Farming fish in open water potentially could have an effect on the local environment, changing the pattern and number and species of plants, animals and microorganisms — the biodiversity — in the immediate vicinity.
This could be the result of feed waste and faeces, escapes and disease transfer. Additionally, fish farms are subject to attack from predators. Attracting predators and controlling predators are factors in biodiversity.
Changes in biodiversity around Marine Harvest activities can help indicate the extent to which individual sites are meeting the objective of minimising environmental impact.