| Shark Encounter |
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Jean Lawman reflects on the arrival of BaskingSharks in Cornish waters this summer The sea rippled away to the horizon, pallid blue and milky – the usual prelude to a hot summer’s day in Cornwall. It was heaving gently as if it was breathing. The surface was opaque, like a thin layer of silk, but where it nuzzled the rocks it glittered and sparkled in the backwash. It looked inviting and, after the initial shock of immersion, felt refreshingly cool; my skin was tingling. The cove was deserted, the sand unblemished, save for the tiny footprints of Mink that breed among the rocks – perfect for an early morning swim. Nearby, a Razorbill, thick-billed and sharply black and white, bobbed on the surface with a newly fledged chick about two thirds as big, thinner billed and dusky plumaged. Some dark disturbed patches on the water indicated that there were shoals of small fish here. With a flick of its folded wings the adult bird shot below the water to chase and catch small fish for its hungry offspring. The deserted one floated aloft, feet paddling and kicking as it patiently waited for its next meal. It was vulnerable, but there were no gulls and no seals around, at least for now. It cost the Razorbill less energy to take the chick to sea, and so to the food source itself, than continuing to visit the breeding ledge to feed the youngster with regurgitated fish. You could hear the chick calling– a faint piping whistle blown away on the wind - enabling contact other than by sight, should the two be separated. Our Razorbills would soon be gone away from our coast, for the moult and a winter at sea. It was a magical atmosphere, as serene and beautiful as a Cornish cove can be; the comfortable warmth and subtle light of the sun yet to rise high, the gently undulating sea and the sonorous moan of the buoy warning ships of a dangerous reef. There was a dreamy quality to the day, even when the black fins glided through the water in front of me, only twenty feet away; there remained a calm and stillness. First came the huge triangular dorsal and then, some t10 or 12 feet behind, the thinner tail fin, the latter distinctively notched and recognizable as a shark I had seen here before. Add another 12 feet or so to the tip of the upper jaw and it was roughly 25 feet long. It was a passive encounter, not planned or even thought of. We were each going about our own business on this day in early July; myself enjoying the moment in a typically human, self indulgent way, and the shark cruising, or rather feeding, although I couldn’t see the gaping mouth. It may have been totally unaware of me, but I felt its presence, its hugeness and its darkness in the water not far away. I felt safe; there is nothing to fear from a plankton eater at this distance. I didn’t try to get closer; that could be a foolhardy thing if it decided to throw its weight about in a manoeuvre. Disturbing it would have spoilt what had been a totally natural and chance encounter. It passed by, its wet fins wavering with the slow, sideways motion of the body and glinting as they caught the sun. Slowly it drifted on and I watched it going further and further away, until it was lost in the dip of a swell. The Razorbills had moved away too and were heading westwards around the rocky shore in their pursuit of fish. Both shark and birds were gone. Cracked sunlight played on the sand in the shallows where I stood and the only life form was an incoming butterfly hurrying over the water, heading for dry land. It was a visitor from the south. A Red Admiral had crossed the channel to exploit our long summer days for the chance of reproduction. Up the beach and over the cliff, and it was gone. There was no sign of the shark when I scanned the sea as I left the cove, but further out two smaller fins momentarily broke the surface close together, one much smaller than the other. Then the small one surfaced alone. Half a minute passed and the two appeared again, and then again. It was a porpoise with a baby. Here, off this tiny Cornish Cove, one of the world’s smallest cetaceans was keeping company with the world’s second largest fish, only the Whale Shark is larger. Evolution had set different paths for these two creatures; the shark destined to remain in the sea and retain a primitive form, whilst the cetacean evolved from an animal that had left for the land and returned millions of years later far more sophisticated. Both were superbly adapted to this ocean where life began. The Basking Sharks will have left as this article goes to print, at least we assume they will have for they live underwater too, but what a summer it was! There were high counts from some headlands in Cornwall. What magic it is to scan an area of calm sea, often quite empty of life, and see that is alive with numbers of black fins spread around the whole area. The sharks particularly exploit offshore currents and tide races that tend to concentrate the plankton blooms, and they can often be seen moving up and down these tidal