurther south, also using Norwegian technology. Shippingcompany Halim Maznim is farming seabass and grouper incages located about a kilometer offshore in the Straits ofMalacca.

In the states of Malacca and Johor in southern peninsularMalaysia, fishermen will take part in an offshore fish breedingproject costing US$13 million. The Malacca government and aprivate-sector company, Muara Aquaculture Park, are fundingthe project. The project involves breeding of fish and bivalves.Some 50,000 square metres off Nangka Island has beenearmarked for offshore cage culture.

Under the first phase, a fish hatchery will be built to producesome 24 million fish per year of local species such as kerapu,siakap, and jenahak. Under the second phase, 16 fish cages willbe placed off the island, and each cage is expected to produce upto 2,000 tonnes of marine fish.

The East Malaysian state of Sabah is setting up seaweednurseries on Balambangan Island off the northern coast toexpand seaweed farming in the state. Large-scale nurserieswill also be set up on Omadai Island, off Semporna in thesouth where local entrepreneurs have developed 200 hectaresof seaweed farms.

Fishellaneous ItemsThis month’s Fishellaneous Items section contains two articles writtenfor Aquanews covering non-CRSP aquaculture activities. The Peruarticle was donated by CRSP participant Konrad Dabrowski, while theupdate on Malaysia was donated by Aquanews subscriber TJ Tan.

The “El Ingenio” trout farm of Junin Province Directorate ofFisheries with expanded facilities for visitors and educational

purposes.… continued on p. 12

Rainbow Trout Culture in thePeruvian Highlandsby Konrad Dabrowski

A lthough rainbow trout culture hasbeen practiced in the PeruvianHighlands for over 70 years, recent

interest in expanding this activity has beensparked by the success of fish culturists inother Central and South Americancountries. The initiative is also coming fromresearchers in the Department of Nutritionat the National University of Agriculture LaMolina in Lima, Peru. Dr. Carlos Gomez,chair of this department, organized twoworkshops in March on nutrition ofrainbow trout for industry representatives,state fisheries biologists, and privatefarmers from local cooperatives. KonradDabrowski, PD/A CRSP researcher on thePeru Project from Ohio State University,spoke at the workshops on nutrient require-ments, diet formulation, and general aspectsof trout culture. Dabrowski also visited twoof what may be the highest elevation troutfarms in the world. The farm at Patchakayo,at 11,216 feet above sea level, is operated bya local cooperative and annually produces100 tons of trout for export and localmarkets. The facility in Huancayo Province,operated by the Regional Directorate ofFisheries, provides stocking material forlocal farmers and serves as a publiceducation center. These Andean troutfacilities offer unique opportunities forexperimental and applied research on theeffect of high altitudes on fish performance.Abundant, high quality water available inthe highlands and an unlimited supply offish meal from the Peruvian sea fisherymake this region favorable for aquaculturedevelopment.

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Notices of PublicationThese Notices of Publication announce recently published work carried out under PD/A CRSP sponsorship. Toreceive a full copy of a report, please contact the author(s) directly unless it is otherwise noted.

CRSP Research Report 00-146

EFFECTS OF FEEDING PELLETED VERSUS NON-PELLETEDDEFATTED RICE BRAN ON NILE TILAPIA OREOCHROMISNILOTICUS PRODUCTION AND WATER QUALITY IN PONDS

P. Perschbacher and R. LochmannAquaculture/Fisheries CenterDepartment of Aquaculture and FisheriesUniversity of Arkansas at Pine BluffP.O. Box 4912Pine Bluff, AR 71611 USA

Effects of pelleted versus non-pelleted defatted rice branon fish production and water quality were evaluated at theAquaculture Research Station, University of Arkansas atPine Bluff. Mixed-sex Nile tilapia (Oreochromis niloticus)were stocked at 2.3/m-2 into each of six 0.04-ha earthenponds. Largemouth bass (Micropterus salmoides) wereadded at 0.17/m-2 for population control. Defatted ricebran was fed to fish at 2% body weight daily. After 169days, tilapia harvests averaged 2,924 kg/ha in pellet-fedand 3,031 kg/ha in loose bran-fed treatments (a non-significant difference). Stocked fish comprised an averageof 52% and 39%, respectively, in these treatments, andapproached a significant difference (P=0.2). Averageamounts of inorganic fertilizer required to maintainchlorophyll a levels of 100-150 mg/m-3 were significantlydifferent at 736 and 1,108 kg/ha in pelleted and loose brantreatments, respectively.

