BEFORE YOU CAN EVEN THINK ABOUT GETTING CLOSE to big animals, you have to find them. Many big animal sightings are seasonal due to migration, so do your research and make sure you know what to expect at various times of the year.
     Once at your destination, use the dive guides to get the most out of what could be a limited stay. They usually have a lot of experience and know the local etiquette, and you need that, because every site is different.
     Sharks and rays are most commonly seen as they approach cleaning stations - areas they must visit to have wounds, dead skin and parasites removed by the smaller fish that live at these sites.
     Virtually any fish can act as a cleaner, so dont be surprised to see angelfish or even rainbow runners approach a shark and follow it for a few metres while biting bits off it.
     In most cases sharks or rays must keep moving to oxygenate their gills, so the cleaning process may be over in a matter of seconds. But they swim circuits to revisit the station, so wait nearby and they will keep coming back.
     Never chase sharks or rays as they will swim away. Stay low.

Manta rays
Even if you have seen mantas, it may be that you have been treated only to a quick fly-past. Want to have five to 25 swirling around you for half an hour
     The best place to see mantas is when they are feeding on the surface or at cleaning stations. It is best to snorkel with them when they are feeding, but to scuba dive when they are cleaning.
     Cleaning stations give you by far the best chance to see manta rays in good numbers, for periods of up to an hour. But its important to observe the correct etiquette, or they wont come in.
     This sounds odd, but its all about allowing the ray plenty of time to get used to your presence and then settle back into a natural routine.
     I often brief my guests to look out for the cephalic (head) fins, as they tell you what the manta is thinking, and what it will probably do next!
     Tightly curled-up fins mean: Im swimming. A manta with such fins will probably simply swim past. All you can do is wait a discreet distance from the station, as unobtrusively as possible.
     If the manta decides that you pose no threat, it will uncurl its fins and start to settle down. A manta with uncurled fins is ready to sweep into the cleaning station and get down to business, so keep out of its way, and be as still as possible. If necessary, find a dead bit of reef on which to hang. Telling my guests to behave like a rock usually works.
     Placing yourself near the station for the best view while causing least interruption is important. The mantas may think you are there to be cleaned, and will move away until you get off the site. I often see mantas appear just as we get off the reef to go up to 5m!
     Try to stay downcurrent from the station, too, as youll get a better view, and your bubbles will blow away from the rays and not interrupt them.
     Mantas usually approach from the ocean (deep water) and swim into the current. They often make circuits, so if you are downcurrent from the cleaning station, they will swim past you over and over again. Once they have settled down, you can approach very carefully to take photos, but stay off the cleaning station.
     I have been observing manta behaviour for the past three years as part of a migration project. Many are gregarious and have had numerous interactions with divers and are quite happy to swim with them, but some others are very nervous.
     Each animal has its own personality. but treat them all as shy and you have a far better chance of an interaction.
     Rebreathers are clearly useful in approaching big animals, including those mantas frightened by bubbles, but some manta rays actively seek out divers bubbles.
     They wait for you to breathe out, then swim through the exhalation stream to enjoy the Jacuzzi effect!
     Dont try to touch mantas (let alone ride them) as this is guaranteed to scare them off. On occasion, they may waft past you very closely, particularly when they outnumber the divers present.
     Mantas are naturally curious and will want to take a good look at you once they are sure that no threat is present.
     When manta rays are feeding close to the surface, remain there using a snorkel and let them come to you as much as possible. They will swim into the current, then loop around and swim back to a start point. Try to work out their swimming pattern and then position yourself to best advantage.
     When there is a lot of food around, they are not bothered by snorkellers and will happily barge you out of the way!
     The greater the ratio of mantas to snorkellers, the better. A solitary manta will get spooked very quickly, but a troop of 20 will hardly notice your presence. Be prepared to swim a bit, and it is normally best to wear a wetsuit, as the plankton food usually contains lots of little stingers.

  • Top places to see manta rays include the Maldives (year round), Yap, Mexicos Sea of Cortez, Thailand and Hawaii. Most tropical areas will have a manta season or sites, but these offer the highest chance of success.