drifts. Dolphins and seals are usually, but not always, seen off our coast in small groups or singly; a large number makes a big impression. So it is with sharks, especially when they are spread over a wide area. A few days after my close encounter in the cove south of Land’s End, there were 53 feeding on the surface off Pendeen Watch, in a wide arc stretching westwards to Botallack Head and eastwards to Gurnards head. The water that day looked thick and oily as it does sometimes in mid summer, probably due to the richness of the plankton. Some were close inshore, others several miles out. Some were in clusters of between five and 10, others on their own. It was a blue arena of sea and sky where black fins cut sharply into our world of air and light from their hidden world below. Many were between five and eight metres long, but a few were under three metres. It was an unforgettable sight. Now and again there was a big white splash, and I mean big - far bigger than that resulting from a gannet dive or a dolphin jump. Some people don’t believe that sharks breach, jump out of the water, and I didn’t for a while; it seemed like a fishermen’s tale until one day through my telescope I saw a massive body, clearly that of a shark, lurch out of the water and throw itself over backwards. Sometimes they breach twice or even three times in succession, and the best way to see it is to look carefully at the same spot through binoculars and hope that you may catch it again. The large size, the impression of black and white, the big fins, and the power of the leap are spectacular, and it’s not hard to see why sometimes some people believe they are seeing Killer Whales or Orcas. Why do they breach? Nobody knows – but suggestions are that they are ridding themselves of parasites or possibly communicating in a primitive way. They are fish and cannot have the sophisticated social life of a dolphin or whale. Just when the sharks seemed to have moved away altogether, numbers built up again towards the end of July. There were 68 sharks - and one big splash! - in the same area off Pendeen during another spell of settled and very hot weather; a day of butterfly immigration with Clouded Yellows and Red Admirals flying speedily and non-stop over the heather. Careful scrutiny of the sharks revealed only one very small individual - under two metres, close to the suggested size at birth of 1.7 metres. Experts believe that the apparent lack of small sharks may be cause for concern as it may indicate a low reproductive rate within the population. Although Basking Sharks are well distributed worldwide, they are most regularly recorded around the coast of Britain. We, in Cornwall, are privileged indeed, for there are three hotspots for sightings: the Isle of Man, around the Isle of Arran in Scotland and the South-West of England. This is mainly to do with the surface flush of zooplankton off our coast in the spring, something often noticed by divers and fishermen prior to the sharks’ arrival. Our irregular and uneven seabed, combined with strong tides, causes a great amount of mixing and upwelling of the water, resulting in the plankton appearing at or near the surface. Accordingly, there are some places around our coast where the sharks particularly like to gather and feed, like the southeast section of the Lizard coast, around Land’s End and the seas off Padstow and Boscastle. Soon after the encounter in the cove, the sharks moved from the south coast round to the north, hence the two high counts from Pendeen, although at the beginning of August several turned up again off the south coast of Cornwall. Their movements reflect the whereabouts of the plankton masses that occur in patches and shift around with winds and currents. Wherever these patches are, the sharks will stay with them. Studies over several years have shown that as the summer goes on they gradually move north up the west coast of Britain, following the food, and eventually arrive in Scottish waters in late August/September. It’s not every year that we see large shoals, although each year turns up some reports. Numbers appear to be cyclical with peaks about every seven to 10 years and two peaks in the year itself, May and July. Recently, 1989 and1998/9 were especially good years. There were two reliable reports from Kennack Bay, on the Lizard, of 500 sharks in 1998. Imagine that! The mind boggles at the amount of plankton just one of these sharks needs to stay alive. It seems incredible that these giants, like some of the large baleen whales, although they will also take fish, can thrive on tiny, often microscopic, organisms – tons and tons of them. Plankton is not always on the surface and neither are the sharks. In winter it is assumed that they migrate to deep water, a fact substantiated by the amount of squaline in the liver oil in spring; this is a chemical compound found in deep water species. They are certainly only rarely seen in the winter months. Satellite tagging has shown that they travel considerable distances, over 3000km, and dive to depths of over 