This abstract was excerpted from the original paper, whichwas published in Asian Fisheries Science, 12(1999):49–55.

CRSP Research Report 00-147

SOUND POLICIES FOR FOOD SECURITY: THE ROLE OFCULTURE AND SOCIAL ORGANIZATION

Joseph J. MolnarDept of Agricultural Economics and Rural SociologyAuburn University, AL 36849-5406 USA

Culture conditions the ability to organize and to providefood security, but social organization is the immediatesource of policies that prevent food insecurity ordetermine what happens when it does occur. Weather, war,terrorism, conflict, overpopulation, environmentaldegradation, corruption, and faulty policies have beenidentified as causes of food insecurity. Perhaps most of theblame for food insecurity should go to faulty policies orpoor implementation of sound policy. This articleidentifies reasons for both kinds of failure that are linkedto culture and social organization. The central task ofgovernment is to allow the food system to manage its ownaffairs, but policies must be ready to guide action whenmarket, crop, or policy failures create food insecurityamong those with no other means of coping withadversity.

This abstract was excerpted from the original paper, whichwas published in Review of Agricultural Economics,21(2):489–498.

Local fishermen are increasingly turning to growing thealgae as an alternative source of income, particularly as itdoes not require heavy investment.

Sabah hopes to export seaweed to the Philippines, whichhas a thriving seaweed processing industry, and toSingapore.

Researchers have developed a stratified fish rearingtechnique that they say has a capacity about ten times thatof conventional ponds. With the technique, nearly a millionfish could be cultured in a 0.5-hectare pond by stratifying

Aquaculture Update from Malaysia…from p. 11

the habitat of different fish, compared with about 100,000using conventional methods, say the researchers atTechnology Park Malaysia.

“Different fish have different feeding habits. Forexample, tilapia prefer to eat near the surface while patinand catfish like to feed at the middle and bottom levels,”TPM director Professor Ishak Ismail says.

The technique is a novel solution to the problem of landshortage faced by the aquaculture sector in peninsularMalaysia.

Aquanews ~ Summer 2000

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CRSP Research Report 00-148

INTEGRATED CAGE CULTURE IN PONDS: CONCEPTS,PRACTICE AND PERSPECTIVES

Yang Yi and C. Kwei LinAquaculture and Aquatic Resources Management ProgramAsian Institute of TechnologyP.O. Box 4, Klong Luang, Pathumthani 12120Thailand

The integrated cage culture in ponds refers to the systemin which high valued species are stocked in cages suspend-ed in ponds while filter-feeding species are stocked in openwater outside the cages. While the caged fish are fed withhigh protein diets, the open-pond fish are solely dependenton the natural foods generated from cage wastes.

The following advantages make the integrated cageculture in ponds attractive and promising:

(1) Wastes derived from high protein diets of caged fishare reused as a valuable nutrient source to generatenatural foods for open pond fish.

(2) Nutrients in wastes derived from cages arerecovered thus reducing nutrients contained ineffluents, which are usually released directly orindirectly to the surrounding environment, causingaccelerated eutrophication in those waters.

(3) It is used in polyculture ponds to confine costly highprotein diets to caged high valued species to achievehigher economic returns.

(4) It is used in sub-tropical or temperate regions, wheretropical fish species cannot overwinter, to make fulluse of growing seasons and make management suchas fish harvest easy and convenient.

(5) This system makes it possible to fatten largefingerlings with high protein diets in cages andnurse fry with natural foods derived from cageswastes in open water in a single pond, which couldallow small-scale farmers with one pond tomaximize fish production and profitability.

The integrated cage culture in ponds has been practicedin caged catfish-open pond tilapia and caged large tilapia-open pond small tilapia. Encouraging results have beenachieved from the above trials.

This abstract was excepted from the original paper,which was published in I.C. Liao and C.K. Lin (Editors),Proceedings of the First International Symposium on CageAquaculture in Asia. Asian Fisheries Society, Manila,Philippines, pp. 217–224.

