Application
The need to rely only on natural resources in our present day is becoming more dramatic. A
greater need on managing resources and developing techniques are the only answer presently.
The fisheries industries is the topic of this site, and a brief look at man’s effect on the
environment will be examined to see what needs to be done.
Presently, some of the fishing industry are surviving, while others such as Cod, shark, salmon, and
others are endangered not only for the industry, but the species as well. Mans’ demands are
increasing on account of population and wants. As a result, the fishing industry has responded, and a
move away from old techniques has occurred. Techniques in aquaculture such as cage farming has
become a major method of managing demands and keeping fish populations up.
Cage farming in Canada is presently used throughout. Species such as trout, salmon, and attempts
on Cod are being farm with the method. It is a good technique, but does have it draw backs. The
technique is very good for developing large stocks. Another old technique used all over the world
are
land based farms
. These farms are usually more expensive to startup, but can be just as
productive. The difference between the cage farming is that first, a large water source is needed
such as a neighboring body of water(river or lake) or ground water. Secondly, a land gradient is
needed to maintain a cheap flow of water throw the farm. In any fish farm, water quality is an
important factor for the species health and at times there consumption. Poor water quality can
actually have an effect on the taste of fish. Waste in water can exist as solid or dissolved. High
concentrations of pollutant such as Ammonia, nitrates, carbon dioxides can have a varying degree
of affect on each species, and these contaminants can grow quickly in fish basin if water flow or
change doesn’t occur. As a result, the movement of water throw a farm will have an impact on the
farm’s capacity and size. For example, A general rule of thumb for trout is that 4 -5 pounds of
fish(es) can survive in one cubic foot of water. These factor can vary based on factors of water
quality, temperature, flow, and size and type of fish. Another example is the importance of flow on
the demands and stresses on fish. Like any living being, the harder the creature works, the more
food consumption is needed. Secondly, oxygen needs go up as well.
The reason that I am going into such detail is to move into the next stage or development of the
fish farming industry. The creation of cage and flow through land based farms are important moves
to maintain industries and species, but many environmental impacts on these types of farming
practices have occurred. DNA altered fish that survive to higher stresses and growth patterns are
impacting natural stocks in rivers and lakes. This happens when fish escape from the farms. A
second problem is that these farms (especially cage farms) have insufficient or no waste treatment
system. Thus fish waste are contaminating waters down stream, and have an MAJOR impact on
other user in the water shed. Closed loop system have been development with varying results.
These systems are however the most expense, and may only have a future with small stocks. An
example of such a system’s layout can be seen on the opening of this site. While waste controls
are costly and placed on such systems, temperature controls are also needed. There are many
benefits to such systems. They can vary from many external factors such as pollutant and disease
entering a system, predators(otters, seals, birds), major storms, and temperature. The farmer can
also work in better environmental condition in order operate, maintain or repair the system.
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