Ministry of Agriculture & Rural Development CARD Project Progress Report 027/05VIE: Development of clam culture for improvement and diversification of livelihoods of the poor coastal communities in Central Vietnam MS2: First Six-Monthly Report Institute Information Project Name Development of clam culture for improvement and diversification of livelihoods of the poor coastal communities in Central Vietnam (Project No: 027/05VIE) Vietnamese Institution Aquaculture Research Sub-Institution of North Central Vietnam (ARSINC) Vietnamese Project Team Leaders Mr Nhu Van Can (Project Director) Mr Chu Chi Thiet (Project Manager) Australian Organisation South Australian Research and Development Institution (SARDI) Australian Personnel Dr Martin S Kumar (Team Leader) Dr Bennan Chen (Senior Scientist) Date commenced February 2006 Completion date (original) February 2009 Completion date (revised) Reporting period February 2006 – October 2006 Contact Officer(s) In Australia: Team Leader Name: Position: Organisation Dr Martin Kumar Principal Scientist, and Program Leader, Integrated Biosystems Integrated Resource Management and Biotechnology South Australian Research and Development Institution (SARDI) In Australia: Administrative contact Name: Position: Organisation In Vietnam Name: Position: Organisation Telephone: 08 82075 400 Fax: 08 82075481 Email: kumar.martin@saugov.sa.gov.au Telephone: Fax: Email: Telephone: Fax: Email: Project Abstract Executive Summary 3.1 Project Implementation Progress 1.1 Key Highlights • Technological and socioeconomic evaluation completed Report submitted Report reviewed and accepted by CARD administration • Clam culture in ponds (production) experiments involving prawn farm effluent and influent is progressing well • Clam and prawn polyculture experiments is progressing well • Preliminary experiments on clam spat production produced encouraging results • Hatchery infrastructure established for spat production trials 3.1.2 Key outcome a) Socio economic study completed • Due to pollution as a result of poor water and nutrient management in the pond, shrimp culture is threatened with disease outbreaks Production cost is increasing and profitability is being reduced due to the use of more chemicals, lime, probiotic, etc for water and disease management • Banks are reluctant to extend capital due to inconsistent aquaculture production due to unreliable culture technique in the case of clam culture Similarly banks are hesitant to provided loans for shrimp culture because of the high risk due to disease out break • Lack of clam seed due to technology gaps is a major constraint, limiting the growth of clam farming development • Although there is a ready market for clam, the middlemen exploit the farmer and generate a low price, which results in a low profit margin for the farmer Farmers indicated the need for cooperatives to play a major role in marketing b) Production experiments made excellent progress Significant progress has been made in this section Preliminary results from production experiment indicated that clam can be successfully cultured in ponds This is the very first successful production of clam in ponds carried out in Vietnam Although the experiment is still in progress, the preliminary results indicated good clam growth and survival rate C) Initial trials of spat production completed and encouraging results obtained Introduction and Background A summary of the project objective, outputs expected and approach and methodology 4.1 Objective • The objectives of this project (027/05VIE) include the following: • To develop and extend the clam culture technology (hatchery and husbandry) • To sustain livelihoods of poor coastal farmers in the North Central provinces; • To develop a strategy which contributes to sustainable aquatic environment management using clam aquaculture to improve prawn farm effluent utilisation 4.2 Outputs Expected In accordance with expected output proposed, the fist six months were focused on following aspects related to achieving the development of clam production technology and hatchery operational procedure • Infrastructure establishment for clam production trials in ponds • Construction of lab facilitates for spat production experiments • Clam production in ponds started • Initial experiments on spat production started • Completion of Socioeconomic survey Above mentioned activities were completed as per the proposed logfram 4.3 Methodology Two visits by Australian Project Leader and scientists (one in April 2006 and the other August 2006) enabled to undertake major review of the project methodology, implementation strategy and resource and progress evaluation Scientific approach has been refined for implementing appropriate methodology for the experiments The advantages are: • Incorporate information from preliminary research results into the following experimental design • Clear scientific comparisons are possible • Avoid duplication of activities • Ease of management • Efficient use of resource 4.3.1 Summary for amendments