Alex Mustard / Oceanic whitetip shark (Carcharhinus longimanus) swimming close to surface. Brothers Islands, Egypt.

Shane Gross / Caribbean reef shark (Carcharhinus perezi), two from below, one close up. Caribbean Sea off Gardens of the Queen National Park, Cuba.

Tony Wu / Blacktip reef shark (Carcharhinus melanopterus) beaching itself to catch sardines. Tonga South Pacific.

Alex Mustard / Blacktip reef shark (Carcharhinus melanopterus) swims through schools of fish. Misool, Raja Ampat, West Papua, Indonesia. Ceram Sea. Tropical West Pacific Ocean.

Nick Hawkins / Blue shark (Prionace glauca) with a pair of pilot fish (Naucrates ductor) off Halifax, Nova Scotia, Canada. July.

Nick Hawkins / Blue shark (Prionace glauca) off Halifax, Nova Scotia, Canada. July.

Nick Hawkins / Overhead view of a blue shark (Prionace glauca) off Halifax, Nova Scotia, Canada. July.

Pascal Kobeh / Blue shark (Prionace glauca) Azores, Atlantic Ocean.

Nick Hawkins / Silky shark (Carcharhinus falciformis). Cocos Island National Park, Costa Rica.

Shane Gross / Lemon shark pup (Negaprion brevirostris) in mangrove forest which acts as a nursery for juveniles of this species. Eleuthera, Bahamas.

Shane Gross / Lemon shark pup (Negaprion brevirostris) in mangrove forest which acts as a nursery for juveniles of this species. Eleuthera, Bahamas.

Shane Gross / Lemon shark pup (Negaprion brevirostris) in mangrove forest which acts as a nursery for juveniles of this species. Eleuthera, Bahamas.

David Fleetham / Blacktip reef shark (Carcharhinus melanopterus) swimming just below surface at sunset, split level view. Off the island of Yap, Micronesia.

David Fleetham / Whitetip reef shark (Triaenodon obesus) resting on sea floor. Kauai, Hawaii.

Jeff Rotman / Head and gills of juvenile Scalloped hammerhead shark (Sphyrna Lewini), Kane'ohe Bay, Hawaii, Pacific Ocean.

Claudio Contreras / Black grouper (Mycteroperca bonaci) and Caribbean Reef Shark (Carcharhinus perezi), Jardines de la Reina / Gardens of the Queen National Park, Caribbean Sea, Ciego de Avila, Cuba, January

Claudio Contreras / Silky shark (Carcharhinus falciformis) two swimming together, Jardines de la Reina / Gardens of the Queen National Park, Caribbean Sea, Ciego de Avila, Cuba, January. Vulnerable species.

Doug Perrine / Female scalloped hammerhead shark, Sphyrna lewini, off Keauhou, South Kona, Big Island, Hawaii, USA ( Central Pacific Ocean )

Doug Perrine / Female scalloped hammerhead shark, (Sphyrna lewini) off Keauhou, South Kona, Big Island, Hawaii, Central Pacific Ocean

Alex Mustard / Great hammerhead shark (Sphyrna mokarran) female at night with Bar jacks (Caranx ruber), South Bimini, Bahamas. The Bahamas National Shark Sanctuary. Gulf Stream, West Atlantic Ocean.

Alex Mustard / Great hammerhead shark (Sphyrna mokarran) male in shallow water. South Bimini, Bahamas. The Bahamas National Shark Sanctuary. Gulf Stream, West Atlantic Ocean.

Alex Mustard / Great hammerhead shark (Sphyrna mokarran) swimming over a sandy seabed, accompanied by Rainbow runners (Elagatis bipinnulata) South Bimini, Bahamas. The Bahamas National Shark Sanctuary. Gulf Stream,...

Alex Mustard / Whitetip shark (Carcharhinus longimanus) head on beneath the surface. Rocky Island, Egypt. Red Sea

Alex Mustard / Diver (Predrag Vuckovic) is dwarfed by Great hammerhead shark (Sphyrna mokarran). This species can reach over 6m in length. South Bimini, Bahamas. The Bahamas National Shark Sanctuary. Gulf Stream, We...

