Following recent claims that culturing salmon in open net pens could become the most sustainable form of healthy protein production on the planet, Dr Bill McGraw assesses the relative merits of different aquaculture species and systems. As a specialist in the culture of shrimp in RASs, the conclusion he draws may not come as a surprise. The sustainability of aquaculture has been debated for decades. Potential issues include habitat destruction, the use of marine ingredients in feeds, freshwater usage, using wild juveniles for farm stocking, influencing wild gene pools through farm escapees, and the excessive loss of stock through disease and associated overuse of antibiotics.
Is there aquaculture available that has all positive attributes? In other words:
Uses lower amounts of fishmeal.
Uses a very small amount of freshwater per weight of product produced.
Has a positive impact on the environment by incorporating all waste from the system into other forms of agriculture.
Has a small footprint with large production per unit area.
Does not promote controversial GMOs.
Has a low FCR.
Does not use juveniles from the wild, or affect wild genetics.
Loses minimal biomass to disease without the use of antibiotics
Is able to provide products 365 days a year.
No contamination from pesticides, herbicides, heavy metals or harmful chemicals
In this article Dr Bill McGraw briefly reviews these challenges, and outline how the impact of different types of aquaculture can differ on each count.