    Whale sharks
    How many times have you heard the phrase should have been with us last week when we saw a whale shark on this reef. So frustrating ! There are whale shark hotspots across the world but many are very seasonal (often down to one or two weeks per year), so make sure that youre in the right place at the right time with a good guide.
         You still have to find the sharks. Some places use spotter-planes or scouting boats, others just cruise the reefs in the usual areas. Sometimes you just get lucky and one swims past. Knowing what to expect can help you make the most of the experience.
         Whalesharks seem to come in close to the reef for cleaning and to warm up in the shallows, as well as to feed. High concentrations of plankton food mean low visibility, so you will have to work just to see them.
         Cleaning stations tend to be areas of numerous coral outcrops with attendant cleaners, or long fringing reefs with cleanerfish along their length. The whale shark will meander from one area to the next, and the actual cleaning may be imperceptible.
         Follow the guide and be vigilant. Whale sharks often patrol the reefs at the level of the drop-off, so are more likely to be found at 5m than at 30m.
         If you see one while scuba diving, it will probably be quite close because of the low visibility. You can follow it, but remember that it can swim very quickly. Also keep an eye on your depth.
         Dont swim in front of a whale sharks head, as it will scare quickly and dive down. Dont get too close to its tail, either - it can give you quite a knock if it starts to swim faster. No touching, of course!
         I have observed a whale shark turn and check out each diver in turn before continuing its swim. It then started to gulp at the exhaled bubbles of one of the divers, probably confusing them with plankton. It seemed very happy with its entourage of bubbling creatures and swam with us for another 20 minutes before heading off into the deep.
         On the surface, you will be looking for a dark shadow in contrast with the water. Polaroid sunglasses make a huge difference. Once seen, don mask, fins and snorkel and position your boat about 30m upcurrent.
         Have a spotter on the boat to direct snorkellers, and keep the boat well away from whale sharks and snorkellers.
         Slip into the water and allow the whale shark to swim to you. They are quite curious and will tolerate snorkellers as long as you dont touch them or swim down in front of them. Think no threat.
         If youre lucky, the animal will keep turning around and checking the snorkellers out. If it starts to swim to deeper water, let it go.
         When the whale shark does tolerate the snorkellers, it will keep swimming around for hours, much longer than the snorkellers can last!
         Whale sharks are often seen snacking near the surface, though most of their feeding is done in deeper water. Surface-snacking provides an ideal opportunity to snorkel, as the food will keep them shallow. They also seem to be attracted to boats of around 8-12m, perhaps because they are looking for a mate or company. A small whale shark followed our diving tender for two hours. We just kept cruising very slowly and turning the boat around when we ran out of reeftop.
         I felt very sorry for our shadow when we left her on her own.
  • Top places to see whale sharks are: the Maldives, Seychelles, Ningaloo in western Australia, Thailand, Belize, Kenya and Mozambique. Most of these have a very short season of between two weeks and two months, though the Maldives is year-round. The start of the season is often impossible to predict, so dont plan your trip solely around seeing whale sharks unless youre prepared for disappointment. If youre really lucky, you might even see one in the Egyptian Red Sea.

