While we congratulate Neil Agius on his incredible feat of setting yet another endurance-swim record, his stated aim of raising public awareness of serious ecological problems associated with pollution and pollutants in Maltese waters was unfortunately misdirected.

By far, the main issue in Maltese waters is not about old tyres dumped in the sea for convenience or the odd lump of scrap metal chucked into the water by selfish people too ignorant to do the right thing.

While those irresponsible actions are bad enough, other exponentially larger issues and significantly more harmful sources of crippling pollution are being not just ignored but protected by powerful political patronage, and in fact encouraged to grow and become more prevalent.

I refer to the tuna ranches dotted around the island. Aquaculture is a lucrative enterprise for those invested in it. It grows by around five per cent annually and profits are steadily increasing year by year.

In aquaculture, by far the most harmful ecologically, environmentally and from a sustainability point of view, is tuna ranching, erroneously known as tuna farming in Malta.

Fish farming is about the breeding of fish species in tanks and growing new stocks from fish eggs. Ranching is about trapping wild stocks indiscriminately to near extinction and fattening stock in small and intensively cramped pens, often with steroid and antibiotic-rich feed.

Tuna ranching can be compared to the intensive agistment of pigs in confined spaces through the use of a uniquely valuable resource owned by all citizens of Malta, and not just by the chosen few who are granted licence to savagely exploit a very limited and valuable natural resource by a benign government.

Our most valuable natural asset is the glittering Mediterranean and it deserves protection. The operators of tuna farms in Malta are too politically powerful and seemingly immune from strict regulation; so nothing too dramatic is likely to happen to their licences.

Applications to extend their operations have been routinely granted, demands to move their locations to more protected waters at the risk of serious health issues to coastal habitation have been met with alacrity.

There must be serious rethinking of these policies by regulators and governments. Tuna ranching in Maltese waters is economically, socially and environmentally unsustainable. And these days, unacceptable.

Malta’s economic main anchor is tourism. Tourism is the economic engine room of this nation. We can wax lyrical about our rich history but, generally, tourists come to Malta largely during the warmer months primarily for the dazzling blue waters which embrace our land.

Any environmental threat to that is a threat to Malta’s economy. What is called tuna farming is a significant threat to our once-pristine waters.

In aquaculture, by far the most harmful is tuna ranching- Anthony Trevisan

The contaminants arising out of intensive tuna farming are serious threats to the health of the marine environment and communities. Tens of tons (some experts say hundreds of tons) of excess uneaten feed settles on the sea floor together with the accumulation of hundreds of tons of faeces effluent from the large animals in enclosed pens, piling up on the seabed as a highly toxic waste of pollutants including high antibiotic residues, food supplements, growth hormones as biostimulants, nutraceuticals… the list is long.

Communities, particularly coastal communities who live under the influence of these biohazard factories, are seriously exposed to health risks. Swimming in close quarters, fishing and eating fish exposed to these mountains of toxic waste are without doubt highly risky.

Sustainability is a joke to tuna ranchers. Tuna farmers breed the tuna. Tuna ranchers mercilessly trap and exploit huge shoals of migrating juvenile tuna in Eastern Mediterranean waters and drag their netted catches to pens where the fish are fattened for sale and export. This practice has almost wiped out naturally occurring stocks of tuna.

The industry is riddled with fraud, unreported catches and unregulated overfishing.

In Turkey, where the industry is much better controlled, tuna ranching is being replaced with tuna farming. In other words, the exploitation of wild stocks to near extinction will be replaced by breeding the species in land-based tanks and growing them to a suitable, marketable size. This is like salmon is farmed in many places.

Successive Maltese governments of the last two decades have fuelled the rocket engines of the Maltese economy through construction and development. This historic land of ours, once blessed with stunning architecture influenced by various historic rulers, has had its prized heritage bulldozed into oblivion and its honey-coloured stone replaced by the grey of a concrete jungle.

We now live in one of the most polluted air environments in Europe with rising counts of dangerous particles in the air we breathe. The only natural asset left to us is our azure sea.

Regulators, please don’t screw that up too.

Anthony Trevisan is a Maltese-Australian entrepreneur and philanthropist.