and clarifications • Clam culture experiments a) It was decided to exclude the objective of determining optimum size from the first three experiments (Polyculture of Clam and Prawn, Clam culture in prawn farm effluent, Clam culture in prawn farm influent) as this could be done in other two experiments where objective of determining substrata will not be included The experiments would instead now focus on the following two objectives: i Determine suitable substrata ii Determine optimum stocking density b) Removal of Substrate Experimental Objective from the rotational clam culture in prawn farm and intertidal clam culture Experiment is recommended The Rotational Clam Culture experiment will instead focus on the following two objectives i Determination of optimum size ii Determination of optimum density Rotational clam culture prawn has to wait until September 2006 During this period results from other experiment would give an idea about the substrata Hence the decision to exclude substrata treatment from the rotational clam culture was taken c) Restriction of Intertidal Clam Culture to One Province was agreed The intertidal clam culture will be restricted to just one province with well-protected area The team took this decision of going ahead with intertidal clam culture after careful consideration of degree of risk, local support and collaboration, resource availability and degree of management difficulty Also the areas selected for the experiments are well known for clam occurrence d) Standardisation of sampling and measurement methods for all experiments to reduce data collection error was advised Due Standardisation of methods for measurement and use of measuring equipment, random sampling / sample selection from ponds, and rotational roster for data collection staff; Determination of sampling differences between staff was established • Hatchery Experiments Based on the preliminary results from the hatchery experiments the following sections revised and refocused i Brood Stock Conditioning ii Breeding and Spawning techniques iii Larval Rearing / Culture Methods iv Nursery (inclusive of Larval Settlement) a) Experiments to determination of suitable temperature range for brood stock conditioning will be further focused in the next experiment b) Salinity Experiment to Hatchery Larvae Rearing Experiment A Salinity Experiment to investigate the effect of salinity on growth and survival Each of salinity concentrations between 10PPT and 35PPT were stocked with 25,000 larvae and measured for growth and survival rates until pediveliger or late-umbo development stage (approximately 10 days) c) Conduct of two larvae culture systems for comparison, in the larvae stocking density and water change component of the Larval Culture Experiment: • Option one: the experiment will focus on larvae stocking density (with level: – 10 – 15 larvae/ml) with flow-through water system • Option two: the experiment will focus on larvae stocking density (with level: – 10 – 15 larvae/ml) with water change every 24 hour, 36 hour and 48 hour The two options were selected due to the need to determine the suitability of a single system for future experiments that would give a survival rate closer towards survival rates in literature d) Introduction of a Nursery Experiment with the objective of determining optimal nursery conditions to maximize growth rate and survival rate of spat and juvenile of clam Specific objectives include: • To determine feeding regime • To determine optimum stocking density • To determine optimum substrate (artificial bottom and solid bottom/nylon mesh only) • To determine nursery type (comparison of the hatchery system/flowthrough system with floating raft in booming pond systems) • This experiment will be described in greater detail below e) Nursery Experiment specifications were finalized and the specifications were as follows: • Method: The clam spats in their first week after settlement will be transferred to nylon meshed screens for grow out Different mesh size of screens will be used for grading the spats during growth out period Following two methods are proposed for spat grow-out • Option 1: Indoor flow-through system (consist of holding tanks with size of 0.6 x 1.2 x 2.4 m): Water with algae (food) from the blooming pond (algal pond) will be fed into holding tanks containing spats and then returned back to algal pond This continuous feeding will be carried out using electric pump • Option 2: Outdoor pond system: In this system, spats will be reared in the floating rafts kept within the blooming pond Water quality in blooming pond will be managed by adopting strict pond fertilization regime and pond management measures including water levels may need to be controlled to make sure that there are enough algae for feeding spat during the nursing period The experiment will be focused on the following parameters: • type of substrate : a o screen bottom b o solid bottom • type of the nursery system a o flow-through system b o Floating raft system st Parameters Substrate Six-monthly