FISH DIETS AND THE CONTROL OF EUTROPHICATION RESULTING FROM AQUACULTURE

Eutrophication of water bodies is an important environmental issue rel ated to aquaculture. Strategies for minimising the impact of aquacultu re on the environment include manipulation of mulations and selection of raw materials, husbandry practices related to the feeding of fish, effluent water treatment, recovery of uneaten feed and dead fish, and farm site selection. Concerns about the impact of aquaculture on the e nvironment: have led to the introduction of legislation in a number of countries, and such legislation is likely to become increasingly impo rtant in regulating the aquaculture industry. Whilst legislation on fi sh diet. composition represents one possible regulatory mechanism, suc h an approach must consider the complexities of fish biology and nutri tional requirements, and the many limnological, hydrographic and envir onmental factors which ultimately determine the degree of eutrophicati on. This paper discusses some aspects of fish nutrition and husbandry practices which determine dietary nutrient losses, and considers some aspects and implications of legislation related to diet composition an d feed usage.