Most divers will have a bucket list for marine life. After all, one of the best things about diving is meeting the underwater creatures that dwell in the blue wilderness. Certain animals, such as whale sharks, humpback whales and manta rays, consistently find their way onto the majority of divers' wish lists. However, the ocean also hides a treasure trove of lesser-known (yet equally impressive) critters. From bioluminescent aliens of the deep to sea snakes to a jellyfish lake, these obscure creatures are among the most thrilling encounters the ocean has to offer. From the obvious to the absurd, read on to discover the world's best underwater creature encounters.
Jellyfish Lake: Palau
Being flung into a lake full of jellyfish sounds less than appealing. But hear us out. In Palau, an unassuming inland lake harbours one of the most unusual underwater creature encounters in the South Pacific - if not the world. Jellyfish Lake is a 12,000-year-old marine lake located on Eil Malk Island, which is part of the Rock Islands in Palau's Southern Lagoon. Above the lake, nothing looks out of the ordinary. Yet, beneath the surface, millions of golden jellyfish migrate across the lake every day. These jellyfish have no predators, so have evolved without stingers, meaning snorkellers can join the jellyfish on their migration.
Very few divers are lucky enough to see a thresher sharks' whip-like tail sashay from the deep. With a preference for deep, dark water, these elusive sharks are rarely encountered. Yet, there is one exception to the rule, where thresher sharks can be seen on a daily basis. The Philippine island of Malapascua is the only place in the world where thresher sharks frequent diveable depths at Monad Shoal. To see these big-eyed beauties requires diving this offshore pinnacle at sunrise, but divers who make the early start are virtually guaranteed to see thresher sharks turn up for their daily clean.
Big Fish Encounters: The Galapagos, Ecuador
For those in search of big fish, the Galapagos Islands can't be beaten. As the inspiration behind Darwin's On the Origin of Species, the Galapagos Islands deserves a spot on the list of the world's best underwater creature encounters for sheer variety alone. A staggering 2,900 marine species reside in these marine-rich waters, including huge schools of scalloped hammerheads, ginormous pregnant whale sharks (July to October), dolphins, fur seals, sea lions, sea turtles, whales, rays and even the elusive mola mola (ocean sunfish). Not to mention endemic species like the rosy-lipped batfish and marine iguanas.
Marbled Grouper Spawning: French Polynesia
Each July, the Fakarava channel in French Polynesia's Tuamotu archipelago hosts one of the ocean's biggest feeding frenzies. Around the full moon in July, thousands of marbled groupers gather in the passes to lay their egg and sperm. While seeing this mass spawning is an impressive sight in itself, watching thousands of grey reef sharks turn up to feed on them is one of the ocean's greatest, and most chaotic, spectacles.
Giant Cuttlefish Migration: Australia
Between May and August, thousands of Australian giant cuttlefish migrate to Upper Spencer Gulf Marine Park in Whyalla, South Australia, to mate. Dubbed the 'masters of disguise,' cuttlefish are able to transform their appearance in a fraction of a second - a useful quirk for masking themselves from predators and luring prey. However, on this occasion, you can witness these quirky creatures put on vibrant, flashy light displays to attract a mate.
Blackwater Diving: Pico, the Azores
For those who aren't familiar with blackwater diving, it's where divers are tethered to a boat in the inky black open ocean. Unlike most night diving, which occurs on reefs, blackwater diving allows divers to experience deep sea underwater creature encounters during the diurnal migration. Pico, located on the Mid-Atlantic Ridge in the Azores archipelago, is one of the best spots for seeing all manner of translucent creatures as they rise to the surface to feed. Very lucky divers might also hear the dulcet clicks of sperm whales.
Psychedelic Frogfish: Ambon, Indonesia
The Spice Island of Ambon is one of the best muck diving locations in the world. Most of the ocean's weirdest macro critters can be found in the black sands of Ambon Bay, including bobtail squid, blue-ringed octopus, nudibranchs, bobbit worms, bamboo sharks and frogfish - including the rare psychedelic frogfish, which was first discovered here.
While you're in that neck of the woods, it would be amiss not to set sail to the Banda Sea. Another contender for the world's best underwater creature encounters, divers can see huge fevers of schooling hammerheads, blue whales and olive sea snakes.
Mantas and Whale Sharks: Hanifaru Bay, the Maldives
Every year, Hanifaru Bay, a protected UNESCO Biosphere Reserve in the Baa Atoll, hosts the world's largest aggregation of manta rays. From mid-May through to December, a back eddy (or reverse current) sucks plankton-rich water into the bay, attracting hundreds of reef manta rays in a giant feeding frenzy. While it can be easy to get caught up among the mantas, keep an eye out for whale sharks who are also known to join the buffet.
Humpbacks and Orcas: Norway
We're not going to sugarcoat it: diving in Norway during winter gets cold. But swimming alongside orcas and humpback whales under the Northern Lights more than makes up for it. Between December and February, thousands of orcas arrive in the Norwegian High Arctic to feed on giant herring bait balls, and you can join the action. Leaving dry land behind, you'll voyage to the remote fjords of northern Norway in search of this mass feeding frenzy. The icing on the cake? Finishing each day watching snow-capped fjords and goliath glaciers become inflamed in orange and pink hues during sunset.
Creatures of the Deep: Cocos Island, Costa Rica
Located in the Pacific Ocean, 340 miles offshore from Costa Rica, Cocos Island Marine Park is the best place in the world for hammerhead encounters. From June to September, divers can witness hundreds of scalloped hammerheads at the submerged seamount, Bajo Alcyone. While hammerheads are the main draw to Cocos, this remote volcanic island also harbours another shark 300 metres beneath the surface. Divers on the Undersea Hunter liveaboard can venture to 'The Wall' in search of the elusive prickly shark by DeepSee submersible. For intrepid explorers seeking unchartered territory, this is one of rarest underwater creature encounters.