CRSP Research Report 00-149

AN OVERVIEW OF FRESHWATER CAGE CULTURE INTHAILAND

C. Kwei Lin and K. KaewpaitoonAquaculture and Aquatic Resources Management ProgramAsian Institute of TechnologyP.O. Box 4, Klong Luang, Pathumthani 12120Thailand

Despite its long history and a large number of rivers andreservoirs in Thailand, cage culture contributed only 0.3%of 200,000 tons in total fish production from freshwateraquaculture. Over the last decade, the peak of annual fishproduction from freshwater cages reached 2,700 tons in1991 and declined since to a minimum of 600 tons in 1995.Although cage culture takes place in various habitats suchas river, reservoirs, irrigation canals and large ponds, itspredominant habitats are in flowing waters. Among adozen of cultured species, red snakehead (Channamicropeltes), catfish (Pangasius spp.), marble goby(Oxyeleotris marmoratus) and tilapia (Oreochromis spp.)topped the list. The production of those species fluctuateddrastically resulting mainly from deteriorating waterquality, competing for trash fish feed, changing marketvalue, and shifting culture practices. However, disease andfingerling supply caused the reduction and limitation inculture of the most valued marble goby. Recently, the cageculture of tilapia has gained great popularity in certainparts of the country. Cage culture has been a small-scale,artisanal operation with little research and technicalinnovation. Further development of cage cultures infreshwater lies on ecologically sound multiple uses ofreservoirs and flowing waters. In addition, integration ofintensive cage culture with semi-intensive species in pondsshould also be promoted.

This abstract was excerpted from the original paper, whichwas published in I.C. Liao and C.K. Lin (Editors),Proceedings of the First International Symposium on CageAquaculture in Asia. Asian Fisheries Society, Manila,Philippines, pp. 237–242.

Notices of Publication (cont.)

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Upcoming Conferences and Expositions

Date Topic/Title Event Location Contact Information

July 20–23 3rd International Conferenceon RecirculatingAquaculture

Roanoke,Virginia, USA

Dr. George Libey, Recirculating Aquaculture Conference2000, Virginia Tech, Blacksburg, VA 24061;Phone: 540-231-6805; Fax: 540-231-9293;Email: CFAST@vt.edu

July 23–26 International Congress onthe Biology of Fish

Aberdeen,Scotland

Don MacKinlay; Phone: 604-666-3520;Email: MacKinlayD@pac.dfo-mpo.gc.ca;Website: <www.fishbiologycongress.org>

July 24–July 28 4th International Conferenceon Aquaculture:Fundamental & AppliedAspects

Liege, Belgium Raymond Gilles; Email: R.Gilles@ulg.ac.be;Website: <www.ulg.ac.be/physioan/aquacult.htm>

August 20–24 130th American FisheriesSociety Annual Meeting

St. Louis,Missouri, USA

Betsy Fritz; Phone: 301-897-8616/212;Email: bfritz@fisheries.org

September 3–5 5th International Symposiumon Tilapia in Aquaculture

Rio de Janeiro,Brazil

Phone: 021-553-1107; Fax: 021-553 3487

September 28–Oct 1

2nd International Exhibitionon Fishing and Aquaculture

Athens, Greece Phone: 301-92-21-254; Fax: 301-92-21-589;Email: europart@hol.gr

September 29–October 5

International MarineBiotechnology Conference(IMBC) 2000

Townsville,Queensland,Australia

Phone: 61-7-4781-6219; Fax: 61-7-4781-5822;Email: imbc_2000@aims.gov.au

October 1–2 1st Annual Southern NewEngland & 5th Annual RhodeIsland AquacultureConference

Newport, RhodeIsland, USA

David Alves; Phone: 401-783-3370;Fax: 401-783-3767;Email: dalves@crmc.state.ri.us

October 5–7 III Simposium Internacionalde Acuicultura

Sinaloa, Mexico Phone: 52-67-172720; Fax: 52-67-146705;Email: terramar@pacificnet.com.mx

October 25–28 4th Latin AmericanAquaculture Congress &Exhibition

Atlapa, Panama Email: camaricultura@gfce.com

October 31–November 3

Third World FisheriesCongress

Beijing, China Phone: 86-10-64194233; Fax: 86-10-64194231;Email: scfish@agri.gov.cn

November 1–4 Marketing Live AquaticProducts 2000

Annapolis,Maryland, USA

Phone: 302-645-4060; Fax: 302-645-4007;Email: ewart@udel.edu

November9–12

AgAsia 2000 Bangkok,Thailand

Email: agasia@reedtradex.co.th

November14–17

FISHERY 2000 Jakarta,Indonesia

Phone: 852-2851-8603; Fax: 852-2851-8637;Email: topreput@hkabc.net

November19–22

V International Symposiumon Aquaculture Nutrition

Yucatan, Mexico Phone: 52-99-812973; Fax: 52-99-812334;Email: sinav@kin.cieamer.conacyt.mx

November 29–December 5

Expo Pesca 2000 &Acuicultura 2000

Santiago, Chile Phone: 509-838-8755; Fax: 509-838-2838;Email: sue.hill@informa.com