750mts. It is not known as yet whether regional populations exist in the Atlantic or if there is one highly migratory stock. As winter draws to an end, the warming up process begins and new life begins to flourish in the sea. This is when individuals start to move into shallow water near to our coast. Most of us see sharks only when they are on the surface - feeding not basking as it was once thought - but they can be seen underwater from a cliff top, if the sea is very clear. The best counts are made on calm days, and especially when they coincide with weekends and Bank Holidays. This is to be expected, but it may also be true that this weather is conducive not only to their being easily seen by lots of people, but also to the aggregation of plankton and hence concentrated feeding activity. One of the best places to view them is from the open air Minack Theatre. It feels like a foreign land as you sit on the terraces, surrounded by the flamboyant colours of a variety of exotic plants, with the sharks in the bay below. If you are lucky, in May/June, there may be some spirited entertainment of a different kind than that promised on the programme, if the local pod of Bottlenose Dolphins ventures into the bay. The Minack is good for viewing wildlife in general. Offshore, Terns enter the bay and plunge dive for small fish as they pass on migration, Shags dive deeply, snaking along underwater in pursuit of their particular prey, Mullet group and loaf on the surface just off the rocks and you may glimpse the tall fin of a Sunfish flopping sideways onto the water. The water tends to be calm and clear here, and it is sometimes possible to look down on the sharks when they come in close and see them underwater, dark shadows in the turquoise void. They appear to be black but are actually a mottled grey if seen close up. Massive jaws gape widely, extending the long gill slits and turning the head region into an inflated sack through which tons of water will pass and be sifted for plankton. Sometimes the white or pink interior is visible. If the head can be seen, the total length of the animal becomes apparent. Divers have the most spectacular views when they encounter them underwater. The arrival of the sharks is an event eagerly anticipated by local people and especially the staff at the Minack who, being able to look over the bay during their working day, often see the first of the main influx. Yet naturalists in Cornwall begin to look out for the sharks in March; this is not too soon for an early record. Further sightings are made through the summer with the occasional one as late as October. There are few accounts historically of large shoals of Basking Sharks. The author Gavin Maxwell hunted and shot the sharks of the west coast of Scotland as a business venture in the 1940s and was impressed by the size of the shoals he saw from his boat: “They were packed as tight as sardines, huge grey shapes like a herd of submerged elephants, the furthest down dim and indistinct in the sea’s dusk”. The man best known for his book about otters, ‘Ring of Bright Water’, seemed to harbour no guilt about destroying them and clearly had a complex personality. The downside of seeing the sharks today is the awareness that they are still threatened, even though the high grade liver oil for which they were once targeted is of no value because of more economical and easy to obtain substitutes that can now be used in all kinds of products, from cosmetics to use in the aviation industry. There are few places today that use the meat for human consumption, but there is now a flourishing trade for their fins for use in making shark fin soup, a delicacy in Asia and in Asian restaurants all over the world. It is an extremely lucrative business for both targeted fisheries and where sharks are part of an accidental by-catch. This represents the biggest threat to the Basking Sharks today. We, in Cornwall, see large numbers of sharks and it is easy to assume that they are doing well, but it is not so. The global population is assessed as vulnerable on the IUCN Red List of Threatened Species and is protected internationally under Appendix 11 of CITES - the Convention for the International Trade in Endangered Species. The Basking Shark is also protected in British territorial waters under the Wildlife and Countryside act. This means it cannot be killed, captured or disturbed out to 12 nautical miles. The rules are grey as far as disturbance is concerned, but there is a Code of Conduct drawn up by the Shark Trust for boat owners, divers and swimmers. Nevertheless, these magnificent animals, that give us so much pleasure and excitement, seem to have to contend with far too many boats and swimmers these days while they are trying to feed, especially in some of our more populated and accessible bays. Since we understand so very little about them, the argument is one of what constitutes harassment and what doesn’t. They are magnificent animals and we want them to keep returning to our waters, so perhaps it’s best to give them plenty of space anyway. |