    Reef sharks
    A wall of 20 to 100 or more reef sharks - surely a very rare occurrence Not so, if youre in the right place. However, photographing assemblies of that size is virtually impossible, so you have to be there to know that it really happens.
         Excluding artificial feeding scenarios, the greatest concentrations of reef sharks will be found riding currents, so you need to be experienced in current diving and drift techniques, or prepared to take some instruction.
         To dive with sharks successfully, you must understand the site and its tides. It is then possible to predict where the sharks will be and whether the current will be manageable.
         The sharks will be found on ocean channel corners, or on the current points of pinnacles and submerged reefs. The usual way to dive these sites is to drop into the water upcurrent from the current point, descend quickly, drift to the areas where the sharks are, then hang on. Once you are established, the show goes on around you.
         It is best to stop behind the sharks so that you can watch them more easily, and cause less disturbance.
         Hanging on in a current is easy with a reef hook! Once you have used one, you will never consider drift-diving without one again, but they take some practice. Use a hook with about 2m of line attached, to minimise damage to the reef from inadvertent kicks or handhold changes. Anchor the hook into the base rock and not into corals, which will break and cause damage. If you cant find a suitable place, move on.
         Hang onto the line, or fix it to your BC on a low, central D-ring. If the current is tugging you onto the reef, put a little air into your BC to maintain neutral buoyancy, but remember to deflate before you unhook, or it might cause a buoyant ascent.
         Take care with your anchoring and you will not have to move at all. If used properly, a reef hook is the most reef-friendly piece of kit you will use.
         I have met many divers who have never seen a shark and initially are frightened of meeting them. Reef sharks are not remotely interested in divers as food and are far more frightened of us than the other way around.
         As soon as I show a medium-sized group of grey sharks to a novice shark diver, the fear passes and curiosity takes over. Before I know it, they are joining the group for the night dive with the feeding whitetip sharks!
         Remember: in a non-feeding situation the sharks are calm and intent only on maintaining a good position in the current. If approached, they will swim away, so it is always best to stay a little back from them and allow them to get used to your presence. They will then become more curious and come closer to take a look.
         They probably will not get as close as on a shark feed, but the sight of 100 grey sharks hanging out in the current like shark wallpaper is ample reward!
  • Top places to see reef sharks are: the Maldives, Red Sea seamounts (Elphinstone, Brothers etc), French Polynesia, Cuba, the Coral Sea.

    Oceanic sharks
    A 3m silvery body glides through the water towards you. Black, empty eyes stare at you, and in a split-second their owner turns and hurtles off into the deep, frightened by your bubbles.
         Oceanic sharks will always intrigue divers, as they are rarely seen and are big enough to make even the most experienced diver a little nervous in their presence.
         We have all seen the statistics about how few divers are attacked by sharks, but deep down, dont we just love the adrenaline hit that a big shark encounter gives us
         Oceanic sharks includes the oceanic whitetip, silky, thresher, scalloped hammerhead and blue shark. By definition, they spend most of their time over deep water and are seen regularly by divers only at the cleaning stations which they have to visit.
         All the well-known oceanic shark-spotting sites are deepwater cleaning stations. In addition, you might be lucky enough to catch a shark cruising past or attracted by nearby hunting activity.
         Despite their comparatively large size, oceanic sharks are very shy of divers, probably because of our alien smells and bubbling sounds.
         Playing a waiting game with these guys is imperative. Most success will be gained by remaining very still near a cleaning station and waiting for a visit, and this is the approach practised in Cocos and Malapascua. Rebreather use makes a real difference when trying to get closer - ask any of the professional videographers!
         The schooling behaviour of scalloped hammerheads is unusual for sharks, but gives divers a fantastic opportunity to observe large numbers at one time. Such activity is due to aggregations of females coming together in preparation for mating, and they attend cleaning stations as part of this ritual.
         At some sites you can observe the school close to the pinnacle or cleaning station. At others you must swim off the reef and wait for the school to pass you by. The sharks are sometimes curious about divers (it seems to vary with the site) and will come over to investigate, perhaps when summoned by a specific noise. Some like tank banging, but we recently summoned a school when the dive leaders depth alarm on his computer went off!
         Oceanic whitetips are often encountered cruising at or just below the surface, and are known to be equally active during the day and night. They regularly circle divers and make slow, close passes. They are not as dangerous as generally assumed but there are documented cases of attacks on swimmers, and even one diver killed.
         Many divers have seen oceanic whitetips at the Brothers and Elphinstone in the southern Egyptian Red Sea, and this has been the highlight of their dive trip. The sharks have been known to follow an SMB, and this could be used to distract them if they are getting too close for comfort.
         Under no circumstances should you enter the water if you see any oceanic shark feeding on a fish carcass. Also take extreme care in a baitball scenario.
         Silky sharks can be summoned by splashing in the water, for example by snorkelling. One on its own is manageable, but they often hunt in packs, and before long a couple more will arrive. They are very persistent and will nudge and probe snorkellers and divers on the surface to see if you respond. Make sure you do!
         We heard of three divers who got separated from their group and were floating for a couple of hours before they were picked up. They quickly attracted a group of silkies that kept prodding them, looking for an opportunity.
         The divers had to poke them back using their snorkels. One of the divers videoed the approaches, much to the consternation of his fellow-divers. If you find yourself outnumbered by curious silkies, exit the water!
  • Top places to see oceanic/deep water sharks are: Cocos, Galapagos, Red Sea seamounts (Elphinstone, Brothers etc), Mexicos Sea of Cortez and the Philippines.