Report Indoor flow-through system Screen substrate Solid substrate Outdoor pond system (floating raft) Screen substrate Solid substrate Stocking density Selected species of algal culture (plastic bags) 150g/m3 Species 200g/m3 250g/3 Species Species Mix or 150g/m3 200g/m3 250g/3 During the experimental period water quality parameters such as oxygen (6-8 mg/l), pH (8-8.5), ammonia 88% secondary and above education) • High levels of attendance of aquaculture training (86%) c) Economic Issues • Finances from Banks and other Lending Institutions • Funding from the Vietnamese Government • Middlemen Margin Affecting Profits • No Support Role by Cooperatives • Key outcomes and Recommendations a) Impact • Clam culture can make a difference in poor communities by providing economic and food security • Information from this project can be used for local government aquaculture planning • Clam culture can act to remediate the impacts of prawn farming so as to increase sustainability of prawn farming in Vietnam b) Recommendations • Should develop hatchery technology • Should develop grow-out and production technology • Development of a business model to enable implementation by farmers • Cooperatives and government should help in the marketing of Clam culture and Clam consumption 5.1.2 Production Experiment Establishment of infrastructure and part of the results were included in this section Experiments are in progress and complete results will be reported in the next report 5.1.2.1 Infrastructure a) Effluent and Influent pond systems set up in Thanh Hoa An effluent system for two treatments – bottom treatment, there are ponds for triplicates of substrata such as sand bottom, clay-sand bottom and clay bottom and Density treatment, there are ponds for triplicates of density levels (90clams/m , 2 120clams/m and 150clams/m ) comprised of a total of eighteen 9m ponds were set up in Thanh Hoa Province (Fig 1) An influent system built (similar to effluent) and experiments is being conduced the same as treatment included in effluent (Fig 2) b) Clam and prawn polyculture An polyculture system for one treatment – Density treatment: there are nine 50m ponds for triplicates of density levels such as 2 60clams/m , 90clams/m and 120clams/m This experiment also set up in Thanh Hoa Province Fig Density – Influent / Effluent System: project staffs are checking growth rate of clam in pond c) Results obtained so far Since this experiment is in progress, results presented here only up to September 2006 Analysis will be undertaken after the completion of the experiments A comprehensive analysis and discussion and conclusion will be included in the next report (5/ml) (200,000 larvae), D2 (10/ml) (400,000 larve) and D3 (15/ml) (600,000 larvae) Data was collected on growth rate, survival rate and Days to Settlement until pediveliger or late-umbo development stage (approximately 10 days) Water change was carried out every 48hours in the morning and larvae count carried out after water change Sieves of 80µm to 150µm were used to filter out the larvae and to clean the larvae Figure 19 Changing water from rearing larvae tank (left) and counting larvae of clam (right) Figure 20 Larvae of clam (M.lyrata) at D-veliger stage (left) and umbo stage (right) Figure 21 Larvae of clam (M.lyrata) at metamorphosis (food) stage and settlement stage Salinity experiment: Each container was stocked with 25,000 larvae and measured for growth rate, survival rate until pediveliger or late-umbo development stage (approximately 10 days) Water change was carried out every 48hours in the morning and larvae count carried out after water change Sieves of 80µm to 150µm were used to filter out the larvae and to clean the larvae Figure 22 A system comprising eighteen 10L containers were used to create triplicates for salinity concentrations between 10PPT and 35PPT in 5PPT gradients c) Key Results I Density experiments • Growth Rate Growth rates for M Lyrata larvae displayed similar values across all three densities (5/ml, 10/ml and 15/ml), showing significant differences only after day By Day 10, Density (5/ml) had the largest larvae size (202µm) Density (15/ml) with larvae of (196µm) and Density (10/ml) had the smallest larvae size (189µm) Grow th rate of M.lyrata larvae versus Time, per Density Size of Larvae (in Micron ) 220 200 180 160 140 120 100 80 56 910 Age of larvae (in days) Figure 23 Growth Rate of M lyrata Larvae versus Time, per Density (Optimum Density in Hatchery Experiment) • Survival Rate Figure 24 shows spats from the Novel Nursery System at 45 days Table and Figure 25 below summarises the survival rate of the M lyrata larvae for each of the three densities D1 (5/ml), D2 (10/ml) and D3 (15/ml) by total count In addition, Table … expresses the survival rate by percentage This is graphically represented by Figure 25 The starting larvae count for the densities was 200,000, 400,000 and 600,000 respectively It is important to note that by Day 5, total counts for all three densities had dropped to between 8.44% and 13.33% of their