With every click of the camera the salmon performed a different acrobatic show: leaping first in high flashing arcs through the air as a warm-up, then working their way up to an impressively swift charge through the dark Atlantic water.

I imagined that this was a display of welcome for me as I arrived at an organic salmon farm on Clare Island, in Clew Bay, off the west coast of Ireland. In fact, I discovered later, rather than being a sign of their appreciation, this is what salmon do all day, every day. Atlantic salmon are just naturally sprightly; their very name, Salmo salar, comes partly from the Latin word meaning to leap.

Farmed salmon have been given a rough ride in the media in recent months. The fish is well- known as a source of essential omega-3 fatty acids and other nutrients but, last January, people were put off eating the fish by a study that compared various toxins in farmed and wild fish and by reports that farmed fish contained high levels of contaminants.

The key word in describing the Clare Island farm, though, is organic. The salmon are raised in the cold waters of the Atlantic. They can jump to their hearts’ delight in the huge cages which are the only things keeping them from disappearing into the deep blue yonder.

And compared with conventional salmon farming, where there is 20-30kg (44-66lb) of salmon per tonne of water, Clare Island, in Co Mayo, has a mere 5kg — less than the organic standard in Ireland and the UK, which is 10kg of fish per tonne of water.

The regime also forbids the use of antibiotics and pesticides, and natural remedies are always tried first. In fact, the salmon are occasionally fed a blend of garlic and rosemary by way of a health boost and to fight off any infection. It doesn’t hurt the way they taste either.

In the interest of fish welfare, more modern medical treatments are sometimes used but the salmon are tested vigorously afterwards to ensure that there is no residue in the flesh.

The farm is said to be situated at one of the most exposed sites in the world — it sits in the middle of open Atlantic with waves of up to 7m (23ft) and an average winter swell of 5m.

David Baird, the managing director of Clare Island Seafarms, who runs the place, says: “There is nothing between us and the east coast of the United States.”

The strong Atlantic currents in this part of the ocean mean that the salmon swim an average of 20km (12½ miles) each day in cages that measure between 10,000 and 20,000 cubic metres (350,000 to 700,000 cubic feet). As a result, what ends up on our plates is a leaner, less fatty piece of fish — which is healthier for us.

In many cases the scare stories in the media about toxins in farmed fish may prove exaggerated. The substances referred to were mainly polychlorinated biphenyls (PCBs) and dioxins. PCBs are now banned in the UK but were once used as coolants and lubricants in electrical equipment. Dioxins are by-products of industrial incineration.

Once these chemicals seep into the environment, animals and fish absorb them into their systems, accumulating the compounds in their body fat. So this means that all foods, not just salmon, contain a certain level of these toxins but some nutritional experts argue that our bodies can deal with these chemicals, in moderation.

Jane Clarke, the Times nutritionist, says: “There is a downside to any food if you look hard enough. However, although organic salmon will have traces of these chemicals — as will all types of salmon — the organic farmers have to be more vigilant about other pollutants from different sources. Of all farmed salmon, organic is definitely the best one to go for.”

Further down the coast into Co Galway is the wonderfully wild region of Connemara, a breathtakingly dramatic patchwork of windswept mountains, desolate valleys, glassy lakes and windy roads weaving through the vast clumps of bracken and peaty bogs.

Graham Roberts, of the Connemara Smokehouse, in Ballyconneely, is one of the few remaining specialists in the British Isles in making smoked wild salmon and he hand-fillets each fish himself to ensure quality control.

He admits that the catch rates are low but says that his fish are unequalled in taste. “In moderation, there’s nothing wrong with eating farmed salmon but, to my mind, wild has a much superior taste and texture,” he says.

Declan Droney, of Kinvara Smoked Salmon, who buys all his fish from Clare Island, agrees wholeheartedly, but feels that the days are numbered for wild salmon. “Yes, you can still catch wild salmon, but it is far better to conserve what little we have than to face a near-extinction of the species in years to come. Organic is as close as you can get to wild and what Clare Island offers is near perfect,” he says.

MAKE THE MOST OF A GOOD CATCH

In Kinvara, Declan Droney’s smokehouse employs traditional smoking techniques to produce smoked organic salmon reared at Clare Island. Available in the UK through Waitrose and Fresh and Wild stores, or by mail order (www.kinvarasmokedsalmon.com; 00 353 916 37489).

Times recommends

• Live chat: Thrifty ways to update your winter wardrobe
• Is anybody out there really listening?
• Nutrition Q&A: Will eating late make me fat?