AT ONE TIME, SIMPLY SPOTTING and viewing basking sharks, let alone getting in the water and swimming with them, was down to luck. They might be a bonus sighting on general wildlife sightseeing tours off the coast.
Basking Shark Scotland is an operation that has started up out of Oban, and its focus is on finding and swimming with the creatures.
With British and European divers flying halfway round the world for “big fish” encounters, it seems that the humble basking shark has been somewhat forgotten.
Its allure doesnt seem to match its status as the world’s second-largest fish, only the whale shark being bigger.
The operation has been made possible by the shark hotspot around the islands of Coll and Tiree, due west of the Sound of Mull, with which many British divers will be familiar.
The sea around the islands becomes relatively shallow compared to the deep Atlantic surrounding them and the theory is that the shallows funnel the plankton into a concentration that makes it a tempting feeding ground for these sharks.
Gunna Sound, the channel between Coll and Tiree, is known in particular as an epicentre of basking-shark activity.
In Oban I boarded the boat, a large RIB with twin diesel inboard engines and largely enclosed from the elements. We headed up the Sound of Mull for the two-hour haul out to Coll.
Knowing that basking sharks are there is only half the battle, because the fickle Scottish weather also plays a part in the success of a days shark-spotting.
Despite their huge dorsal fins, spotting baskers in choppy seas can be tricky, especially as the grey skin of the shark offers good camouflage against the deep blue of the Atlantic water.
I had booked five days of shark-spotting scheduled to coincide with the “Coll of the Sharks” festival in Arinagour, Colls main town.
The festival would feature a few speakers, including researchers revealing some of their findings and BBC underwater cameraman Doug Anderson, who had recently filmed the sharks for the BBC Hebrides series.
We would be based in Arinagour, within easy reach of the sharks. A 20-minute ride would take us to Gunna Sound or other known hotspots, depending on the wind condition.
On the first day we tried our luck at the Cairns of Coll, a few islets at the north end of the island where a massive seal colony resides.
The white sandy beaches and turquoise waters brought on by momentarily clear blue skies made it hard to believe that I was in Scotland. The chill of the water soon reminded me of where we were as we got in, however, and we were quickly surrounded by playful seals, the pups being particularly boisterous.

WE HAD TO WAIT until the end of the first day for the first ominous shape of a basking shark fin to come into view. Reminded of the swimming etiquette – dont get too close and dont use camera flash, among other things – it was time to get into the water.
We donned our 7mm wetsuits and managed to get a brief encounter with the beast as we dropped in. Its gaping white mouth contrasted against the dark blue as the massive shark came into view.
It seemed large, but skipper Cameron explained that this one was actually quite small, and that such specimens tended to be more skittish than the bigger ones, which were more inclined to ignore the passing swimmers.
A rising south-easterly wind on the second day prompted a run over to the more sheltered waters on the north side of Mull, where sharks had been spotted in previous days.
On the way over we came across an aggregation of five sharks. They were out in exposed waters, and as it was early in the day we decided to try to find some in a more sheltered area first. This was a mistake, because we didn’t see any sharks for the rest of the day!
The weather cleared, and on the third and fourth days the sun shone and the wind eased almost completely, providing ideal conditions. Everyone on board was soon getting incredible encounters with the sharks, which were more than obliging in their swim-bys.
Often the most fruitful encounters occurred when a shark was working its way along a tide-line – a clear line at the surface where currents mix and stir up the plankton.
There the shark would often swim past and then double back numerous times, right in front of the snorkellers.

THE SHARKS OFTEN SEEMED more docile in the afternoons, and it was then that we had our best encounters.
Cameron spotted a fin on the way south to Gunna, but approaching closer we saw that there were no fewer than 15 sharks in the tiny bay.
Jumping in, it was easy to see why – the water was a thin soup of plankton and jellyfish. The combination of the right current and wind direction must have forced this dense concentration of shark food into the bay, and these baskers were gorging themselves.
Time after time the sharks swam past, paying no attention to the snorkellers watching them so avidly, simply engrossed in the feast.
At one stage I had two sharks in my line of sight – remarkable, given the low visibility. I have enjoyed numerous big-fish encounters, including great whites, humpbacks and whale sharks, but seeing these leviathans was every bit as spectacular and thrilling.
The trip was not just about snorkelling, however, and that evening we went for a dive off Coll Pier, right next to Arinagour. The pier is still operational and dives need to be planned accordingly, but its pilings provide a haven for all kinds of critters.
Macro photo opps were numerous, though the late-evening sunlight would have made for good wide-angle shots.
The pilings are packed with life – plumose and jewel anemones, scorpionfish, decorator crabs and countless nudibranchs made this one of the finest UK dive-sites I’ve seen, and would be worth the trip alone.
Coll offers many other diving opportunities, including the Tapti – one of the best wreck dives off the west coast.
The success of the trip probably hinged on dedicating plenty of time to it. Bearing in mind the temperamental weather, I would recommend dedicating as many days as possible to maximise your chances of getting in the water with these icons of British wildlife.
This is not the kind of trip where the action always comes thick and fast, but there is much wildlife to see, from rafts of puffins on the water to diving gannets and a seal colony on the Cairns.

Having had such good action on days three and four, we opted to take day five off and explore Coll.
We took bicycles hired from the Post Office in town around the picturesque little island, travelling to the west side where wild Atlantic swells were crashing into the numerous white sandy beaches. Once visited, Coll is hard to forget.

GETTING THERE Day trips with Basking Shark Scotland leave from Oban. Nearest airport is in Glasgow. The boat-ride from Oban to Coll takes about two hours.
DIVING & ACCOMMODATION For anything longer than a day trip you can stay overnight in the new Coll Bunkhouse, or pay a little more for B&B at the Coll Hotel.
PRICES £150 per swimmer for a one-day trip, £299 for two days at the Coll Bunkhouse and £450 for three days.