I’VE HAD SOME PRETTY GREAT diving experiences over the years and have ticked off a lot of bucket-list items: wild dolphins, mantas, various shark species and so on, but I’ve never been in the water with anything seriously big.

And when I say big, I’m talking about animals capable of reminding us just how awe-inspiring the natural world can be, and just how small and insignificant we are as individuals. I think it’s good for the soul to be reminded of this every so often.

I’m talking about whales and really big sharks. I’ve never been in the water with a whale and, frustratingly for me and my buddy, I seem to be an excellent whale-shark deterrent. If you want to see a whale shark, just pay me to stay on the boat or dive on the other side of the reef!

As you can imagine, I’m a little bitter.

I even have a friend who has seen two whale sharks in the Red Sea, one at the entirely unremarkable dive-site of Ras Katy. The universe is clearly against me.

Conscious that I’m always talking about how great UK diving can be, I thought: “Why don’t I try to see a basking shark?” These are, after all, the second-largest fish on the planet.

I had bumped into Shane Wasik from Basking Shark Scotland at the Dive Show and he told me that during the summer spotting chances were quite good – and then told me how many they had seen the summer before.

“Cool, I’ll sign up for that,” I thought, but it was not until the following August that a family holiday to Scotland’s west coast gave me the opportunity.

We had a few nights booked in Oban, a great town with a long history of seafaring. It was nice to explore the crinkly coastline, but it was to the Isle of Mull that I would be heading.

Divers aren’t always as interested in wildlife above the surface as they are below it. Members of my dive-club might be fascinated by a lobster or two at the Farne Islands, but show them a colony of 50,000 seabirds or describe the life of the tiny puffin, which spends its winters floating around in the North Atlantic, and most remain unimpressed.

Mull could overcome that lack of curiosity in anyone. Within minutes of leaving the ferry we has seen harbour porpoises, and over the next few days I’d see a family of otters, an osprey, hen harriers and sea eagles (the result of a rare success story in wildlife conservation).

Most passengers book and board Basking Shark Scotland’s boat in Oban, but as I was staying on Mull I met the spacious and partly covered RIB at picturesque Tobermory Harbour. The team builds in a regular breakfast stop there – it has a great bakery that serves fantastic coffee.

I busied myself checking my camera, and even managed to get a few shots of plumose anemones attached to the underside of the floating pontoons before the other suitably caffeinated guests returned to the boat.

Our journey took us through the top end of the Sound of Mull then south, to the tiny specks on a map that are the Treshnish Isles, and we stayed on the look-out for baskers as we went.

I WAS PRIVILEGED THAT DAY to have sea conditions far better than any I’d experienced in the region before. As we rounded Ardmore Point we could see the low rise of Coll to the west and right up Loch Sunart to the Highlands in the other direction.

As we approached the isles I asked Hezter, one of the Basking Shark Scotland team, what we were looking for.

“The dorsal fins,” she said, reaching for her binoculars. “They’re very tall. Also, we watch for current- and tide-lines.”

Tide-lines are the areas on the sea surface where tidal currents meet and concentrate the plankton on which the sharks feed. They’re easy to see when the sea is flat and have, on occasion, an oily appearance formed from the breakdown of the tiny animals such as copepods (tiny, free-swimming and highly nutritious relatives of crabs) that the sharks filter from the water for food.

A fellow-passenger raised his voice to ask: “Is that one?”, only then to grin and add: “I never thought I’d be disappointed to see a dolphin on a dive-boat!”

The crew spotted a shark, and we headed over. It was a medium-sized animal and you could see a dorsal fin extending perhaps a foot out of the water, as well as the tip of its rear (caudal) fin.

The crew said that it wasn’t feeding because if it was you would see the snout just breaking the surface as well.

Before we had time to get into our wetsuits, the fish dropped out from view. I was reminded of the old adage about never working with children or animals as Cam the skipper throttled up and we headed west to what we hoped would be more promising hunting-grounds.

On the way we spotted more white-sided dolphins and gave them something to do as they larked about in our bow-wave. A lad on the boat with his 18-year-old reflexes took some great shots of the dolphins breaking the surface, whereas mine looked great as long as you wanted to see tails.

IN THE NEXT FEW HOURS I saw a minke whale, shearwaters and gannets, and was loving being out in this remarkable scenery. Hezter told me more about the sharks and how fish from this region wander the Atlantic and are now protected in UK waters.

Sadly they aren’t protected across their range and often get caught in fishing-nets, Their numbers haven’t started to rise noticeably – in fact worldwide the animal is still classed as vulnerable, mainly due to overfishing.

Basking sharks were hunted in UK waters for quite some time, mainly for the oils contained in their livers, which can make up a quarter of their overall body-weight. They are also taken for their fins, which can attract a very high price in the spurious “traditional medicine” industry.

