The article entitled Maltese Fish Stocks 'At Risk' (January 4) is rather sensational. Actually the risk of introducing new exotic viruses is not as big as some institutions would want us to believe. What we are speaking of is just a possibility and this possibility of introducing new fish diseases through imported bait used in tuna farming is definitely not the only avenue or the biggest avenue of introducing new pathogens into an area.

The transfer of new species through ballast water is a well-known phenomenon and, in fact, we have registered new species in the Mediterranean originating both from the Red Sea and the Atlantic Ocean. Other bigger avenues of introducing pathogens into an area also exist through the vast amounts of untreated sewage that ends up directly into the Mediterranean from all the shores of the surrounding coastal states.

Tuna penning in the Mediterranean is now almost 10 years old and to date there have been no reports of mass deaths of wild stocks as the WWF report wishes to indicate. We agree with EU Commissioner Joe Borg and the position taken by the European Commission that any drastic decision on the ban of the use of bait fish originating from other seas in the tuna farming operations in the Mediterranean would have drastic economic effects that would threaten the livelihood of a great number of farm operators and fishermen. It was the tuna farming practice that revived the tuna fishing sector.

Tuna farming in the Mediterranean takes place in nine different coastal states and all operations import bait fish from other areas. Limiting the use of bait fish to small pelagics from the Mediterranean would drastically effect the Mediterranean ecosystem because the uptake of small pelagics would increase. This in itself is a clear indication that the suggestion by WWF to limit the use of bait fish to a Mediterranean origin is an unsustainable situation for the Mediterranean fishermen involved directly in small pelagic fisheries and to other fishermen indirectly.

Last but not least, blue fin tuna is a highly migratory fish and every year travels to the Atlantic and back. It feeds along the way on small pelagics coming from all the areas it migrates through and may well be acting as a virus carrier when it returns to the Mediterranean every spring!