TOBAGO
"A murky surface layer and strong currents" was the forewarning I had received about the Atlantic side of Tobago. "Once below the surface layer, visibility improves."
     Today, at Bookends, there is no murky surface layer, only stunning visibility and a gentle current. As a photographer, I won't turn my nose up at clear water and bright sunlight.
     Bookends is a dive that begins on rocks that just break the surface to the south of Little Tobago, and is named after the peaks that surround a large bowl in the rock. The standard plan is to drop in almost on top of the bowl, swirl round a couple of times, then pop out and drift north with the current.
     One of the divers has some problems descending. Not much, but the short delay and a surface current mean that we miss the tarpon. Down on the gently sloping reef, the current is much milder and we drift. We could go against the current, but this is Tobago and, as with most Caribbean life, you go with the flow.
     This was my first dive at Bookends and it didn't even occur to me that we had missed the tarpon bowl until after the dive. I was having too good a time on the reef. All the usual hard corals are there in profusion, but the real pluses are the sponges. Parades of strangely two-dimensional grey barrels indicate the usual strength of the current, while bright red, orange, green, blue and violet tube and finger sponges add colour to the scene.
     I zoom round the other divers seeking good camera angles, lining up divers with outcrops of coral and sponges, then flitting on to catch shoals of grunts and jacks and all the usual reef fish.
     I am glad I had a last-minute change of mind before the dive, swapping a fish-spotting lens for a wide-angle to catch the overall scene. Fish-spotting would have been good, but the big scene is magnificent.

My hosts for this trip are the Hilton Hotel and its attached dive centre World of Watersports, at the south end of Tobago. Little Tobago would be a long way to travel by boat, so Rae De Beer from WoW drives us by car to Speyside, where he has an arrangement with Rene, a local boatman.
     The road winds along the coast, never quite unmade and never quite single track. Typically Caribbean small towns and villages on the way have familiar names. The capital is Scarborough, then we pass Hillsborough, Goodwood, Pembroke, Richmond and Roxborough, where Rae tells me the island's recompression chamber is located. The journey takes just over an hour.
     A few days later I am back at Speyside and again diving Bookends, this time with Rikky Knowles, Rae's business partner at WoW.
     There is still some surface current where waves wash over the protruding rocks, but under water it is almost slack. I head straight for the tarpon bowl.

I admire the general scene and reef fish that live along the edge of the bowl, but it is not until I look upwards into the shallows that I spot the tarpon.
     Even then, I don't spot them immediately. I am watching the dense clouds of tiny white bubbles surging above me as waves from the Atlantic crash over the rocks. A contrasting dark cloud of tiny silversides pulses in and out, maintaining an almost solid but living margin against the white foam.
     Then a clear ring forms in the shoal, transforming into a rounded cut between the silversides and the foam.
     A procession of four or five tarpon cruise through. They are huge, silvery fish with lantern jaws, almost prehistoric in design.
     I move shallower until I am skirting the billowing clouds, waiting for the right fraction of a second to catch the moment. It is the sort of scene best caught on video.
     The reef below me is without doubt an excellent dive, but the clouds of tiny white bubbles, silversides and tarpon is something else. Striving to balance this complicated scenario, it takes me another 20 minutes to finish the film. I fire my last shot on a shoal of jacks that streams through, adding yet another moving element to the equation, and wish for more than 36 shots on a roll.

Another significant dive at the Speyside end of the island is Kelliston Drain, often referred to simply as Brain Coral, after a huge specimen which is thought to be the largest in the Caribbean.
     The dive starts a fair way upcurrent from this attraction, the standard plan being to drift along a frustratingly nice sloping reef before meeting the brain coral towards the end of the dive. As at Bookends, the current is unusually light, so we end up swimming to make progress.
     I say "frustratingly nice" because I am faced with the dilemma of shooting film now on the reef, or saving it for the brain coral. As with most dives on Tobago, there is a strong showing of angelfish, presumably prevalent in these waters because they like to eat sponges.
     I might have confessed previously that brain corals are a favourite of mine. I like the clean domed outline and the intricate maze of grooves between the polyps.
     My reward is certainly the largest example I have ever seen, with the added bonus of a French angelfish that has stopped by to be cleaned by the numerous gobies and small wrasse that live on this well-marked cleaning station.
     Less spectacular but still enjoyable dive sites can be found on the more sheltered Caribbean side of Tobago, departing from the pier at Pigeon Point at the south-west end of the island.
     Divers meet at the spotless modern dive centre, the sort of building you would expect to be attached to a top hotel, and then travel to the pier by minibus or pickup. On the way, we collect divers staying at other locations and fresh fruit for snacking between dives. The journey takes about 15 minutes.

