THERE ARE TWO FISH IN THE WORLD WITH SLAP-YOU-IN-THE-FACE IMPACT. One you usually have to pay thousands of pounds to see - the whale shark. The other lives off the coasts of Britain.
 I had always wanted to see a basking shark. I had started out some 10 years ago but with no clue how to go about finding one. My quest had begun as an idea, quickly became an obsession and ended up nearly driving me mad.
 The first year was all just pipe dream. I had no idea who to ask, where to go or who to go with. I phoned boat skippers, who all said much the same thing: We see them from time to time, but you never know when or where. Not a lot of hope there.
 The second year, after some Sherlock Holmesing, I knew I had to focus my attention on Cornwall, but again had no one specific from whom to seek advice.
 I researched the animal, but found so little information that I wondered if anybody else actually realised that basking sharks existed!
 Were talking about the second largest fish on the planet, after all, growing to the same length and weight as a single-decker bus. Basking sharks feed exclusively on plankton and are the coolwater equivalent of the tropical whale shark. And until a handful of years ago, so little research had been carried out that scientists had no idea
 where these sharks went to in the winter, how they bred, where they lived and how big the population was.
 We now know from satellite-tagging programmes that basking sharks live in UK waters and follow the plankton to deeper water during the winter. The best time to see them in Britain is between May and June and there is a two-week window in which sightings are common, during the first plankton bloom.
 But when my interest first took hold, men knew more about what women wanted than about basking sharks. Anyone who saw them at sea during the summer was as much an expert as the experts. Yet there had been a fishery off the west coast of Scotland in the Firth of Clyde, near the Hebrides and off Shetland, as well as another one off western Ireland, around Achill.
 Bearing in mind that we knew as much about the creature as a six-year-old understands quantum physics, these fisheries were believed to have taken between half and 80% of the basking shark populations in those areas in a decade.
 Worst of all, with modern research and tracking programmes, marine biologists have shown that the recovery rate of a population is a mere 1% per year.

What mankind is like
In the 1980s, when the fisheries crashed, UK fishermen stopped hunting basking sharks because it was no longer profitable.
 Yet it took the British government until 1998 to grant full protection in British territorial waters.
 Sadly, this shark, with its global distribution, is still hunted in other parts of the world to feed one of the most abhorrent industries mankind has created.
 Before 1900, basking sharks were targeted because of their liver oil. The liver is massive and yields large quantities of high-grade oil that was used in lighting, tempering hot steel, cosmetics and also in medicines.
 Synthetic substitutes replaced shark oil in the early 20th century, and by 1970 the use of basking shark oil was dwindling - much like the populations.
 Then the Chinese started promoting the benefits of sharkfin soup. In 1990 shark oil was worth around £250 per ton, a steep drop from the £550 per ton it was worth in 1970. Yet the price for basking shark fins in the Ô90s jumped to around £100 per kilogram. A basking shark can yield 90kg of fins, so you can see why they are so sought after.
 Learning this, I started to doubt whether I would ever see a shark at all, but I didnt give up.
 In my third year I was ill when the sharks arrived during the summers first plankton bloom, so I missed the event again. They come to the surface only when the plankton is present, and the first bloom is the best time, as clouds of the tiny planktonic creatures form in the warming water.
 So dense are these clouds at the beginning that the sharks gather in small areas, making them easier to find. When the plankton disperses, so do the sharks. Seeing one becomes a game of chance.
 In the fourth and fifth years, I had to work. The weather dictates when the plankton bloom occurs, and it doesnt follow a pattern. Getting it right means being able to drop everything and get to where the sharks are. Bosses with whips and deadlines are not the friend of the basking shark-hunter. I was left behind a desk, frustrated to hell.
 In the sixth year, I had my chance.I was going to the Isle of Man. This small island off the north-west of England is something of a basking shark magnet, and I was full of hope. It wasnt a cheap trip. Flight, boat and accommodation all added up and, sadly, all for very little.
 I did see my first basking shark, but it was a small one and in no mood to be approached. So I had to make do with a fleeting glimpse. I went home empty in pocket, empty in camera and empty in heart. It was a valuable lesson, however. Just because something is out there doesnt mean that you will see it!
 The next year I was on holiday and missed one of the largest gatherings of sharks ever recorded off the South Coast. Some figures put the total at 500 of the buggers. Whatever the true figure, that many sharks had not been seen in the UK for many years and, coincidentally, it was also the first year that the sharks had been granted full protection in UK territorial waters.
 Everything had come right at the same time. The weather was calm when the plankton bloomed and this created tightly packed clouds close to the shore, which attracted the sharks.
 On another holiday the following year I began to think I would never have the chance to get into the water with a fish so large I could live in it. And the year after that, there wasnt a sign of them. May turned to June, and no one had seen a thing.
 The weather had been terrible at the start of May and experts thought the bloom occurred then, but few people could get out on the water and the plankton was pretty dispersed when it formed. The sharks were there, but out of sight.
 Last year, I was on the basking shark text alert run by Porthkerris Divers in Cornwall. When the call came through, I arranged to get to Cornwall as soon as I could. But the weather stuck its boot in my gut, as rain and strong winds kept boats on the shore for several days and had me tapping my feet in frustration.
 I made the seven-hour journey to Cornwall from London as soon as the weather cleared. I boarded Porthkerriss Celtic Cat, a boat built with basking shark-watching in mind.
 Its height above water level gives Mike, the captain, a perfect vantage point from which to scan the water for dorsal fins breaking the surface. Hes an expert at it, and I joined in the watch.
 As an experienced wildlife photographer, I know that the secret formula is 80% patience, 15% luck and 5% skill. But the sharks were testing every bit of that 80%. We would be in the right place at the right time - it was just that the sharks didnt show. The first day we saw nothing but a harbour porpoise feeding in the current washing around Black Head, close to the end of the Lizard Peninsula.
 The area from Black Head to Lizard Point is called Cadgwith Bay, and when the tide comes in, great clouds of plankton get trapped here. It makes the area prime basking shark-watching territory.
 But the plankton had dropped and the sharks had followed. The bay could have been full of sharks, but if it was, we couldnt see them.

