Unforgettable marine life encounters.

The ocean is full of wondrous creatures, but few are capable of changing your perspective on life. Gavin Bladen, captain of the 44.2m HEMISPHERE, says: ‘It’s hard to put into words the emotions you experience when you swim with a humpback whale for the first time. Humbling, a mutual respect and trust, a degree of communication, a thrill, a palpable bond, and a chance of a lifetime. If I place you in the water with a full-grown whale and her calf, you’ll be flooded with emotions that you’ll cherish for the rest of your life.’

Imagine a mother humpback and her young calf calmly hanging near the surface. After about 10 minutes, the mother decides to let her baby venture nearer. It turns sideways to make eye contact with you, and in that moment everything else fades away. It’s just you and this curious, 6m (20ft) baby humpback, eyes locked, floating together in a warm, tropical sea.

Antarctica’s snowcapped mountains and glistening ice formations, painted in a palette of blues and whites, make visiting this continent one of life’s great experiences. It is also home to one of the planet’s largest carnivores: the orca. Antarctic orcas hunt deep into pack ice for leopard seals, penguins and, sometimes, even great whales. Their remarkable intelligence makes them formidable predators. A pod of killer whales can coordinate their attack by communicating with clicks and calls; then, as they approach their prey, they become absolutely silent.

Captain Richard Callaghan recalls seeing a pod with guests on the 52.3m DENIKI. ‘They were patrolling along in the morning sunshine, their tall dorsal fins and black-and-white markings standing out against the backdrop of sea ice,’ he says. ‘The white on their sleek bodies almost glowed with red-orange hues as the sun reflected off them.’

Made up of more than 1,000 coral reef islands, the Maldives is the physical manifestation of a tropical paradise. The plankton-rich waters of this region support countless species of marine life, including the biggest fish in the sea: the whale shark. These gentle giants grow up to 12m (40ft) in length and eat as much as 45kg (90lb) of food every day. Their spot pattern appears uniform but, like a fingerprint, each one possesses distinct individual markings.

‘Of all large aquatic creatures, the whale shark is probably the most approachable,’ says the owner of 60m DREAM. ‘We’ve followed whale shark groups in DREAM’s tender and snorkelled with them as they feed. You’re looking at a fish the size of a school bus. I’ve been two feet from one’s mouth as it fed on plankton – an incredible sight.’

Indonesia is one of six countries that make up the Coral Triangle, the most biodiverse marine region anywhere in the world. The nutrient-rich waters and strong currents foster incredible species diversity and attract ocean-going animals such as manta rays. Tom Buddle, captain of the 55.7m GALILEO G, recalls manta diving in Komodo. ‘Mantas are one of my favourite animals to see underwater. These guys get up to 8m (26ft) in wingspan and can weigh 1,500kg (3,300lb). The way they glide through the water so effortlessly is always magnificent to watch. In Indonesia, it is possible to scuba, free dive and snorkel with the mantas. Minimal splashing or arm movement always assists in keeping them around the group.’

In addition to their grace, mantas have complex brains and are considered to be intelligent and self-aware even by human standards. They use rapid colour changes to communicate with each other, and display behaviours that indicate a high level of social intelligence akin to that of dolphins, chimpanzees and elephants.

The adrenaline rush you get from descending through the ocean into a school of hammerheads for the first time defies explanation. This migratory species can be found in the warm tropical waters of the Atlantic, Indian and Pacific Oceans.

Around 160km (100 miles) south of the equator, Ecuador’s remote and uninhabited Wolf and Darwin Islands attract migratory marine species and huge schools of scalloped hammerhead sharks. The islands are the remains of a huge, mostly subsurface extinct volcano that towers 1,700m (5,577ft) above the sea floor. The only visitors to their waters – other than ones with gills – are divers. According to the captain of the 37.8m STELLA MARIS, ’Guests are always in awe of the underwater experience. About 45 minutes into the dive, they encounter the sight of 300 big schooling hammerheads in around 30m (100ft) of water. At just one metre’s distance, this is an unforgettable spectacle with some of the ocean’s wildest creatures.’