December 7–9 Northeast AquacultureConference and Exposition

Portland, Maine,USA

Phone: 888-454-7469

January 21–25,2001

Aquaculture 2001 Orlando, Florida,USA

WAS Conference Manager, World Aquaculture Society,21710 7th Place West, Bothell, WA 98021;Phone: 425-485-6682; Fax: 425-483-6319;Email: worldaqua@aol.com

April 26–28,2001

Acquacoltura International2001

Verona, Italy Phone: 425-485-6682; Fax: 425-483-6319;Email: worldaqua@aol.com

August 19–23,2001

131st American FisheriesSociety Annual Meeting

Phoenix,Arizona, USA

Betsy Fritz; Phone: 301-897-8616 ext. 212;Email: bfritz@fisheries.org

Aquanews ~ Summer 2000

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Workshops and Short Courses

Date Title/Topic/Site Contacts

July 25–29 Recirculating Aquaculture Systems/ACTED Aquaculture Center for Training, Education, and Demonstration(ACTED); Contact: Harbor Branch Oceanographic Institution, 5600US Hwy 1 North, Ft. Pierce, FL 34946; Phone: 800-333-4264 or561-465-2400 ext. 416; Fax: 561-466-6590;Email: acted@hboi.edu; Website:<www.aquaculture-online.org>

August 14–18 Intensive Shrimp Culture/ACTED ACTED (see above)

August 14–September 8

Advances In Tilapia Fry Production AndGrow-Out/Asian Institute of Technology,Thailand

Training and Consultancy Unit (TCU), Aquaculture and AquaticResources Management Program, Asian Institute of Technology,PO Box 4, Klong Luang, Pathumthani 12120, Thailand;Phone 66-2-524-5219; Fax: 66-2-524-5484; Email: tcuaasp@ait.ac.th;Website: <www.agri-aqua.ait.ac.th/tcu>

August 15–17 OSU Surimi Technology School/ ThaiDepartment of Fisheries, Bangkok, Thailand

Phone: 662-642-5322; Fax: 662-248-8304; Email: jae.park@orst.edu

August 21–22 Production Planning/ACTED ACTED (see above)

August 23–25 Opportunities in Aquaculture/ACTED ACTED (see above)

September 15 Backyard Aquaculture/ACTED ACTED (see above)

September19–21

Opportunities in Aquaculture/ACTED ACTED (see above)

September 22 Marine Aquarium Keeping/ACTED ACTED (see above)

October 4–6 Aquaculture Marketing Seminar 2000/Asheville, North Carolina

Aquaculture Magazine, PO Box 2329, Asheville, NC 28802;Phone: 828-254-7334; Fax: 828-253-0677;Email: seminar@aquaculturemag.comWebsite: <www.aquaculturemag.com/>

October 13 Shrimp Farming Opportunities/ACTED ACTED (see above)

October 16–20 Hard Clam Aquaculture/ACTED ACTED (see above)

October 23–27 Bivalve Hatchery Operations/ACTED ACTED (see above)

November 3 Backyard Aquaculture/ACTED ACTED (see above)

November12–15

Design and Operation of AquacultureFacilities/The Hotel Roanoke ConferenceCenter, Roanoke, Virginia, USA

Dr. Greg Boardman, Phone: 540-231-2013; Email: gboard@vt.eduWebsite: <www.conted.vt.edu/doaf.htm>

November13–17

Recirculating Aquaculture Systems/ACTED ACTED (see above)

December 6–8 Opportunities in Aquaculture/ACTED ACTED (see above)

January 24–February 18,2001

Coastal Planning and Management forAquaculture Development/Asian Instituteof Technology, Thailand

Training and Consultancy Unit (see above)

March 20–31,2001

Coastal Aquaculture Study Tour/AsianInstitute of Technology, Thailand

Training and Consultancy Unit (see above)

May 1–12,2001

Inland Aquaculture Study Tour/AsianInstitute of Technology, Thailand

Training and Consultancy Unit (see above)

Year-round Training and Research in Fisheries and StockManagement/Wageningen AgriculturalUniversity, the Netherlands

G. van Eck, Dept of Fish Culture & Fisheries, PO Box 338, 6700 AHWageningen, The Netherlands; Phone: 31-8370-8330;Fax: 31-8370-83937; Email: gerrie.van.eck@alg.venv.wau.nl

Year-round Tropical Aquaculture Advanced Training ina Third World Country/Escuela AgrícolaPanamericana (EAP), Honduras, and AsianInstitute of Technology, Thailand

