Simply Putting on Weight

Some of the oldest laws​ in Britain were drafted in defence of the Atlantic salmon; one of the lesser-known clauses of the first Magna Carta in 1215 ordered the removal of all salmon weirs in the Thames and Medway estuaries, a statute that remained in force until the end of the 19th century. In Scotland, there is still no public right to fish for salmon, even in the sea, while recent bylaws passed in England and Wales have reinstated a number of ancient restrictions, including on the use of the ‘Viking’ haaf nets that have been a feature of Cumbrian salmon fishing for more than a thousand years. Native American, Norse and Celtic myth-makers wove the figure of the wise or noble salmon into a number of early myths and legends, such as the sixth-century Welsh quest narrative of Culhwch and Olwen collected in The Mabinogion, in which a sea-scarred, Severn-born salmon is revered as the oldest and wisest creature on earth; or the Ossianic legend of the Salmon of Wisdom, the skin of which was accidentally eaten by Fionn mac Cumhaill, who from it gained oracular access to all the knowledge of the world.

Salmon – the name, it’s thought, derives from the Latin salire, ‘to leap’ – has always been a fish apart, marked by its unusual capacity to migrate between the distinct worlds of salt and fresh water. According to William Camden’s Britannia (1586), the salmon leaps of Pembrokeshire were Britain’s first tourist attractions, at which scores of people would gather to ‘stand and wonder at the strength and sleight by which they see the Salmon get out of the Sea into the said River’. The spectacle remains one of the great sights of autumn, and people still crowd the banks of the Teifi to watch the returning salmon launch themselves at the cascading waters in brute determination to reach their ancestral spawning grounds upstream. Many don’t make it, but for those that do, it marks the end of an extraordinary circular migration that begins and ends in the same shallow gravel-beds to which every sea-run adult will seek to return at least once in its life: an impulse that was confirmed by Francis Bacon in the 1620s, when he tied ‘a Ribband or some known tape or thred’ around the tail of a sea-bound smolt, retrieving it the following year when the fish returned as a splendid silver grilse.

‘Smolt’, ‘grilse’: as Richard Shelton observes, salmon are spoken of in a ‘stained-glass language’ of their own, their life stages marked by an ichthyological lexicon unchanged since Chaucer’s time. Born in a ‘redd’, a shallow, gravel-covered depression dug by the female in the days before spawning, newly hatched salmon begin life as ‘alevins’, tiny, buoyant creatures with their yolk sacs still attached. Once the yolk has been absorbed, the fast-growing fish, now known as ‘fry’, are able to feed for themselves, turning instinctively to face the current in order to graze on drifting insect larvae. Some months later, the juvenile salmon, now known as ‘parr’, move downstream to deeper water, where their markings grow darker and their shapes more distinctively salmonoid. By the following spring, most parr have begun the first of the transformations that will enable them to cross the hydrological boundary from the river to the sea: once their kidneys have been primed to reverse their usual function of taking in salts and excreting dilute river water, their skin colour brightens to reflective silver through a microscopic coating of guanine crystals, and their body shapes fill out in anticipation of the long voyage ahead. It is then that the ‘smolts’, as the fish are now known, are ready to head downriver to the sea.

Once out in the ocean, the salmon are lost to view. By day, they swim too near the surface for a ship’s sonar to distinguish them from the acoustic ‘clutter’ created by waves, and at night, when they descend, their shoaled shadows seem to disappear. It is only in recent years that fisheries scientists such as Shelton have succeeded in tracking the oceanic wanderings of spring smolts – or rather, ‘post-smolts’, now that they have left the river. As soon as they reach the sea, it appears, Atlantic salmon (unlike their shore-hugging relatives, the sea trout) head rapidly away from the coast, crossing a series of sharp salinity and temperature contours in what appears to be a headlong journey north, towards the plankton-rich feeding grounds of the Norwegian Sea.

The phytoplanktonic bloom, which covers much of the North Atlantic in microscopic algae every spring, is the most important event in the global marine system, a vast green banquet that attracts much of the world’s zooplankton, the tiny free-swimming animals on which the rest of the oceanic food web depends. For a few months, as millions of tonnes of nutrients transform the top few metres of the North Atlantic into a kind of concentrated chowder, shoals of long-distance predators make their way to the feast, their migrations assisted by the same north-trending currents that stir up the oceanic broth while preventing its dispersal. Young salmon, from rivers on both sides of the Atlantic, arrive in their tens of thousands to gorge themselves on krill, sand eels and arctic squid, their bodies growing fast compared to those of most other sea fish, from the few ounces they weighed on leaving home, to three pounds or more by the end of the summer, and eight or even ten pounds by the end of the following year. Some of these fattened one-winter salmon, now known as ‘grilse’, will begin to make their way back to the redds of their birth, drawn by the scent of familiar waters that was imprinted on their sensory systems during the outbound stage of the journey. The others will remain at sea for another year or two, sometimes even three, before they too turn home, transported, as though under a spell, back to their ancestral rivers, and up the series of perilous and exhausting leaps that gave Salmo salar its name.

To Sea and Back is a remarkable book, a lyrical zoography of the Atlantic salmon that weaves in and out of a wider historical narrative of ocean exploration, fisheries science and personal memoir. Admirers of Shelton’s previous book, The Longshoreman: A Life at the Water’s Edge (2004), will be familiar with the loose structure (as well as with – it must be said – a fair amount of recycled material), but the controlled meanderings that marked out The Longshoreman as a new kind of nature writing range further afield in this second outing, in which the motifs of exile and homecoming are refracted through a series of autobiographical asides that evidently made a strong impression on whoever wrote the press release, since it gave the title as To Sea and Back: The Heroic Life of the Atlantic Shelton, an insightful slip, given that much of the interest of the book derives from untangling the complex relationship between the author’s knowledge of the sea and the personal circumstances that first drew him to it.

