As one of our class’s representatives of aquaculture stakeholders, I am here to tell you about the many advantages provided by aquaculture. First of all, aquaculture in Australia employs around 5000 people according to a report by the Australian Bureau of Statistics. The same report also states that aquaculture can be used to re-establish endangered and threatened species in depleted fisheries, as well as in depleted reefs. Aquaculture provides a unique opportunity for researchers to closely monitor native fish species, and this research also contributes to better stewardship of the reef. Many people have expressed concerns over the nutrients released in aquaculture, through both feeding and fish excrement. However, prawn farming makes up a considerable portion of aquaculture in Australia, and studies by the Australian Prawn Farmers Association provided the following statistics:
The largest anthropogenic source of Nitrogen to Queensland east coast rivers is that associated with sediment loss from grazing which is estimated at 18,018 tonnes per year (55.78% of the total anthropogenic input). Other sources are 8,800 tonnes per year (27.24%) from canelands, 3,502 tonnes per year (10.84%) from fertiliser applied to agricultural land other canelands, and 1,928 tonnes per year (5.97%) from sewage. Inputs of Nitrogen to the Queensland east coast from prawn farming are estimated at 52.6 tonnes per year which is 0.1% of the annual anthropogenic Nitrogen input to Queensland east coast rivers.
The largest anthropogenic source of Phosphorous to Queensland east coast rivers is that associated with sediment loss from grazing which is estimated at 5,544 tonnes per year (65.02% of the total anthropogenic input). Other sources are 1,300 tonnes per year (15.25%) from canelands, 878.1 tonnes per year (10.30%) from fertiliser applied to agricultural land other canelands, and 1,928 tonnes per year (9.36%) from sewage. Inputs of Phosphorous to the marine system from prawn farming are estimated at 6.6 tonnes per year which is 0.00006% of the anthropogenic P inputs to Queensland east coast rivers.
Since European settlement, sediment input to Great Barrier Reef catchments has increased 3.8 times to 28 Megatonnes per year. Sediment input from prawn farming contributes 1,314 tonnes per year or approximately 0.0004% of the annual anthropogenic sediment input to Great Barrier Reef catchments.
As these numbers illustrate, the environmental damage being done by aquaculture pales in comparison to that done by terrestrial farming. And because the fish produced by aquaculture decreases the amount of food terrestrial farms need to produce, they may even help avoid nutrient pollution near the reef. Besides, the aquaculture industry could not cause massive pollution to the Great Barrier Reef even if it wanted to. According to the Queensland Aquaculture Industries Federation Inc, “All aquaculture in Queensland is closely regulated to reduce environmental impacts.” As you can see, aquaculture is part of the solution to environmental threats in the Great Barrier Reef. So why not use aquaculture?!?!
Links:
http://www.apfa.com.au/environment/world-leaders-in-sustainable-prawn-farming/
http://www.aquaculturequeensland.com/about/environment.html
http://upload.wikimedia.org/wikipedia/commons/c/cd/Penaeus_esculentus-2009.jpg