Mr A. Xuereb (The Sunday Times, September 26) has every right to be worried (as should we all!) about the "large, voracious species of fish" that is attracted to fish farms: and he is spot on in his assertion that this is a Great White shark.

In 2000, while watching Sky TV in London, I was taken aback by a documentary on the Great White in the Mediterranean, with film footage of an attack on a woman swimming in Italy. I had read about the huge Great White caught in Maltese waters some years back.

It is true to say that in my 65 years, I know of only one shark attack in Malta - the tragic one in St Thomas Bay, but then, fish farms are a relatively recent introduction.

Those interested in marine biology, however, and who have read or studied about this great killing and eating machine, know that apart from seals, tuna is its natural food. The incident off Libya mentioned by Mr Xuereb emphasises this point.

When I returned to Malta recently and saw the numerous fish pens so close to shore, and especially close to bathing areas, my immediate reaction was - did the authority concerned seek the views of marine experts before granting licences?

A couple of weeks ago, while discussing this issue with a police officer, he told me that a friend of his, who dives to check the pens, had seen sharks in the vicinity of the nets.

The whole situation reminds me of the film Jaws, where, after a Great White had killed a swimmer, the mayor of Amity forbade the police chief from closing down the beaches in the holiday resort to safeguard the 'tourist business'.

I believe the government wants to move all fish farms to one site to the southeast of Malta... hopefully way out to sea, far away from bathing areas. So why the delay in implementing it?

Or are they, like the mayor of Amity, waiting for a disaster to happen before action is taken?