It was, he says, the chalk streams of the Chilterns that made him ‘first a naturalist and then a biologist’, encouraged by the books he discovered in his grandparents’ library, a room overshadowed by the menacing horns of long-dead Highland cattle. Frank Buckland’s multi-volume Curiosities of Natural History (1857-72) held a particular fascination for him – ‘I have the four little books in front of me now and, opening the first of them, it falls open at the chapter on rats that was my favourite holiday reading of over half a century ago.’ Ah, yes, Frank Buckland and his edible rats. As a would-be social reformer and committed zoophagist – an eater of unusual animals – Buckland was convinced of the double benefits of putting rat meat on the national menu: not only would it help relieve the hunger of the poor, it would also ease the infestations that plagued every city in the world. ‘It is not generally known what good eating young rats are,’ he wrote, with a lack of squeamishness inherited from his father, the Very Rev. William Buckland, dean of Westminster, who regularly plied his dinner guests with dog, panther, crocodile and hedgehog, as well as with canapés of toasted field-mice (a favourite of Frank’s). Although the failure of his rat meat campaign was followed by other attempts to amend the eating habits of the poor – ‘in my humble opinion, hippophagy has not the slightest chance of success in this country,’ he wrote after a disastrous dinner in which every dish, from the soup to the jelly, had been prepared from the carcass of a knackered old cab horse – it was in his role of inspector of salmon fisheries, to which he was appointed by the Home Office in 1867, that Frank Buckland finally made his mark on the British diet by introducing stockbreeding methods to the rearing of salmon and trout. His aim was twofold: to increase domestic fish supplies while introducing fast-growing freshwater species to the newest territories of the British Empire, New Zealand and Tasmania. Trays of ice-cooled ova were shipped across the world to be released into the southern hemisphere’s most pristine rivers, but while the European trout species established themselves well, the Atlantic salmon failed utterly, their genetic predisposition to head north to colder waters proving lethally unsuited to the warm, shark-patrolled expanses of the South Pacific.

At home, meanwhile, Buckland was becoming quite the showman, touring a miniature salmon hatchery around the country, while campaigning for the cleaning up of industrially polluted rivers from which ‘the king of fish’ had virtually disappeared. Buckland’s claim to have met the elderly man who caught and ate the last salmon in the Thames seems about as likely as his father’s claim to have eaten the desiccated heart of Louis XIV (‘I have eaten many strange things, but have never eaten the heart of a king before’), but his outrage at the poisoning of British rivers was authentic, and his published findings did much to change the views of politicians and industrialists, though probably not of the factory owner who assured him that ‘sulphuric acid was a tonic for the fish.’ But however gratified Buckland might have been ‘to hear again of salmon in the Kelvin, Clyde, Tyne and Thames’, he left another legacy in the form of modern high density fish farming, the greasy-fleshed results of which, Shelton rightly complains, ‘bear little culinary relation to their wild-caught counterparts. The flavour tends towards the uriniferous with lower notes of stale fish food.’ Even Shelton’s terrier, Dinah, ‘an otherwise enthusiastic little scavenger of generally catholic tastes’, refuses to touch it, though the Bucklands would probably have wolfed it down raw.

Most farmed salmon tastes horrible because caged fish have no opportunity for active swimming. Fed on high-fat pellets full of artificial colour – the pinkness of a wild salmon’s flesh comes from the amphipods and krill it eats during its time at sea – the cooped up salmon simply put on weight without distributing the fat around their bodies. A wild sea-run salmon, by contrast, prepares itself for the journey home by storing fat reserves across its muscles, connective tissues and under the skin, from where it will draw the energy to sustain it during the task ahead. As soon as it smells fresh water again, an adult salmon will stop feeding, devoting itself solely to the rigours of the voyage, its body beginning its final transformation, as its immune system shuts down to conserve energy, its skin starts to lose its silvery sheen, and (in the case of the male) a rush of hormones prompts the lower jaw to change shape, curving into an aggressive-looking underbite known as a ‘kype’, a jutting scimitar used for fending off other males in the spawning grounds upstream.

The journey can take many months, however, and as the starving returnees battle against the freshwater currents, their fuel reserves deplete rapidly, consumed by the effort of the journey as well as by the production of eggs (by the females) and milt (by the males), so now they must rely on bursts of adrenalin to scale the near vertical ascents. The physical cost of homecoming is enormous, and those that do make it home to spawn arrive in a terrible state, weak, exhausted and already dying from disease and starvation, so the effort of mating, described by Shelton with an Attenboroughesque attentiveness – ‘the quivering displays of the sailor home from the sea bring the hen to arching orgasm’ – is often their final act. Shelton coolly describes the lingering death of a spawned-out male, now known as a ‘kelt’ – the last of its names – lying in ‘the shallow tail of a pool’, with its arteries blocked and muscles wasted, its broken skin scarred by bacterial infections, as it slowly drowns in the water that seeps into its wounds. The decay that follows serves to replenish the river with phosphates and nutrients that in a few months’ time will help sustain the hatched young that emerge from the redds, buoyant and vulnerable in the shallow water, until they, too, are ready to head downstream on the first stage of ‘their great adventure’, as Shelton calls this vast oceanic circumnavigation that will end, as do all great journeys, in the place it began.