Sustainable Coastal Zone Management and Aquaculture. Aquatic Food Supply

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1 26 Sustainable Coastal Zone Management and Aquaculture Keith Jeffery BSc. DMS. Aquaculture and Aquatic Animal Health Business Development. Cefas, UK Food from aquatic environments contributes to human nutrition and health, but maintaining long-term production and supply from both wild-capture fisheries and aquaculture is challenging. Production must be sufficient, safe and nutritious but also environmentally, socially and economically sustainable. Global demands are expected to increase in future decades. Median projections suggest global human population growth by 2050 of 2.4 billion, to over 9.7 billion. Food demand is expected to rise faster than population growth, because a larger proportion of middleclass people with greater spending power will consume more animal protein. Aquatic Food Supply Sufficient Safe Sustainable Shock-Proof Sound Food supply is Sufficient to meet the needs and Wants of society. Food production poses minimal risksto prople and the environment and the food producted is safe to eat. Food is available now and for future generations. Food supply is resilient to shocks in production systems and supply chains. Food production processes meet legal standards for animals and people and the ethical expectations of society. Figure 1: Five elements of aquatic food supply which contribute to food security Envirocities emagazine

2 27 Issue 14 May 2016 With wild fisheries production unlikely to increase significantly in the future, aquaculture represents the largest growing sector of global aquatic food production. Figure 2 Trends in global production from marine (red) and freshwater (yellow) capture fisheries and aquaculture (blue). Climate change might affect food security via extreme weather events and potential reduction in land available for agriculture. Competition for terrestrial food growing space will be compounded by increasing urbanisation and demand for biofuel and animal feeds. Sustainable aquaculture can provide food with little or no requirement for arable land whilst offering better food conversion (than terrestrial livestock), using much less feed per unit of production. Expansion of aquaculture does have implications for coastal zone use, so strategic management and regulations are important to its future development. A Magazine for the Environmental Center for Arab Towns

3 28 Existing and Emerging Aquaculture Techniques. Globally aquaculture produces a diverse range of species in different culture systems. Whilst some systems are long established, others are rapidly evolving the engineering and technology solutions required to make the industry sustainable. Systems likely to be found around the Arabian gulf include: Net-pen culture, an economically efficient form of aquaculture. Species farmed around the Arabian gulf include sea-bream, tuna and groupers with future opportunity for producing snapper, pompano, amberjack and trevally. These systems come with elements of environmental risk that require appropriate management. Risks include build-up of organic waste, inappropriate use of medicines, and escapees impacting on wild fish stocks. Figure 3 Net-pen culture, Cesme Izmir, Turkey FAO Aquaculture photo library / FAO SEC Figure 4 Experimental version of a submersible fish Aquaculture photo library / N. Sims Offshore aquaculture development offers opportunity for expansion with increased availability of space, better background water quality, reduced environmental impacts, and less competition with other sectors. Submersible cages would reduce visual impacts and risk of wave damage resulting in stock loss, enabling finfish farming in more exposed environments. Challenges remain regarding operation offshore. Figure 5: Aqua Dome project, Norway. SINTEF PowerPoint. Closed floating pens are being trialled to reduce environmental impacts. Water is pumped in, rather than relying on free movement through the mesh of open net-pens. Potential benefits include capture of solid wastes, reduction and control of nutrient and chemical discharges, containment of stock, and a physical barrier preventing pathogen entry and exit. Envirocities emagazine

4 29 Issue 14 May 2016 Bivalve culture requires no supplementary feed as they filter-feed, improving water quality and providing ecosystems services. Diverse shellfish cultivation systems include floating longlines and rafts, bottom culture, and intertidal trestles and bouchet poles. Shellfish can pose food safety risks due to their tendency to accumulate toxic algae, viruses, bacteria or chemicals to levels that become harmful if consumed. This area needs careful regulation to ensure food safety. Figure 6 Bivalve longline watch Figure 7 Modern land-based Power-point. Recirculation aquaculture systems (RAS) technology is still evolving and improving. These land-based systems operate by recirculating and filtering water. With technological improvements, reduction of capital costs, economies of scale and linkage with renewable energies, RAS offer promise for the future, especially for higher value species such as sturgeon or amberjack. Figure 8 Automatic feeder used for shrimp. Fish Farming Centre, Aquaculture photo library / V. Crespi Land-based costal ponds produce various high value species such as prawns and shrimp whilst enabling partial control of environmental conditions. A Magazine for the Environmental Center for Arab Towns

5 30 Integrated multi-trophic aquaculture (IMTA) maximises the use and retention of nutrients with the emissions from fed species providing inputs (fertilizers, food) for others. The concept of IMTA is that farms combine aquaculture of finfish or shrimp with species that extract dissolved nutrients (e.g. seaweed) and suspended solids (e.g. shellfish) to create balanced systems with minimal environmental impact. Figure 9 Integrated multi-trophic aquaculture SL Holdt Holdt and Edwards 2014 Envirocities emagazine

6 31 Issue 14 May 2016 Aquaponics combines the culture of fish and plants in recirculating systems where dissolved waste nutrients are recovered by plants. These systems have a clean, green image producing food close to the markets. The challenge for aquaponics is to become commercially viable. Figure 10 Aquaponics Ahmed Regulation of aquaculture to protect the environment National administrators must ensure that aquaculture development within coastal zones protects the environment, whilst enabling economic development and ensuring the seafood produced is healthy, nutritious and safe. Regulation includes: operators should Liaise directly with regulators to ensure that they understand their responsibilities. Benefits of an appropriately regulated aquaculture sector. Licensing appropriately located sites, where mitigation measures, good practices and an ecosystem approach have been implemented; Monitoring with risk-based inspections to ensure operators comply with the licence authorisation; Strategic Planning for marine aquaculture development, ensuring linkage with other marine industries, and that Allocated Zones for Aquaculture (AZAs) are provided; An appropriately regulated aquaculture sector will deliver a safe and sustainable supply of healthy seafood that contributes to food and nutritional security, increased employment, and economic growth in coastal communities. A well planned and regulated sector reduces conflicts between stakeholders ensuring long-term sustainability within the coastal zone. Charging that ensures regulatory costs are proportionate to the business. The aquaculture industry needs to ensure that Technology and systems are appropriate to the local environment. Management should incorporate a broader ecosystem-level approach encompassing all environmental impacts (e.g. animal health, discharges, alien species, veterinary medicines) and A Magazine for the Environmental Center for Arab Towns