1. Whale Shark
The largest fish in the ocean, a whale shark can grow to 14 meters or more — about the size of a typical Manhattan apartment. The whale shark population is decreasing, thanks in large part to the shark-fin trade. So far, the whale shark is “only” listed as a vulnerable species.
Wolf Island or Darwin Island, Galapagos, Ecuador
When: June – November
Get there: The Galapagos are 620 miles off the coast of Ecuador. Tourism is strictly but randomly controlled and regulations change frequently. Easiest is to book a live-aboard dive boat, well in advance. Otherwise, take your chances with dive shops on San Cristobal Island, who may or may not be able to get you to Wolf and Darwin Islands.
Zanzibar, Tanzania (Manta Reef)
When: November – March
Get there: Zanzibar is an island off the coast of Tanzania in southeast Africa. Ferries from Dar es Salaam, the capital, run frequently and take about 1.5 hours. Flights are more expensive, especially with added baggage fees if you bring your own gear.
Thailand (Hin Daeng or Richelieu Rock)
When: March – May
Get there: Dive shops on Koh Phi Phi and Koh Lanta run day trips to Hin Daeng. Richelieu Rock, in the Surin Islands, can only be reached by live-aboards out of Phuket, Khao Lak, or Ranong.
AirAsia has cheap flights from Bangkok and Kuala Lumpur to Phuket and Krabi (for ferries to Koh Lanta and Koh Phi Phi), though baggage overage will add to the cost if you bring your own.
Exmouth, Australia (Ningaloo Reef)
When: March – April
Get there: During tourist season, buses run from Perth (about 15 hours) and Broome (about 16 hours) in Western Australia. If you’re in a rush, SkyWest does daily two-hour flights from Perth.
Placencia, Belize (The Gladden Cut)
When: April – June
Get there: Tropic Air and Maya Island Air have flights from Belize City. Flights are often canceled if they aren’t full enough, but this shouldn’t be a problem during tourist season.
Donsol, Philippines (snorkeling only)
When: November – May
Get there: Philippine Airlines flies from the capital of Manila to Legaspi City. From Legaspi to Donsol, either take a cheap private van (aircon, leaves right away), or a ridiculously cheap public van (chickens, open windows, leaves when overstuffed).
2. Great White Shark
Great Whites are teeny compared to whale sharks. They only grow to about 6 meters, a mere 3.5 times bigger than I am. But as they are extremely aggressive, the only rational choice for seeing them underwater is from within a cage.
Like many sharks, Great Whites are on the list of vulnerable species.
Gansbaai, South Africa
When: Year round; best March – September
Get there: Contact your shark-dive operator to arrange transport to Gansbaai, a two-hour drive from Cape Town.
Port Lincoln, Australia
When: August – November, January – March
Get there: Port Lincoln is an eight-hour drive from Adelaide, in southeastern Australia. Most divers take a puddle-jumper from Adelaide on Regional Express or Quantas.
Farallon Islands, California
When: September – November
Get there: Most dive trips leave from San Francisco and the Bay Area.
3. Hammerhead Shark
There are nine known species of hammerhead, most of which are either endangered (scalloped and great hammerheads) or vulnerable. The only kind of shark that schools, these relatively shy creatures typically run around 4 meters long.
Wolf Island and Darwin Island, Galapagos
When: Year round; best June – November
Get there: See info for the whale shark above.
Layang Layang, Malaysia
When: February – October
Get there: Layang Layang is a small island off the northern coast of Malaysian Borneo. There’s one place to stay, and the only thing to do is dive.
Malpelo Island, Colombia; Cocos Island, Costa Rica
When: June – November; July is best
Get there: These two islands are about 380 miles apart, situated in the Pacific Ocean between Costa Rica and Colombia. Live-aboards originating in Colombia, Panama, and Costa Rica can include stops at one or both.
In theory, a day trip to Malpelo can be arranged from Guapi, Colombia, though given the distance (235 miles) I imagine it would be a long, frustrating day.
KwaZulu Natal, South Africa (Protea Banks)
When: Year round; June is best
Get there: Most divers fly into Durban. The only direct international flight from outside Africa is on Emirates, from Dubai. Otherwise, Kulula Airlines flies from Johannesburg.
Tahiti, French Polynesia (Rangiroa atoll)
When: January – February
Get there: Air Tahiti connects Rangiroa to other parts of the archipelago, including the capital of Papeete on Tahiti island.
4. Mola Mola
The mola mola, or ocean sunfish, looks like a 2-meter serving platter with fins. They are shy, deepwater fishes, so it’s extremely rare to see them while diving (as opposed to seeing them from the dive boat in open water).
Bali, Indonesia (Crystal Bay at Nusa Penida, Mimpang, Nusa Lembogan)
When: July – October
Get there: The international airport on Bali is in Denpasar. AirAsia runs cheap flights from Bangkok, Kuala Lumpur, and other Southeast Asian hubs.
Most dive trips to Nusas Penida and Lembogan leave from the coastal town of Sanur, which is a two-hour minivan ride from Denpasar.
Galapagos, Ecuador (Punta Vicente Roca)
When: Year round
Get there: See info above for the Galapagos.
5. Manta Ray
The largest of all rays at up to 6 meters, mantas are also the most popular. According to my careful observations, one in three dive shops uses a manta in its logo. Buyer beware: “Manta Point” is probably the most misleading dive site name in the world.
Bali, Indonesia (Manta Point at Nusa Penida)
When: Year round; best April – May
Get there: See info above for Nusa Penida.
Similan Islands, Thailand (Koh Bon)
When: November – April
Get there: Like Richelieu Rock, Koh Bon can only be reached by live-aboards out of Phuket, Khao Lak, or Ranong.
When: Year round
Get there: Another archipelago nation, the Maldives are located in the Indian Ocean off the southwest coast of India.
The international airport in the capital of Male is served by many operators from Southeast Asia, Dubai, and Europe. The diving improves, naturally, the farther you get from Male.
6. Pygmy seahorse
At the other end of the size spectrum, the maximum dimension of a pygmy seahorse is about 2.4cm. They’re seen most often — usually only after your divemaster has found one for you — in the sprawling Indonesian archipelago. They are a vulnerable species.
Sulawesi, Indonesia (Wakatobi, Lembeh Straights)
When: Year round
Get there: A remote group of islands in the remote Indonesian province of Sulawesi, Wakatobi can be reached by either a live-aboard or a charter flight from Bali.
Pulau Weh, Aceh, Indonesia
When: Year round
Get there: Regular ferries run between Banda Aceh, the capital of Aceh province, and the island of Pulau Weh.
Bali, Indonesia (Tulamben)
When: Year round
Get there: From Denpasar, rent a car or take a minivan to Amed. At one of the many local dive shops, ask to dive the Liberty Wreck at Tulamben.
From there, take a shared taxi to Semporna, and then a speedboat to Mabul. All this can be arranged in advance by one of the local dive shops.
There are plenty more creatures in Photo Essay: The Matador Photographers’ Animal Kingdom.