Tuna penning - and the huge, voracious fish!

I read the comprehensive letter (The Sunday Times, September 12) by Dr Joseph Carabott Damato, MD, under the title of "Amateur fishermen oppose tuna farming in the south".

All parts of this letter are interesting, but for me the most lucid paragraph is when he said: "Fish farms are also an attraction to large, voracious species, which are so encouraged to concentrate in that area and, while detrimental to the endemic fauna, certain species can be harmful to humans."

In fact what is this large and massive, voracious fish? From June 12 to 15, 2002, a large white shark (four to five metres long) entered a tuna pen and stayed in it for four days before escaping. This occurred about 140 km north of Tripoli, Libya.

The presence of tuna pens off Marsascala is found to attract large, voracious fish - foremost among these is the white shark, for which the bluefin tuna - Thunnus thynnus - represents the main natural diet.

Meanwhile, frequently a large quantity of tuna blood and other fluids are dumped in the sea at Xrobb l-Ghagin, Delimara, when the tuna is processed and ready for export.

Tuna are killed in the water and bleed heavily. In fact, a large area around the pen will be red dirt with tuna blood and guts... the equivalent of "chumming" that attract large, voracious fish, and which is this large voracious fish?

If tuna pens continue to be installed close to shore - surely it is a simple case of lack of knowledge and expertise - and the risk will continue to worry anybody. Perhaps the authorities (MEPA) ought to consider issuing permits to instal tuna pens only if these are situated several kilometres off the shorelines of the southeast of Malta, possibly on the Hurd bank zone and not off Zonqor Point, as we read recently!

Meanwhile the exploitation of the blue fin tuna is regulated by ICCAT, the International Commission for Conservation of Atlantic Tunas, that Malta became a contracting party of in 2003.