Underwater photographer: Brian Skerry – We asked some of the world's top underwater photogs for shooting tips. They shared them in the story below, along with some of their best work in this gallery. Brian Skerry shot these spotted dolphins (Stenella frontalis) in the Bahamas.
Brian Skerry – A four-meter-long female Tiger Shark noses towards three bar jacks in the Bahamas.
Brian Skerry – A lemon shark pup swims through a mangrove nursery in Bimini.
Brian Skerry – A tiny shrimp, about half the size of a grain of rice, on a sea anemone in the Kingman Reef, which lies about 930 miles southwest of Hawaii.
Brian Skerry – A red pigfish swims through a school of blue maomao in New Zealand's Poor Knights Islands, a marine reserve.
Brian Skerry – This deep-water mangrove decorates a lagoon off the coast of Belize.
Brian Skerry – A harp seal pup makes its first swim in the icy waters of Canada's Gulf of St. Lawrence.
Brian Skerry – Soft corals called sea pens, usually found in deeper waters, and a blue cod, appear in shallow waters in New Zealand's Long Sound reserve, where tannin-stained surface water blocks sunlight.
Brian Skerry – A southern right whale (Eubalaena australis) approaches Brian Skerry's assistant off New Zealand's Auckland Islands.
David Fleetham: Underwater photographer – Hawaiian domino damselfish (Dascyllus albisella) are endemic to Hawaii.
David Fleetham – Eleven-year-old Sean Fleetham gets his first look at a day octopus, also known as the big blue octopus or octopus cyanea, off Maui, Hawaii.
David Fleetham – A green sea turtle (Chelonia mydas) rests on the sandy seabed in Hawaii.
David Fleetham – This eight-armed cephalopod was photographed in Hawaii.
David Fleetham – The dorsal fins of blacktip reef sharks (Carcharhinus melanopterus) break the surface of the island of Yap, Micronesia. Gray reef sharks (Carcharhinus amblyrhynchos) swim below.
David Fleetham – With an open mouth, a great white shark (Carcharodon carcharias) breaks the surface off Guadalupe Island, Mexico.
Adriana Basques: Executive turned diving photographer – Basques has traveled the world using her photography to communicate the importance of marine conservation. "Climate change and ocean acidification are by far the most important" conservation issues, she says.
Adriana Basques – Adriana Basques' work regularly appears in top nature magazines such as National Geographic, GEO and National Wildlife Federation.
Adriana Basques – Among the most aggressive of shark species, bull sharks live throughout the world in shallow, warm ocean waters. However, they can also adapt to swimming in freshwater rivers.
Adriana Basques – Top photo tip: "Knowing the behavior of an animal is always important," Basques says.
Adriana Basques – "Overfishing, pollution and runoff from land is strangling and killing the very source we rely upon for our survival as a species," Basques says.
Adriana Basques – Basques's advice for aspiring underwater photographers: "First of all, be an excellent diver."
Adriana Basques – Basques' work has been exhibited in the Smithsonian Museum of Natural History and her photography has been used in books, movie brochures and printed on swimwear.
Adriana Basques – Basques is particularly known for her split image photography. "I love to give people that perspective of half-land, half-ocean," she says.