Basking-shark flesh has a strong ammonia smell and is not, I’m told, good to eat. A shark’s liver acts as an immense energy store, allowing it to feed up in times of plenty. It may also help it to maintain its buoyancy.

The largest animals tend to achieve their size by eating the smallest – basking sharks have been recorded at just over 12m long and weighing 19 tons, though the largest recorded in Scottish waters is around 10m, but that’s still the size of a bus! I was itching to get into the water with some.

As we were wondering whether we’d get the chance. One was spotted, closely followed by another. We approached slowly. Basking sharks are not unduly spooked by boats, so are easy to approach.

The crew were slowly helping guests to don their wetsuits and fins – this would be a snorkel and freedive approach – and I was wondering why there was such a lack of urgency. “Once they find somewhere to feed they just slowly cruise along at the surface,” said Hezter. “As long as we don’t splash too much they’ll stick around.”

At the call to drop in we did so, and there was a brief moment as the 14°C water found my neck-seal and I shivered.

I quickly forgot the brief discomfort as what I can only describe as a bloody huge shark approached through the plankton-rich water.

Easily 5m long, the shark was in fact a small one (a female, as I learned later).

A few whitish marks on her pectoral fins and sides stood out against her leathery grey skin.

I squeezed off some shots, happy to use natural light and a high ISO setting to avoid backscatter as the shark passed by. The young guy, with his carbon freediving fins, shot under me, GoPro held in front of him, having a whale of a time while us old buggers spluttered to the surface.

I think I managed two minutes of breath-hold, but a quick review of my camera screen showed that I had bagged some good shots. The shark wasn’t feeding, and I was struck by just how similar it was to a great white in profile.

That night I showed my photos to my non-diving wife, who was regretting not coming out on the boat (even if you don’t get wet, the trip alone offers a wildlife treat). I still wanted more images, and was keen to get the classic shot of a feeding fish, mouth agape. It would be a few more days (and some great otter-spotting) later before I got my chance.

The weather was still being kind to me. It hadn’t been that great through the summer of 2015, but the water was warm and, as we approached the north-eastern shore of the starkly beautiful island of Coll, we spotted two fish, both feeding in shallow waters close to a small group of common seals that were eyeing us suspiciously.

WE KITTED UP, sat on the RIB’s sides and waited for the OK. The nearest shark was on the other side of the boat to me, so I would have to get round quickly and look towards Hezter for direction.

I finned like crazy and thought I’d lost my chance before the starkly white mouth of a shark emerged out of the gloom, bearing down on me. You see the mouth and gill-rakers before the rest of the body, and it’s quite a sight. As the animal looms towards you, you can’t help but feel a little unnerved for all the knowledge that they are harmless.

I let my camera’s aperture priority mode and fast-focusing 15mm lens do the rest. Within 20 seconds the fish had passed. It could move at only a few mph when feeding, but I couldn’t keep up.

Back on the boat, we had some homemade flapjacks and watched the sharks cruise up and down.

Luke, another shark and wildlife expert on the team, told me that the fish had been a smallish specimen at a mere 3.5m, but I was happy. I had the images I wanted and, despite the less-than-perfect visibility, was grinning from ear to ear.

I checked that my camera was attached to my wrist-strap securely. To lose it overboard now would confirm me as a shark jinx, although I realised that my GoPro had done a great job of capturing nothing!

I’d thought it was off when I hit the water, so when I believed I was turning it on as the shark approached, I was actually turning it off. Peter Scoones I am not.

It didn’t matter. I had another chance to be in the water with a second fish, a much larger one. It had white marks on its snout that Luke suggested might have been caused by nudging and bumping up against a female as a result of courtship behaviour – though little is known about where basking sharks go to meet like-minded individuals, and what they do when they get there.

I waved the boat off as it headed back to Oban, and guarded my memory-card as if my life depended on it until I could transfer the images to my PC.

OK, they didn’t feature clear tropical waters with sunlight streaming down onto the flanks of a whale shark with bikini-clad freedivers finning beside it, but I was very happy about achieving a long-held objective, and relatively easily.

Being in the water with huge animals doesn’t have to involve travelling halfway round the world.

And while we often dream of far-flung destinations and ogle the pictures printed in divEr, wishing we had oodles of cash, we often ignore the astounding encounters we can have with the impressive creatures in our own waters.

Trust me, they’re well worth it.

Basking Shark Scotland offers a number of tours from one to seven nights – single day trips start at £160. Accommodation and equipment can be pre-booked at extra cost. Departures are from Oban, and from Tobermory on Mull or Arinagour on the Isle of Coll for certain trips. Fly to Glasgow then catch a train to Oban. Overnight sleeper trains also run from London. If you drive, parking is available for multi-day itineraries. Diving/swimming is dependent on weather conditions and sea state.  Bring warm, waterproof clothing and a packed lunch. www.baskingsharkscotland.co.uk