Scientific Congress Presentation
THE ENVIRONMENTAL IMPACTS OF MARINE FISH CAGE FARMS IN THE EASTERN ADRIATIC
2003, 61 (4) p. 175-194
Abstract
Mariculture in Croatia could play a more important role in development of rural communities along coastline. However, by increase of fish farming, public concern over environmental issues has been raised, and the need for more responsible mariculture development and management has been asked. There are opportunities and challenges for effectively integrating mariculture into coastal zone management with equal rights and obligations. This is primarily because of its social and economic mission consisting in preventing de-population of rural coastal areas and islands and meeting the growing needs of tourist market for seafood. Although intensive mariculture production is accused of producing negative environmental effects, many of these effects still need to be scientifically documented. The effect of nitrogen and phosphorous releases from farmed fish faeces or uneaten food is not of significant issues for marine ecosystem, and it is generally of little importance compared to the inflow of nutrients from other coastal sources. The impact on sediment and benthic communities is mainly local and short-term ones, and depends on the number and extent of the farms and their location. Recovery of some benthic communities after the cessation of farming activities may be delayed over several years (i. e. Posidonia beds) due to the accumulated organic matter. Bluefin tuna farming if not properly located and managed might cause pollution problems, either from uneaten feed and metabolic waste or from harvesting and processing the fish. In most cases the problem comes from smell pollution during the summer time and the oily water surface that may be widespread much outside of the farm areas. It will be important for sustainable development of Croatian mariculture to offer a healthy and good quality product in the quantities required by the market, while not degrading the marine environment.
Keywords
mariculture, cage fish farming, environmental impacts, ecological changes, biological response