PROBLEMS
Although there are a number of
ways aquaculture benefits the environment, there are
also several concerns regarding its use. In many cases, THE PROBLEMS have already transpired and have been re mediated. Regardless, aquaculture does pose some problems and
concerns that have needed to be addressed.
- ENVIRONMENT: Like a giant aquarium, land-based fish farms must change their tanks' dirty water. Depending on the system's set-up, this can result in the discharge of significant amounts of wastewater containing feces, nutrients and chemicals into the environment. Nutrients can result in algae blooms which eventually remove dissolved oxygen in the receiving waterway, or eutrophication. A zero oxygen content results in fish kills. In addition, chemicals are commonly used in the aquaculture industry, such as antibiotics and water treatment agents.Aquaculture systems should be closed, or its wastewater treated prior to discharge.
- DISEASE: Aquaculture operations can spread parasites and disease into the wild. Just as commercial chicken coops must be kept clean and are notorious for disease, farmed fish and shellfish are subject to the same circumstances. Farmed fish have an increased chance of getting parasites such as sea lice, as opposed to fish in their natural environment. Farmed fish are also exposed to diseases through the use of unprocessed fish to feed as their food source, as opposed to safer processed fish pellets.
- ESCAPEES: Aquaculture is one of the largest causes in which foreign species are introduced into new areas, creating invasive species under the right conditions. Farmed fish can escape from their pens, damaging both the environment and threatening native fish populations. Invasives can compete for food and habitat, displace indigenous species, and interfere with the life of wild species. They can also carry diseases or parasites that might kill native species. In addition, escapees that are able to breed with the wild stock can dilute the natural gene pool and threaten the long-term survival and evolution of wild species.
- SECONDARY IMPACTS: Because farmed fish need a food source, other wild species are threatened to be overfished for the manufacture of fish food. Because most farmed fish are carnivorous, they are fed either whole fish or pellets made from fish. Species such as mackerel, herring and whiting are threatened from the pressure to create food for other farmed species.
- CONSTRUCTION: Both land-based and aquatic wildlife can lose their habitats through the building of aquaculture facilities along the coast, where clean and natural water can be accessed for its processes. In one famous example, in Asia and Latin America, mangrove forests have been cleared to make space for shrimp farm
- FISH FEED REQUIREMENT: Farmed carnivorous fish, such as salmon, require a food source which is high in fish-derived proteins. This generally comes from wild capture fish at the bottom of the food chain, which are not usually marketed for human consumption. There are two key challenges to developing a sustainable aquaculture industry. The first is to find a source of food for the farms which does not depend exclusively on wild fish being caught. The second is to ensure that any wild fish used as feed is caught in a sustainable manner. This is because removal of these species low in the food chain can have serious implications for fish stocks, the food web and other wildlife including sea mammals and seabirds.
- SITES IN VULNERABLE HABITATS: There are a number of problems which stem from fish farms being located in inappropriate areas. These include vulnerable habitats (both terrestrial and marine), essential fish habitats or areas with high concentrations of wild fish. Some of the problems can include organic waste accumulation on the seabed under sea pens – resulting in localised degraded water quality sea lice and other disease transfer; and altered foodwebs from escaped individuals as described below.
- ESCAPEES: When fish escape from a farm open to the sea, this can lead to problems for the wider ecosystem. This is because escaped farmed fish can interbreed with wild fish of the same species, resulting in genetic dilution (domestic farmed fish can have low genetic variation); they can spread disease; they can displace eggs of wild fish and they can put pressure on natural resources through competition with wild fish.
- ALIEN INTRODUCTIONS: Invasive non-native species are recognized as one of the main causes of global biodiversity loss. Recent reports suggest that this is a problem which is increasing. Aquaculture has benefited from the farming of alien species, but without proper management this can lead to altered ecosystems and biodiversity loss. An example of this is the introduction of the Pacific oyster into the UK. The Pacific oyster was introduced into UK waters in the 1960s for aquaculture purposes and it was seen as a more commercially viable alternative species to the native oyster. Since this time, the Pacific oyster has spread into the wild. Natural populations of the Pacific oyster can now be found in the Kent and Essex area resulting in reef formations which have displaced or modified some areas of the native oyster and biologically diverse marine environments. Natural England has produced a report about this specific example.
- POLLUTION: A range of chemicals can be used in marine aquaculture operations such as disinfectants, anti-foulants and medicines (including vaccines). These marine pollutants can be toxic to wildlife and can cause significant damage to the wider ecosystem, especially anti-foulants containing copper.
RESEARCH
OF AQUACULTURES
Research in Aquaculture involves
many aspects of aquaculture in order to support the nation’s effort to promote
large-scale sustainable practices. This group is equipped with facilities such
as outdoor tank culture systems, in-door glass aquarium systems, feed making
equipments, biochemistry and molecular laboratories. There are 3 core
laboratories, Laboratory of Fish Genetics, Laboratory of Fish Nutrition and
Laboratory of Fish Biology. The main research activities cover various aspects of aquaculture and
aquatic organism related areas, including diet development, culture techniques,
hatchery set ups, reproduction, biotechnology and population management. The
Laboratory of Fish Genetics is focuses on population genetics studies to
investigate local genetic population structure of cultured or endangered
species. The Laboratory of Fish Nutrition is well known in the area of feed
development; feed biochemistry for locally cultured species. In the Laboratory
of Fish Biologyx various research projects dealing with larviculture, protein
and DNA studies are carried out. Ornamental fish, an important branch of
Malaysian aquaculture is also an important component of aquaculture research.