original counts in the same volume of substrate (40 litres), with between 26,600 and 53,300 larvae This changes the larvae rearing density values as factors against survival Table Survival Rate of M (averaged) Days Density D1 (5/ml) 200,000.00 D2 (10/ml) 400,000.00 D3 (15/ml) 600,000.00 lyrata Larvae per Density, by Total Count 115,555.56 195,555.56 182,222.22 26,666.67 33,777.78 53,333.33 21,333.33 26,666.67 44,444.44 14,222.22 23,111.11 37,333.33 10 12,444.44 22,222.22 34,666.67 Total lavae count 700,000 600,000 500,000 400,000 300,000 200,000 100,000 910 Age of larve (in days) Figure 25 Survival Rate of M lyrata Larvae per Density, by Total Count (Optimum Density in Hatchery Experiment) Table Survival Rate of M lyrata Larvae per Density, by Percentage Days Density D1 (5/ml) D2 (10/ml) D3 (15/ml) 100.00% 100.00% 100.00% 57.78% 48.89% 30.37% 13.33% 8.44% 8.89% 10.67% 6.67% 7.41% 7.11% 5.78% 6.22% 10 6.22% 5.56% 5.78% Figure 26 Survival Rate of M lyrata Larvae per Density, by Percentage (Optimum Density in Hatchery Experiment) It was observed that D3 had the most rapid decrease in survival rate by Day 3, down to 30.37% By Day however, both D2 and D3 had similar survival rates of 8.44% and 8.89% Development of clam culture for improvement and diversification of livelihoods of the poor coastal communities in Central Vietnam respectively It was also observed that whilst the D1 survival rate was on average higher than D2 and D3, its decrease in survival rate also dropped to 13.33% by Day The decrease (drop) in survival rate between Day and Day 5, as expressed as a percentage of the Day as 100%, is as follows (Table 3) Between Day and Day 5, D2 had the greatest drop in survival rate of -81.92%, whereas D3 had the lowest drop of -70.73%, taking into account that by Day 3, only 30.37% had survived in D3, as compared to 57.78% and 48.49% in D1 and D2 respectively Table Decrease in survival rate between Day and Day 5, as expressed as a percentage of Day Days Density Decrease in survival rate D1 (5/ml) 57.78% 13.33% - 76.93% D2 (10/ml) 48.89% 8.44% - 81.92% D3 (15/ml) 30.37% 8.89% - 70.73% • Days to Settlement The following Table and Figure 27 summarises the average days to settlement and percentage survival of the M lyrata larvae Density (15/ml) took the longest time (10.67 days) to larvae settlement but had a percentage survival (15.56%) higher than Density (5/ml) at 6.67% Density (10/ml) had the highest percentage survival at 31.11% whilst taking 9.00 days to settlement Table Larvae Rearing Density Experiment – Days to Settlement Density Days to Larvae Settlement Percentage Survival (average) (average) 8.33 6.67% D1 (5/ml) 9.00 31.11% D2 (10/ml) 10.67 15.56% D3 (15/ml) Figure 27 Days to M lyrata Larvae Settlement versus Density and Percentage Survival (Optimum Density in Hatchery Experiment) II Salinity experiment • Growth Rate For growth rate versus salinity, larvae in 20PPT and 25PPT salinity levels were 164μm by Day 10, as opposed to 160μm for 10PPT salinity, and 158μm for 30PPT Larvae sizes at 20PPT and 25PPT were consistently higher than other salinity levels, and 35PPT produced a spike in larvae size of 130μm by day Figure.28 Growth Rate of M lyrata Larvae versus Salinity (Optimum Salinity in Hatchery Experiment • Survival Rate For all salinity levels, highest mortality occurred between Day and Day 2, with 53.33% survival at 20PPT, 48.89% at 20PPT, 46.67% at 15PPT, 33.33% at 10PPT, 26.67% at 30PPT and 8.89% at 35PPT Salinity levels of 15PPT, 20PPT and 25PPT provided for higher survival levels compared to other salinities, but no significant relationship could be observed between these three concentrations The weak relationship that could be observed was 15PPT providing for higher survival rate than 25PPT, with 20PPT with the highest survival rate By Day 4, all larvae in 35PPT were mortalities Figure 29 Survival Rate of M lyrata Larvae versus Salinity (Optimum Salinity in Hatchery Experiment) Figure 30 Days to settlement in different salinity levels d) Discussion I Density experiment • Growth Rate Whilst it is expected that increasing larvae rearing density should decrease growth rates due to crowding and competition for resources, D3 had a slightly larger average size of 196µm compared to 189µm for D2 by Day 10 This lack of significant difference in growth rates could be due to the mortalities by Day resulting in low survival rates between 8.44% and 13.33% As the total counts for all three densities had dropped to between 26,600 and 53,300 larvae in the same volume of substrate (40 litres), this changes the larvae rearing density values as factors against survival The new density values are calculated in Table below Table Impact upon Density of Survival Rate of M lyrata Larvae Days Density D1 (5/ml) D2 (10/ml) D3 (15/ml) Day Count 26,666.67 (13.33%) 33,777.78 (8.44%) 53,333.33 (8.89%) Volume of Substrate 40L 40L 40L New Density at Day 0.67/ml 0.85/ml 1.33/ml The low densities of between 0.67/ml to 1.33/ml (as compared to between 5/ml and 15/ml at the start of the experiment) likely