The Salmon: The Extraordinary Story of the King of Fish. Michael Wigan

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СКАЧАТЬ their presence having been determined by ancient geology. Really, they are true and admirable survivors, but it does not feel like that. And their chromatic violence in the drab landscape adds to a sense of displacement.

      In Lake Ontario the early settlers found landlocked salmon weighing up to forty pounds. So much for the sea only being able to build up weight; pike disprove that and the lake salmon underlined it. These monsters, however, are now gone. In Maine the landlubbers are called ‘sebago’, being the name of lake in which they were first identified, and in other Maine lakes there are different varieties of salmon non-migrants.

      To an angler a salmon is in its natural place in a river. That is where an encounter can occur. A river is the proper mis-en-scene for connection with the fish by a wispy length of nylon on a bendy stick, and a hook maybe no bigger than a gnat. What salmon do in rivers is a subject upon which fishermen have ventured opinion in a veritable lexicon of viewpoints. Seldom has so much speculation been focused on one inhabitant of our environment. How many shelves could you fill with the books which have celebrated the mysteries and majesties of moles, rabbits or hedgehogs?

      Long ago debate centred on whether salmon eat in rivers. It seemed impossible that a large creature could enter a river a year before undertaking the rigours of spawning and live off its reserves. Anyway, why did they take fishing flies if they were not eating?

      Peter Malloch, as Scotland’s Inspector of Fisheries, seemed to have nailed the matter way back. He and his team eviscerated thousands of salmon. They never found anything in the stomachs, no matter how long the fish had been in the river. Even if, as happens in a few places, salmon over-winter in a river and do not spawn till late the following year, they still do not feed. It is a stupendous fast. However, it failed to stop many subsequent armchair theorists raising spectres and postulating that salmon must eat, that sundry reasons existed for their stomachs being empty, that what was evident knowledge was as full of holes as a colander. The fact, amazing as it is, remains: salmon cease feeding in freshwater. Like snakes, which can live for months, even years, without eating, salmon subsist on their stored marine reserves. If they open their mouths to seize fishing flies in rivers, fishermen may claim they have been artful enough to override behavioural rules; angler achievement is all the greater. Not quite as great, though, as the biology of their quarry.

      An area for debate between anglers and salmon professionals is whether the leaping salmon is moving upriver or not. So many times ghillies and anglers talk of ‘fish running’, meaning they are ascending the ladder of the river-system. But if you watch salmon from under a river at their level, as is possible in the riverbed salmon museum on Sweden’s River Mörrum, you see that jumping salmon may move slightly forwards from where they took off but they drift downwards as they descend in the water-column, landing back on the launch pad. Salmon maintain their station more than some of their aerial antics would suggest.

      Whereas anglers believe that salmon are running past them, and sometimes try to hasten upriver and get ahead of them, river counters using electronic beams show that salmon ‘run’ mostly at night. Summertime salmon almost invariably use the cloak of darkness to hide their journey. Some counters work with parallel sets of beams, interrupted beams signifying a fish swimming upriver. Counters can be calibrated so that only fish of a certain size register, excluding smaller ones and trout.

      In Canada counting salmon in clear-water rivers can be unfussy: I have seen a wide placid river where the flow is channelled into a central funnel and a human counter perched on the platform end working a clicker to record every fish passing. These wilderness workers, operating in rotations, need good bug dope, a wide-awake buddy checking for bears tiptoeing down the platform, and extraordinary concentration. Happily the runs are often focused into just a few weeks, and, pressed for time, they move in the day.

      More usual aids are military-type night-sights, which, focused against a light background, make salmon watchable as they swim upstream. Most of those fish leaping under the noses of anglers are not moving upriver but performing their acrobatics for other inscrutable reasons. Nineteenth-century writer William Scrope charmingly referred to them leaping because of ‘excitement’.

      Again, anglers talk of fish running in spates. They actually wait until the debris and clouds of suspended particles have ebbed and abated and then they run, in the cleaner flow. It is dangerous for salmon to get muck in their gills, and as birds constantly preen their feathers for efficient propulsion so salmon look after the efficiency of their highly tuned bodies. One or two days after the flood-crest is a likely running time – and they are slower to chase a melting snow spate than a rain-driven spate.

      Where anglers are spot-on is in the commonplace assumption that salmon get interested in fishing flies after they have moved position. A salmon that has dwelt in one place for a month may have watched innumerable flies swinging over it and pays them no greater attention than the man on the park bench does who subconsciously watches buses looping their circuit. The same fish having shifted station will be activated and lunge at the fly, maybe attempting to purify its new location of annoying irritants.

      Tagging has shown that salmon often enter a river, stay a while, and then leave it. During a long summer salmon may climb rivers, fall back to brackish estuaries, wait for another oxygen-rich freshet to stimulate a move upstream again, and then repeat the yo-yo procedure. Although Atlantic salmon are renowned for their generally faithful return not only to the river of origin but to the section of river from where they broke out of the egg, they can mess with the rules too.

      A salmon has been tracked tasting the water on Scotland’s west coast for a while, then moving to an east-coast river, and finally ascending the third river it had trialled in one year, where it spawned. This ranks as an extreme example of genetic straying. A salmon tagged on the Dee in Wales was re-captured in Denmark. I am unsure whether a salmon tagged in Europe has ever spawned in North America; reports vary, but betting against salmon’s versatility and survivor-adherence would be a mistake.

      I was on Russia’s Kola Peninsular on a river called the Kharlovka in low-water/high-temperature conditions when it appeared to the anglers and the ghillies that the fish actually left the river, retreating to the refreshment and oxygen of the open sea. We could see them driving downriver. At this point the sea was only a mile or two distant. There would be a good enough reason: when wild salmon are closely confined fungal diseases spread fast. They can spread even faster amongst fish in low water and even disfigure a whole river population. Saltwater does the laundry.

      Salmon fungus comes in more than one type, and can keep growing on fish that are already dead. The fungus is an external manifestation of a fast-spreading microbe. It is normal even in ordinary seasons to find pre-spawning salmon with white fungus starting on their heads and backs, and when spawning is done these mouldy discolorations accelerate to be abrupted only when the fish is cleansed by saltwater. Warm, low-water river conditions make matters worse.

      Managers report that this occurred on the Tweed in Scotland late in 2011. It was not the potentially lethal condition called ulcerative dermal necrosis (UDN), in which lesions can penetrate into skeletal tissue, rather, as assessed by the river biologists, a more common fungal affliction broadly termed Saprolengia, caused by overcrowding.

      The last time fungal diseases killed huge numbers of pre-spawners in Scotland was in the 1960s, when runs were prodigious. I remember walking down to look at the water in August with my grandmother, a dedicated angler who went to the river as others go to their office. White lethargic salmon with rot peeling from them cruised aimlessly in shallow water. I recall her sombre mood. Some see fungal outbreaks on a major scale as a response to over-population, and this distressing scene did indeed coincide with a heavy run of fish. Widespread fungal attack has not recurred on this river since.

      Fishermen are the best monitors of a river-system. Their observations and speculations about this fish serve the species well. What salmon do in rivers will probably preoccupy anglers for as СКАЧАТЬ