ShrimpNews.com posted a great article on July
5th, 2015 about India shrimp exports. It has reached an all time high, with the USA being the
largest market. During India’s most recent fiscal
year April 1, 2014, to March 31, 2015, abbreviated as “FY15” exports of marine
products reached an all-time high of $5.5 billion. Shrimp accounted for 34% of the
quantity of marine product exports and 67% of their value. The overall export of shrimp
during FY15 was 357,505 metric tons, worth $3.7 billion. The USA was the
largest market for India’s shrimp (112,702 tons) followed by the European Union
(81,952 tons), South East Asia (69,068 tons) and Japan (30,434 tons).
(ShrimpNews.com).
FUTURE OF AQUACULTURES
FISH HARVESTED FROM AQUACULTURE MAKE UP 46% OF THE WORLD’S SEAFOOD
SUPPLY (FAO 2010).
In the coming years, aquaculture
will be the only way to fulfil mankind’s needs for animal proteins, due to the
increasing human population, combined with stagnation of yields from capture
fisheries. We share our expertise in the fish
farming area and help you improve the productivity and profitability of your
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wide range of integrated and complementary services, covering all aspects of
the aquaculture business, from feasibility study to project implementation,
farm management and technology transfer
FUTURE AQUACULTURE DEVELOPMENT
In summary, there is
a need to develop aquaculture in Malaysia in order to reduce the high levels of
exploitation and dependence on natural fisheries resources. This will provide
the 250,000 tonnes of fish required by the year 1995 in Malaysia. There has been a
tremendous increase in the disposal of effluents and wastes into freshwater
bodies and coastal waters due to the development of both land-based industries
and aquaculture. There has also been a growing awareness of the importance and
need to preserve the environment. These are constraining factors that can slow
down the present growth of aquaculture in Malaysia. To ensure that progress and
growth of the aquaculture industry will not be affected by: (i) the lack of
available suitable sites for aquaculture; and (ii) controls intended to promote
and protect the environment, it is important that the Malaysian government
adopts various strategies to look into the matters.
These should include:
- Implementing and enforcing the present regulations, to establish zonings for the various aquaculture activities as has been done for some states;
- Adopting aquaculture systems and management techniques that are environmentally friendly and which will promote sustainable aquaculture development of natural resources;
- Enhancing the use of biological techniques rather than chemicals in aquaculture.
There is a need for aquaculture to be recognised as an emerging
sustainable industry of value to the community that is likely to increase in
size and value with time. As such, the industry should seek that planning and
regulatory processes promote not inhibit its future development. At the
same time, the industry should develop and enforce its own code of practices
for environmental protection and conflict amelioration and mitigation. Research in future should emphasise
development of technologies that are environmentally friendly and that provide
equitable social benefits. Sustainability should characterise every culture
system that is developed.
SCOPE AND POTENTIAL FOR FURTHER
DEVELOPMENT
There
is considerable potential for further expansion and development of aquaculture
in Malaysia, both in terms of available resources and supporting infrastructure
and services. Aquaculture is being accorded due recognition by the government
and has been identified as one of the thrust areas for development under the
New Agricultural Policy (1991-2010). By year 2010, aquaculture production is
projected to reach about 200,000 tons and contribute about 15% to the total
fish production annually. Shrimp culture and fish culture are expected to be
the main areas of growth. Although cockle culture is still expected to be
dominant, its percentage contribution is projected to decrease from 70% to
about 20%. Rapid growth of oyster culture is foreseen.
The
strategies for aquaculture development include:
Development
of new sites for the various culture systems
Availability
of potential sites for aquaculture is well recognized. Efforts are now being
made to identify and map these areas for future planning, especially in the
formulation and subsequent alienation of 'Aquaculture Development Areas' (Tan,
in press). Mapping is done through remote sensing and geographical information
systems. One of the setbacks in the past has been the indiscriminate alienation
of land, sometimes in conflict with the interests of aquaculture, and resulting
in low success rates and discouragement in the industry. Through zoning,
further development and better management of aquaculture will be facilitated. Construction
of dams for various purposes in recent years has presented a vast resource for
freshwater aquaculture. Most of the reservoirs (total surface area about
100,000 hectares) are not optimally used for fish production. Present
government policy encourages the use of marginal agricultural lands near the
coasts for brackishwater pond culture. Research is also conducted to develop
cage culture systems in more exposed coastal waters and cockle culture in
deeper waters.
Development
of new culture systems and species
Malaysia has vast untapped ichthyofaunal resource. Research is needed to
identify potential species for exploitation by the aquaculture industry.
Introduction of new species adds impetus to aquaculture development. Demand for
new varieties is very acute
in the ornamental fish industry. Priority is being given to the indigenous
riverine species such as Tor tambroides, Probarbus julleini, and Mystus
nemurus. Marine and
brackishwater species such as the seaweed Gracilaria sp., sea cucumber
Stichopus variegatus, golden pomfret Trachinotus blochii, and abalone Haliotis
sp. have been identified for further research. In addition, research is being
initiated on the application of biotechnological and genetic principles in the
improvement of cultured species. Such efforts include production of
gynogenetic, polyploid, sex-reversed, and transgenic fishes.
Refinement
of present technologies
Efforts
are also focused on the refinement of present hatchery and grow-out
technologies to make them more efficient and cost-effective. Among the objects
of research are the hatchery technologies for marine fishes, oysters, and
mudcrab, and culture technologies for mudcrab, white 133 Downloaded by
[122.55.1.77] from http://repository.seafdec.org.ph on November 26, 2016 at
11:18 PM CST ADSEA '94 Proceedings shrimp, and the freshwater prawn. Further
research is also needed for the development of artificial feed for marine
fishes, biomanipulation of culture ponds, and handling and post-harvest
technologies.
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