contributed to the lack of significant difference in growth rates For the second six-monthly report, it would be important to calculate growth rates in relation to the resultant density due to survival rate Growth rates would therefore have a correlation between survival rates / densities However, it should be noted that the 2:4:6 (D1:D2:D3) total count ratio at the start of the experiment was ‘generally maintained’ throughout till Day 10 by natural adjustment The following Table demonstrates the D1:D2:D3 ratio by rounding off the total count to one decimal place ratios Table Survival Rate of M lyrata Larvae per Density, by D1:D2:D3 Ratios from Total Count Days Density D1 (5/ml) D2 (10/ml) D3 (15/ml) 1.2 2.0 1.8 2.7 3.4 5.3 2.1 2.7 4.4 1.4 2.3 3.7 10 1.2 2.2 3.5 It may also be useful to calculate the average or end-point percentage difference between growth curves of the different densities in the second stage As significant trends are not identifiable from the current data set, the experiment should continue into the second stage A repeat experiment with fixed densities of M lyrata could also be conducted to calculate growth rates against fixed densities More significantly different densities should also be trialled • Survival Rate In other similar research / literature, survival rates in general mollusc culture, for exemple hard clam (Mercenaria mercenaria), only 10 percent of fertilized eggs survive to metamorphosis stage (Jack M Whetstone, Leslie N Sturmer and Michael J Oesterling, 2005) The decrease in survival rate between Day and Day to between 30.37% and 57.78% could be due to natural selection of the larvae and would be acceptable if compared to high-technology farming systems’ average of 50% However the decrease in survival rate between Day and Day of a further -70.73% to -81.92% , resulting in average percentage survival of only 6.67% (D1), 31.11% (D2) and 15.56% (D3) suggest that other factors are causing mortalities or affecting count This could be because of stress due to the use of a water-change system as opposed to a recirculation system For commercially viable larvae rearing operations to meet demand in Vietnam, a suitable system must be established to maintain survival rates similar to high-technology mollusc farming systems employed elsewhere Therefore, there may be a need to conduct trials to compare water-change and recirculation system survival rates, as well as to identify environmental factors such as nutrition and water quality that could be contributing to mortalities The availability of nutrition should take into account the duration of yolk sac nutrition in the larvae Also, in order to establish survival trends between water changes, counts should be conducted daily for the first week of experiment • Days to Settlement No significant trends comparing percentage survival versus days to settlement can be observed from the data set A weak trend could be observed when days to settlement were compared with densities, with lower densities allowing for quicker days to settlement However, it should be noted that the densities of larvae were between 0.67/ml to 1.33/ml by day where days to settlement were between 8.33 and 10.67 days Therefore, the densities by settlement were not significantly different enough to establish a strong trend in relation to settlement speed II Salinity Experiment Larvae sizes at 20PPT and 25PPT were consistently higher than other salinity levels, and 35PPT produced a spike in larvae size of 130μm by day Survival rates appear to favour lower salinity environments, with 20PPT the most favorable However, considering in other similar research / literature, survival rates in general mollusc culture, for example hard clam (Mercenaria mercenaria), average 10% survival up to metamorphosis stage (Jack M Whetstone, Leslie N Sturmer and Michael J Oesterling, 2005) The maximum survival rate at 20PPT of 31.11% and the average survival rate for concentrations between 10PPT and 30PPT at 22.66% indicate that more work needs to be done to identify survival rates in the context of both salinity and stocking density • Recommendations for next project phase Growth Rates i Continue experiment to establish more significant trends over a longer period of time Place emphasis in the confirmation of growth trends and calculate average or end point percentage difference between growth curves of the different densities ii Conduct a repeat experiment with fixed densities of M lyrata (eg by reduction of substrate volume for surviving larvae) to calculate growth rates against fixed densities iii If possible, the experimentation with density differences of 200% and 400% or more should be trialled, as the current 100% and 150% differences may not be sufficient to establish clear trends between densities Survival Rates i Trials to compare water-change and recirculation system survival rates should be conducted, with counts conducted daily and pre-water change for the first week Nutrition and water quality (Temperature, DO etc.) should also be measured