Magical creatures

AN APPRECIATION OF THE BASKING SHARK

Every summer brings the long-awaited return of old friends: the trilling song of a skylark floating down on the breeze, the golden sweetness of sun-warmed gorse, and the arrival I look forward to the most; the sighting of the first basking shark. Basking sharks travel enormous distances, crossing entire ocean basins in their search for plankton, and are frequently sighted around the west of the UK between April and October, congregating in large numbers in the rich waters off the Hebrides. As soon as the news breaks that the first dorsal fin of the season has been sighted, usually in the far west of Cornwall, my lookout begins.

Like most sharks, the basking shark is thought to be a slow breeder and its numbers depend on regular plankton blooms, which are changing as the oceans warm. Fishing of basking sharks for their liver oil, prized as a smokeless lighting fuel, only ended in the UK in 1995. Although no longer targeted, they remain an endangered species and are often injured by boat strikes and nets.

Some years I won’t see a single one, but the joy is in watching hopefully for days, weeks, the whole summer, as the sea cycles between indigo, grey and turquoise, knowing that somewhere out there the gentlest of sea monsters is tracing its silent path. The joy is in what might be.

Basking sharks ought to be hard to miss. Measuring up to ten metres long, these fish are second only to the whale shark in size. Despite this, they can be elusive, and dive to at least 1,200 metres. What we know about them raises further questions. Why do newborn basking sharks have snout-like snub-noses? How do they navigate? Why does this colossal fish leap explosively out of the water?

My first basking shark sighting came not long after

I had first seen Jaws on TV as a child. On a still August day, I was walking along the cliff path in Mawgan Porth, Cornwall, and in the bay below, dark turtle shapes of surfers floated on the becalmed ocean in huddled groups, wetsuit-clad legs trailing in the water. Sunlight dappled the emerald shallows, glinting off the surface.

I saw the shape before the fin, a shadowy presence like a rocky reef, the moving sea obscuring its edges. As I watched, ripples broke the surface, the tips of the great dorsal fin and tail. The scene reminded me of old maps I’d seen of oddly-shaped coastlines surrounded by mythical monsters with fearsome teeth, spines, and tentacles.

This was no giant squid or great white shark, however, but a quiet giant, the ‘roomsized monster with a matchbox brain’ of Norman MacCaig’s poem, Basking Shark. It channeled seawater into its vast, pale gape, filtering out zooplankton and expelling water through fluttering gills.

Surfers unaware of the magical beast beyond, and seen only by me, the basking shark traced a wide arc across the bay before sinking out of sight, melding back into its ocean world. Long after it left, I was still watching.