    Most divers dream of diving with dolphins. Many non-divers list swimming with them as their once-in-a-lifetime ambition, so there are many dolphin interaction and activity centres around the world catering for people who want to have a close-up experience with these animals.
         Although many of these are professionally managed, the dolphins are usually held in captivity or, if they are wild, attracted to the swimmers using food bait. The experience is very artificial.
         I hate the idea of dolphins (or any large marine animal) in captivity, but finding them in the wild is very difficult.
         The trouble with dolphins is that they are just too goddamn quick and clever. The vast majority are not remotely interested in humans flailing about in the water, so they avoid us most of the time.
         That said, there are well-known places all over the world, from Scotland to New Zealand, where pods of dolphins are regularly seen and swimmers jump in for a really wild experience. Bear in mind that these sites can change from year to year as dolphins move on. Realistically, unless you are using a rebreather you have a much better chance of snorkelling than diving with dolphins, because they hate our exhaust bubbles.
         Outside of an organised tour, you will probably just come upon a pod of dolphins while out on the dive boat. Sometimes they will ride the bow wave. but sometimes they are in slow cruise mode - and then you stand a chance of snorkelling with them.
         A famous example is at Dolphin House Reef in Egypt, where a pod of spinner dolphins is regularly seen. The trick is not to bring the boats too close but to slip into the water from about 20m away and start making shallow skin dives as you swim towards the dolphins, to get them interested.
         If they are swimming quickly, forget it - youll never keep up. From personal experience resulting from many attempts to swim with dolphins, they know just how far away to stay so that you cant quite see them.
         If they are doing circuits of a reef, bide your time and catch them on their next time round. It is often the juveniles that come over to check you out before being herded back to the pod by their mums.
         Try to do something interesting, so that they become curious. Try diving down and doing a couple of somersaults. In their environment it is us that have to do the circus tricks! Youll be knackered at the end, but if they come over, its worth it!
         Note that in the open ocean, pods of dolphins often have an entourage of large oceanic sharks following them (to pick up scraps after the dolphins have been hunting). If in doubt, dont enter the water.
         I have jumped in to dive with dolphins in Cocos and quickly been surrounded by silky sharks trying to work out what all the splashing is about!
         There are places in the Bahamas where dolphins have become accustomed to humans, following many years of interaction with researchers. This is probably your best opportunity to swim with wild dolphins.
         You may be lucky enough to see a pod swim by during a dive, but your exhaust bubbles deter the dolphins from getting closer. Marine mammals use bubbles as a threat signal, so we must sound very nasty!
         A well known pod of bottlenose dolphins regularly visits Abu Nuhas in the northern Red Sea. They have been known to follow Zodiacs out to the dive sites and invite divers in for a swim.
         The interaction doesnt last long, because they get bored quickly, but it is amazing while it happens.
         The dolphins also visit divers hanging out on safety stops at the Giannis D or the other wrecks along the reef. Based on diver reports (I have asked hundreds), this is probably the best place to see wild dolphins while scuba diving.
  • Top places to see dolphins are: Red Sea (Egypt and Israel), Bahamas and pretty much anywhere where there are resident populations - including all around the UK!

  • When
    When whale sharks are snacking near the surface, slip into the water and allow them to approach you
    Using a reef-hook properly is the best way of safeguarding a reef.
    It is possible to see reef sharks in large numbers if you do your research and can handle the currents
    Do you know the difference between a manta and a mobula Both genera belong to the family Mobulidae, or devil rays, but a manta is normally big (2-4m across the wingspan, though it can grow to 7m!) and has head fins to help it when feeding or cleaning. The width across its head is about 30% of the wingspan and the mouth is at the front of the head. Mobulas tend to be smaller (usually less than 2m, though they can grow to 4m-plus) and have horns rather than head fins, about 20% of the wingspan apart. The mouth is on the underside of the head.