to establish any impact upon survival rates ii In later stages (to promote farmer uptake), to determine what is the best system – complexity and cost of recirculation systems – perhaps levels of complexity according to cost so that farmers can afford to use Most expensive system may use UV, protein skimmer, biofilter etc., least expensive system may use sand filter, even natural sunlight filter Days to Settlement i Conduct a repeat experiment with fixed densities of M lyrata (eg by reduction of substrate volume for surviving larvae) to calculate days to settlement against fixed densities 5.2 Smallholder Benefits 5.2.1 Opportunity to utilize the brackish water ponds for clam production The evidence that clam can survive and grow in pond opens opportunity for farmers to utilize the brackish water ponds where the shrimp industry recently has been collapsed due to bad management 5.2.2 Easily Applicable Farming Knowledge Factors such as stocking density and salinity are within the capabilities of smallholder end-users to monitor and manipulate By focusing upon the research and understanding of the impact of such factors on survival and growth of M lyrata and its larvae, the teams at ARSINC are building the knowledge base for farming practices that can be applied by smallholders 5.2.3 Low Investment Risk The focus on low-cost, reliable production and hatchery techniques and infrastructure provide for low investment risk to the smallholder and smallholder communities 5.2 Maximizing Commercial Potential through Knowledge The following table summarizes the implications of the knowledge generated by this project for the smallholder’s commercial production potential Table Technology Implications for M lyrata Commercial Production Farming Knowledge Implications for Commercial Production Component Production Density • Farmers need to know optimum stocking density that provide for maximum productivity per m2 pond area Substrate • Farmers need to know which sediment substrate clam can be grown on as this may affect farmers of different regions where there is different soil type Influent / Effluent / Polyculture Pond System • An influent pond system may be useful for water treatment prior to prawn culture use in places where water quality is not good enough for prawn culture • An effluent pond system may be useful for prawn culture to reduce pollution and enable more sustainable prawn culture • A combination of both pond systems (polyculture) would be useful to supplement farmer income (both prawn and clam) as well as provide for sustainable aquaculture and/or bioremediation of prawn farming areas Hatchery Spat Production Technology for M lyrata clam culture • Easy to use, low-cost indigenous (developed by ARSINC) system that can be implemented on farms or in regional cooperatives • Reduce collection of spats from wild so as to reduce ecological impact along Vietnam coastline Hatchery / Broodstock Conditioning Algae feed composition • Enable hatcheries and regional cooperatives to culture feedstocks (using pure cultures from ARSINC and other government suppliers) for hatcheries to use in their spat production Hatchery / Larvae Rearing Stocking density survival / growth rates Salinity survival / growth rates Stocking density Days to Settlement Breeding / Spawning Breeding / Spawning Inducement Factors • Enable farmers to create their own broodstock • Enable regional hatcheries to achieve optimal larvae rearing productivity • Enable regional hatcheries to achieve optimal larvae rearing productivity, controlling salinity if necessary • Enable regional hatcheries to know how many production cycles can be achieved per season and how to increase frequency of spat production • Enable regional hatcheries to know what factors induce breeding and spawning, that can be controlled by the hatchery 5.3 Capacity Building 5.3.1 ARSINC At least technical staff directly involved in the project activities have opportunities to improve their knowledge, experience in both hatchery and grow out production of clam culture Researchers of ARSINC involved in this project have chance to approach updated research methodology and gain more experience in research, design, implementation and reporting as well as international communication There were students from University of Vinh selected to their BSc thesis on Clam hatchery production under ARSINC supervision students from Aquaculture College No4 were selected for their Internship on grow out production of clam under supervision of ARSINC 5.2.3 End-users Due to this being the first research phase of the project, several farmers at the experimental site were hired and trained for research activities participation 5.3.3 Enhanced reputation and relation ship withother institutions and collaborators The project activities have been well introduced and have good comments from scientific committee of ARSINC This accelerates collaboration and contribution from other projects implementing within ARSINC and RIA1 eg NORAD funded project and AIDA project 5.4 Publicity Project