Zentralstelle fuer Ernahrung und Landwirtschaft (ZEL)Feldafing/Zschortau, Deutsche Stiftung fuer InternationaleEntwicklung (DSE), D-82336 Feldafing, Germany;Phone: 49-8157-938-0; Fax: 49-8157-938-777

Year-round Various courses and study tours tailored tomeet the training needs of a specific group oragency/Asian Institute of Technology,Thailand

Training and Consultancy Unit (see above)

16

Director: Dr. Hillary S. EgnaAquanews Editor: Danielle Z. ClairStaff: Kris McElwee, Matt Niles, Anu Gupta, JohnHayes, Heidi Furtado, and Xena Cummings

Aquanews is published quarterly by the InformationManagement & Networking Component of the PondDynamics/Aquaculture Collaborative ResearchSupport Program, Oregon State University, 400 SnellHall, Corvallis OR 97331-1641.<pdacrsp.orst.edu>

The contents of this newsletter are copyrighted bythe Pond Dynamics/Aquaculture CRSP. Copyright2000. All rights reserved including mechanical andelectronic reproduction.

Mention of trade names or commercial products doesnot constitute endorsement or recommendation foruse on the part of USAID or the PD/A CRSP.

The Pond Dynamics/Aquaculture CollaborativeResearch Support Program is funded in part by theUS Agency for International Development underCRSP Grant No. LAG-G-00-96-90015-00 and byparticipating US and host country institutions.

Oregon State University is an Affirmative Action/Equal Opportunity Employer.

Write to us or order publications at:Pond Dynamics/Aquaculture CRSPOregon State University400 Snell HallCorvallis, OR 97331-1641

You can also access CRSP publications electronically at<pdacrsp.orst.edu/pubs/publications.html>.

Or email us:Director: Hillary Egna egnah@ucs.orst.eduAssistant Director: Cormac Craven cravenc@ucs.orst.eduInformation Manager: Danielle Clair claird@ucs.orst.eduAsst. Info. Mgr.: Kris McElwee mcelweek@ucs.orst.eduPublications Ordering crsp.mail@orst.edu

I wish to discontinue receiving this publication.

I have discovered Aquanews online and no longer need toreceive it on paper.

My address has changed, and I have made correctionsto the label. (Please mail label to address above.)

CRSP Contact Information

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T he last quarter was a busy one for the CRSP pond,with many comings and goings. The ProgramManagement Office (PMO) welcomed Joan Westfall

as Administrative Program Assistant. Prior to joining thePMO, she worked at the Oregon State University (OSU)Foundation.

New to the Information Management and NetworkingComponent (IMNC) is graduate research assistant (GRA)Anu Gupta. Gupta studies in the Marine ResourceManagement (MRM) program at OSU, where she workson wetland restoration. Here at the IMNC, however, she isputting long-forgotten skills from her undergraduateEnglish degree to work as a technical editor.

The CRSP will miss its escapees, including Matt Niles,Kevin Bokay, and John Hayes.Niles is familiar to many of you asEdOp Net editor; he served overtwo years as GRA in the IMNC. Hehas moved to Hawaii, where he isworking on his MRM master’sproject, focusing on constructionsetbacks for coastal development.We at the IMNC office hope thatthose setbacks make for a bettersurfing experience…

Another graduate student toescape was John Hayes, who

moved from the IMNC to doing full-time graduate studyand research. (See p. 6 for a full profile on Hayes.)

Kevin Bokay, the former Administrative ProgramAssistant, has taken a faculty position at OSUs ValleyLibrary. In the Fall 1999 issue of Aquanews, Bokay statedthat he “always wanted to know more about themanagement of the University.” We hope that his newposition is giving him an innerwindow to the complicatedmachinations of the university.

The CRSP pond also felt ripplesfrom members outside the PMOand IMNC. US RegionalCoordinator for the Mexico ProjectMartin Fitzpatrick left OSU andhas moved to the OregonDepartment of EnvironmentalQuality. He will continue advisingstudents and working onReproduction Control Research.

Finally, Chris Brown, USRegional Coordinator for thePhilippines Project, moved fromthe University of Hawaii to Florida InternationalUniversity, where he will continue with his CRSP research.Brown will really be swimming with the fish as he directsthe university’s Marine Biology Program.

We wish everyone luck and success as they settle intotheir new niches!

Hil

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Departing GRA and EdOpNet Editor Matt Niles

Comings and Goings in the Pond

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Former Coordinator ofthe Mexico ProjectMartin Fitzpatrick