Continuing the theme of familiar names, I dive a reef at Arnos Vale, a name shared with a street close to my home in Bristol.
     The inshore reef here is a popular snorkelling site. Further out, it breaks up into a sandy seabed with shallow patches of reef, ideal for fish photography because the patches concentrate and localise the fish.

Further up the west coast, an early-morning start is needed to reach the Sisters, a group of rocks a good 45 minutes away. On the way, we pass the small town of Plymouth and bays that reflect a buccaneering history, with such names as Culloden and Mount Irvine. Further north are the more explicitly named Bloody Bay and Man o' War Bay.
     I am a little disappointed with the dive. For something which we have made such efforts to see, it is all a bit average.
     An average reef in the Caribbean is still a good dive, but I am expecting not good but fantastic.
     Perhaps it is the unusual lack of current again. We drop in to the north of the rocks, intending to drift the whole length of the reef, but have progressed only halfway along it by the time we surface, and the second half of the dive is the best, featuring large rocky pinnacles with steep walls and canyons in-between.
     I guess the corollary would have been far more difficult for our boatman. Had we dropped in halfway along the reef in a ripping current, we would have been swept off and dispersed into blue water in the first few minutes.
     Also on the west coast, the must-see wreck is the Maverick, once a car ferry running between Tobago and Trinidad. Pensioned off when replaced by a larger ship, it was cleaned up and sunk as an artificial reef in 1997.

Descending the line, the visibility isn't perfect, but good enough. I am only a few metres down before I can pick out the rough outline of the superstructure from the general haze. At the end of the line, the stern A-frame mast stands out better against a light blue background.
     Skipping the lure of the car deck for now, I continue down past the square stern to the seabed. The propellers are removed, but the two shafts and rudders are beautifully adorned with soft corals in a slight scour beneath the hull, an indication that currents can be stronger than the slack water in which I am diving.
     To be pedantic, the Caribbean does not possess true soft corals but "octocorals", which form fans, whips and other shapes in-between. However, "soft corals" is the term commonly used, so I will stick with it.
     Rather than follow the outside of the hull, I head up to the car deck at just over 20m, swimming happily forward inside the wreck with a brief diversion to the engine room and its pair of diesel engines. Access is easy, with large holes cut through the deck plates.
     Towards the bow, a shoal of grunts takes up formation in penetrating shafts of light.
     Choices for exit are between a large square hatch in the bow deck, or up a stairway and out through a doorway to the bow deck.
     The array of fans on the bow is even more impressive than those on the stern. It's amazing that such a dense collection has managed to become established and grow to such size in only four years.
     They must grow much faster than similar UK species, where fans this size would be getting on for 100 years old.
     Having dipped to the seabed again, I am now very conscious of balancing my remaining air against decompression requirements. I make a brief excursion into the cabin on the main deck before ascending to the superstructure and wheelhouse. It's the kind of location where you might expect shoals of glassfish - but not today.
     It's time to move on to the wilder challenges of Tobago's sister-island.

A French angelfish waits to be cleaned on the spectacular brain coral at Kelliston Drain.


Rainbow wrasse


old barnacle shells provide homes for numerous smiling blennies


drifting along the reef at Bookends


Swimming along the deck of the Maverick off Tobago


an array of small soft corals and sponges on the underside of an elkhorn coral

GETTING THERE John Liddiard flew by British Airways scheduled direct flight to Tobago from London Gatwick. On return an £11 (approx) international departure tax must be paid in local notes. DIVING:World of Watersports at the Hilton can arrange diving all round the island, from Pigeon Point in the south to Speyside and the north coast, 001 868 660 7234, www.worldofwatersports.com. Most dives are drift dives, with delayed SMBs and reels in common use. Diving costs around £275 for a one-week package, including any equipment needed. ACCOMODATION:The Hilton Tobago is located on the beach on the south coast, halfway between the airport at Crown Point and Scarborough. Facilities include three swimming pools, fitness centre, multiple restaurants and bars, golf course and cable TV in all rooms. COST: A two-week package including flights, transfers and one week at the Hilton Tobago, one at the Hilton Trinidad, costs from £1,499 through Tropical Places, 01342 330700, www.tropical places.co.uk BEST TIME TO GO:Tobago is south of the hurricane belt. February to May are the driest months but diving is available year round. MONEY:Trinidad & Tobago dollar, exchange rate around TT$9 to the pound. US dollars widely accepted. Cash machines accept UK bank cards. TRANSPORT:Taxi from the airport to the Hilton cost around £7. Free minibus from hotel to watersports area at Pigeon Point. Shared taxis can be flagged down on the road and provide a cheap way to travel the main routes. Car rental starts at £26 per day, with an excess of £750 on any accident damage.