Tough choices
 The next day was the same. So was the next. Three days of trolling around and seeing not a lot was, to flirt with understatement, disappointing.
 It looked as if the plankton had beaten me again. Instead of staying for another day of disappointment, I went back to London. So fed up was I that I drove back that night, arriving home around 1am.
 The next day, I emerged from a tube station and my phone sounded. I had, according to the electronic voice, a new message. It was Mike from Porthkerris.
 I was fighting my way through crowds of people eager to get home, and Mike was standing on the cliffs overlooking Porthkerris Beach, watching six basking sharks cruise up and down.
 Now I was in a quandary. It was Saturday evening and I had to work on Monday morning. That left me Sunday to get to Cornwall, find the sharks and get back - a total of 12 to 14 hours in the car. I made a snap decision and at 4am the next morning pulled away from my home and headed for Cornwall. It was the start of a very long day.
 By midday I was on the bridge of the Celtic Cat, scanning the calm Cornish water for large black fins. Tired, yet full of hope, I eagerly searched the waters.
 Three sharks had been spotted from one of Porthkerriss dive RIBs in Coverack Bay that morning. We headed for that location but found nothing, so continued around Black Head and into Cadgwith Bay, where the advancing tide was bringing in fresh clouds of plankton.
 There should have been plenty of sharks here. The conditions were flat and the plankton was up, but sadly the baskers where not. My enthusiasm started to wane as my heart began to sink inside my chest. Still I searched the water, but with a rising level of frustration.
 Every wave started to look like the top of a basking sharks dorsal fin. Soon I was seeing phantom shark fins all over the place, which added another cloud layer above my sinking mood.
 The clock was ticking and I was running on borrowed time. I could not believe that another year would go by leaving me empty-handed. I knew the sharks were there somewhere, but that certainly didnt help matters.
 Slowly Mike cruised past the small fishing village of Cadgwith and on towards Lizard Point. Still there was nothing but false alarms. Lobster-pot fishermen really should be banned from using black marker buoys at this time of year - it gets very distracting.
 We motored out around the southern point of the Lizard Peninsula to see if the sharks were working any plankton clouds further out to sea, but again frustrations grip had me by the throat, and wasnt about to let go.
 At half past three, Mike decided to head home the way we had come. I was devastated. It felt like failure, another year to add to my growing pile.
 I thought about giving up on basking sharks. They were a waste of time.

Luck turns my way
 We skirted back into the eastern side of the Lizard Peninsula and into Polpeor Cove. Several pot buoys were visible and the weather was even calmer than the morning. The water was turning somewhat glassy and the sun was glinting off the waxy-looking sea, but the idyllic scene was not enough to lift my heavy mood.
 And then I saw it. Close to the side of the boat, we passed a basking shark. I shouted to Mike, who immediately swung around and brought the cat to a stop. The shark was close inshore, cruising slowly with the tip of its dorsal fin just out of the water. I had found one.
 I hurried into my drysuit and rushed to the dive platform with camera, mask, snorkel and fins (scuba gear is too cumbersome and creates too much drag to be of any use when swimming fast at the surface). Mike expertly positioned the Celtic Cat to put me in the sharks path, and I slipped into the water.
 The hot day was not reflected in the water temperature. It was cool enough to take my breath away for a second and it took a few moments to regain my composure and concentrate. I searched the water, but the visibility was only around 6m and the shark was well out of sight.
 I looked to the boat, and everyone was still pointing in front of me. I kicked hard to push myself out of the water as far as possible and saw the dorsal fin still heading my way. I swam slowly towards it and then, out of the gloom, the water turned darker. A huge mouth appeared.
I stopped, and willed the shark to come closer. When it was in range, I started to shoot, but it veered off at the last moment, preventing me from getting a head-on picture. As it glided past, I started to swim alongside the 6m-long animal.
 It swayed its huge tail so gently that it looked as if it was making no effort at all. I, on the other hand, had to swim so hard that I thought my legs would overtake my head. These critters can move, and under water I felt like a six-year-old trying to keep up with an Olympic sprinter.
 I quickly finished a film and headed back to the boat to change the roll. I got back into the water in front of another shark, which was working the same area and had appeared while I was in the first time round.
 Again, as it appeared from the edge of the visibility, I froze, hoping to be no more significant than any piece of flotsam in the water. The ploy worked. The basker breezed past so close that I could have touched it.
 Instead, I held the camera out as far as I could, and fired off shot after shot.
 As it drew level with me, I started to swim next to it. Less than a minute later my leg muscles burned, my chest fought for breath and I was getting absolutely knackered.
 It didnt take too long for the shark to start to pull away, and it carried on, leaving me feeling like a 70-year-old with heavy shopping bags chasing an ever-receding bus up the high street. My heart threatened to burst from my chest as I hauled myself out of the water. I sat on the dive deck for a few moments to catch my breath.
 It was all done in just over 10 minutes of in-water time. Ten years wait for a 10-minute experience may not seem worth it, but it was. I just hope I dont have to wait 10 years to see my next one.

  • The Marine Conservation Society has produced a Basking Shark Watch Report that details findings from 13 years of research (01989 566017, Porthkerris Divers offers trips for snorkellers, 01326 280620,

    Gavin Parsons stayed at the Three Tuns Pub in St Keverne near the Porthkerris Dive Centre (01326 280949,

  • Divernet