1.1 The origins, emergence and development of aquaculture

Mankind from very early times has practiced various forms of aquaculture with different fish and shellfish species. Just as humans sought to domesticate terrestrial animals and plants through agriculture, there were similar but less extensive efforts with fish and shellfish. In many cases, these aquaculture practices involved simply capturing small fish and keeping them in enclosed ponds or lagoons. The juvenile fish came from wild stocks and much of the necessary food came directly from natural sources.                                                                                                           Early examples of aquaculture in Europe would include, early shellfish farming where small oysters were held on the shoreline until they reached an edible size or, in the case of fish, the keeping of carp in millponds as a ready source of fresh fish. Similar practices continue even up to present times with, for example, the clam industry in Portugal where young clams from the wild are maintained in protected areas until ready for harvest.

In later centuries, however, as man began to understand the complex biological processes involved in the life histories of various species, it became apparent that these natural processes could be manipulated, particularly in the case of freshwater fish such as trout and carp. Thus, employing basic breeding techniques gave consistent supplies of juveniles and through developing external feed sources it was possible to yield a steady stream of produce. Whilst these practices were widespread, they were generally on a small scale. It was only in the latter half of the twentieth Century that modern 'intensive' aquaculture emerged and, only in the last two decades, has it become a significant commercial venture. Intensive fish farming has now developed to such a scale that it makes a significant contribution to many national economies and it is an important economic activity in the remote coastal regions of Europe.