team presented a presentation to introduce the first result on hatchery production of clam in the National Marine Aquaculture Conference (October 2006 – Ha Long city The project has been collaboration with AIDA project to organize training course on lam culture lectured by the project technicians 5.5 Project management issues Project contract signing has been delayed due to finalizing the agreements between SARDI and AusAID contractor Therefore revised milestones dates were prepared and submitted There is no other issues which can be reported this time Report on Cross-Cutting Issues 6.1 Environment It is highly unlikely that this project will result in the development of technologies that will have negative environmental impacts The primary objective of the project is to develop clam aquaculture using sustainable practice Apart from economic improvement the project also develop strategy for effluent management form prawn farm 6.2 Gender and Social Issues Clam aquaculture in Vietnam, is a family or household activity Women undertake 5060% of the work including husbandry, harvesting and marketing Therefore, aquaculture activities are very much a household duty If the proposed project is properly implemented through making relevant information more available and improving the skills of the information deliverers, the results will significantly increase women’s contribution in terms of income and food and therefore their importance and self esteem The Technological and socioeconomic study conducted by project team indicated that farmers received low prices for clam due to exploitation by middle men Cooperatives need to play a major role in marketing the clams Study further confirmed that shrimp and clam culture systems are seen as the backbone of the coastal community Clam culture is making more profit than shrimp, due to less capital cost and reduced risk It’s successful expansion will definitely improve the family income and living standards for the people in the provinces 6.3 Implications on other projects Finding from this project provides valuable information for developing strategic plan and guidelines for coastal aquaculture development in the region The NORAD project and AIDA project are closely collaborating with CARD project as there are good synergies Implementation & Sustainability Issues 7.1 Issues and Constraints No new major constraints identified Two key technical issues need to be resolved for successful implementation of the project • Develop methods to grow clam in ponds and prove commercial feasibility During the first six months team successfully demonstrated clam can be grown in ponds showing commercial viability Experiment is still in progress and the complete reporting will be done in the next report The issue is farmers are highly eager to culture clam before the technology is formally/properly transferred to them • Commercial hatchery technology is another key technical issue need to be resolved During the first six months team showed the potential success in artificially producing spats However, survival and growth rates can be improved by providing better environmental conditions This will be undertaken in the next set of experiments 7.2 Options Technology transfer will be carried out through demonstration by implements participatory approach Lead farmers who are already participating in the experimental trials and selected additional farmers will be involved in the technology demonstration 7.3 Sustainability No new major constraints identified 7.4 Next Critical Steps Following are the two next critical steps • Resolving the technological issues related commercial clam hatchery procedure development • Successful implementation of inter-tidal clam culture All other key experiments will continue based on the proposal and recommendations specified in the report Clam Culture in Inter-tidal Area A system comprising twenty-four 50m2 pilots were set up for treatments such as size treatment and density treatment Size treatment – There are two different size (height) of clam using in experiment such as 1cm and 2cm Density treatment – There are different densities using such as 60clams/m2, 120clams/m2, 240clams/m2 and 360clams/m2 Conclusion Project is progressing well in accordance with proposed plan There is no unexpected issues were identified Development of clam culture for improvement and diversification of livelihoods of the poor coastal communities in Central Vietnam 42 ...1 Institute Information Project Name Development of clam culture for improvement and diversification of livelihoods of the poor coastal communities in Central Vietnam (Project No: 027/05VIE) Vietnamese... both D2 and D3 had similar survival rates of 8.44% and 8.89% Development of clam culture for improvement and diversification of livelihoods of the poor coastal communities in Central Vietnam. .. rate (height) of M lyrata in effluent Pond, by Substrate Development of clam culture for improvement and diversification of livelihoods of the poor coastal communities in Central Vietnam Growth