What is Aquaculture ?
The term Aquaculture covers all activities aimed at producing,
processing and marketing aquatic animals and plants from fresh,
brackish and salt waters. In narrow terms aquaculture embraces
the use and manipulation of natural and artificial bodies of waters
to produce species of fish required for human consumption and thus
concerns all activities associated with breeding and culture of
aquatic organisms.
Aquaculture is an exciting and complex discipline that is at once
an ancient art and yet a pioneering science. It is proving to be
one of the best strategies for fulfilling the world's growing food
needs.
the
science of aquaculture
key
benefits of aquaculture
hatching,
farming, harvesting & processing
aquaculture links
The Science of Aquaculture
Aquaculture
is the art, science, and business of producing aquatic plants and animals for
human use in a controlled environment. Due to our highly health conscious
society and the declining wild fish populations, there is a need is increasingly
felt for development of aquaculture sector virtually around the world. The same
is evidenced by phenomenal growth the sector has experienced In the last decade.
The role aquaculture will play is to aid in producing reliable, high quality
protein containing products such as fish, shellfish and plants for the consumers.
Aquaculture, like agriculture, is the cultivation and harvest of
plants and animals for human use. Both are farming, but aquaculture
- farming in water - requires a different set of knowledge, skills
and technology. Plants and animals are held in water in a variety
of systems, fed continuously, harvested and sold to distributors.
Fish farming is rapidly expanding all over the world. Wide ranges
of species are being grown internationally and this is helping preserve
and sustain wild fisheries.
Environmental
Conditions
Aquaculture is totally dependent on the quantity and quality of water available.
As a result, the first consideration in the process of developing an aquaculture
system is to study a source of water. The water generally has to undergo a thorough
chemical analysis prior to being employed in such a project to ensure it is
low in chemicals such as arsenic, boron, fluoride and other elements, which
could be harmful to the survival of aquatic organisms.
Aquaculture Systems
Aquaculture occurs in three different forms: ponds, pens, and recirculating
tanks. Pond aquaculture is most like farming. With this method,
areas of land are enclosed by dikes and flooded. Fish, most commonly
catfish or shrimp, are then added to the pond. The fish or shellfish
are fed on a regular schedule, and a clean source of water is used
to keep the pond in the proper condition for healthy growth.
Floating pens are the most common methods for growing marine finfish,
such as salmon, in protected coastal waters. One of the biggest
concerns in aquaculture is continuously providing fresh, clean water
for the fish. In large enclosures made of netting, fish can enjoy
a natural flow of water and all the food they can eat. This open-water
approach is also used in growing marine shellfish, with the natural
currents bringing both clean water and plenty of food for filter-feeding
bivalves such as oysters, quahogs, and scallops.
The
newest kind of aquaculture employs recirculation systems to clean and re-use
water. "Recirc" systems are made up of several components that filter
the culture water of waste and toxins as well as treating it reduces bacteria
and viruses load. Because one can control the environmental parameters in this
recycling system, it allows growers to carefully control water quality and eliminates
them from the risk of weather-dependent ponds and pens. Recirculating systems
also use far less water than other methods and any discharge water can be thoroughly
treated to make sure that no waste is released into public waters.
Types of Aquaculture
Depending
on the requirements of the species, the animals or plants can be raised in a
warm, cold or marine environment. In warm fresh water, catfish, crayfish, baitfish,
sportfish, tilapia and ornamental fish are grown.
Cold fresh water trout and salmon are grown. In mariculture, which uses brackish
or salt water, brackish clams, oysters, seaweed, mussels, shrimp, haddock, cod,
salmon, and flounder are grown.
Each life stage of these species can take place in several different growing
environments. Depending on the species being cultured as well as the location
of the facility ponds, tanks, open ocean, raceways, or cages would be choices
for rearing systems.
Key Benefits of Aquaculture
- Production of healthy harvests in pollution free environments
- Quantity and quality control of species and distribution
- Defined species management - no wastage or bycatch
- Potential to meet increasing market demands
- Strong financial benefits from rising prices and diminishing
supplies
- Alternative source of supply for overfished, high value species
- Minimal impact on the environment
- On land or sea cage options
- Accessible Global expertise and research resources.
Hatching, Farming, Harvesting and Processing
Once the water source and systems are in place, the water is 'fertilised'
with algae to create a natural environment for the growth of fish
and other organisms. The production process starts with the stripping
(artificial spawning) of female fish. Eggs are fertilised with milt
from selected males. The fertilised eggs are placed in the hatchery
under careful supervision.
Hatching
of eggs is the next stage. The fry emerges from the egg with a large yolk sac
on its stomach. The yolk functions as nutrition for the first few weeks, after
which the first careful feeding begins. At an age of approximately 12 to 18
months, the fish has developed into a smolt, and is ready to be placed in the
sea.
Fish
spend one to two years in sea cages. When the fish are released into the sea,
the production of table fish has started. During this growth phase, the fish
farmer monitors the fish carefully and adjusts the quantity and quality of feed
in line with water temperature and other biological conditions.
At an age of two to three years, the fish are harvested after having reached
sizes demanded in the markets. The fish are prepared for sale in special processing
plants.
High quality fish, graded 'superior' are now ready to be freighted
in special packaging to importers in a number of countries. Thanks
to modern-day transport amenities, harvested fish reach their consumers
at the most three days after being harvested.
Aquaculture Links
www. AquaText.com
- Aquaculture dictionary
www. AquaFeed.com
- Aquafeed industry site
www.
Aquamag.com - Industry-related publications