Jordi Chias / Split level view of Blue shark (Prionace glauca) at surface at sunset, Azores Islands, Portugal, Atlantic Ocean

Franco Banfi / Tiger shark (Galeocerdo cuvier) Northern Bahamas, Caribbean Sea, Atlantic Ocean.

Franco Banfi / Scuba diver and Tiger shark (Galeocerdo cuvier) Northern Bahamas, Caribbean Sea, Atlantic Ocean. March 2009.

Franco Banfi / Lemon shark (Negaprion brevirostris) Northern Bahamas, Caribbean Sea, Atlantic Ocean

Franco Banfi / Schooling Scalloped hammerhead sharks (Sphyrna lewini) Cocos Island National Park, Costa Rica.

Claudio Contreras / Bull shark (Carcharhinus leucas) Playa del Carmen, Caribbean Sea, Mexico, January.

Richard Robinson / Blue shark (Prionace glauca) just below surface, Hauraki Gulf, Auckland, New Zealand, June.

Richard Robinson / Blue shark (Prionace glauca) viewed from below, off the coast of Hawke's Bay, New Zealand, February.

Richard Robinson / Blue shark (Prionace glauca) worked from below with rays of sun, off the coast of Hawke's Bay, New Zealand, February.

Richard Robinson / A Blue shark (Prionace glauca) just below the surface, with nictitating membrane partially shut to protect its eye, Hauraki Gulf, Auckland, New Zealand, June.

Alex Mustard / Oceanic whitetip shark (Carcharhinus longimanus) accompanied by pilotfish (Naucrates ductor) as it cruises beneath the surface of the Red Sea, close to Little Brother Island. The Brothers Islands, Egy...

Pascal Kobeh / Sicklefin lemon shark (Negaprion acutidens) in the lagoon of Picard Island, Aldabra, Seychelles, Indian Ocean.

Pascal Kobeh / Scalloped hammerhead (Sphyrna lewini), Cocos Island , Costa Rica. Pacific Ocean.

Alex Mustard / Blue sharks (Prionace glauca) cruise beneath the surface of the English Channel. Penzance, Cornwall, England, British Isles. North East Atlantic Ocean, August. Winner of the Coast and Marine category...

Flip Nicklin / Bull Shark (Carcharhinus leucas), North America

Pascal Kobeh / White tip shark (Triaenodon obesus) laying on the sandy bottom, New Caledonia, Pacific Ocean.

Alex Mustard / Blacktip reef sharks (Carcharhinus melanopterus) circling over a shallow coral garden (Acropora spp.). Misool, Raja Ampat, West Papua, Indonesia. Misool Marine Protected Area. Ceram Sea. Tropical West...

Sergio Hanquet / Blue shark (Prionace glauca). Canary Islands. North Atlantic Ocean.

Sergio Hanquet / Blue shark (Prionace glauca). North Atlantic Ocean, Canary Islands.

Shane Gross / Caribbean reef shark (Carcharhinus perezi) swimming over Coral reef. Eleuthera, Bahamas.

Shane Gross / Caribbean reef shark (Carcharhinus perezi) and Horse eye jack (Caranx latus) shoal silhouetted underneath catamaran boat, Bahamas.

Shane Gross / Great hammerhead shark (Sphyrna mokarran) swimming along coral reef wall. Exuma Cays Land and Sea Park, marine protected area, Bahamas.

Shane Gross / Caribbean reef shark (Carcharhinus perezi) swimming over Manatee grass (Syringodium filiforme). Nassau, Bahamas.

Shane Gross / Blacknose shark (Carcharhinus acronotus) group in a mating aggregation. The Bahamas.

Shane Gross / Caribbean reef shark (Carcharhinus perezi) swimming along edge of blue hole. Bahamas.

Shane Gross / Caribbean reef shark (Carcharhinus perezi) in Caribbean Sea off Gardens of the Queen National Park, Cuba.

Shane Gross / Silky shark (Carcharhinus falciformis). Caribbean Sea off Gardens of the Queen National Park, Cuba.

Shane Gross / Silky shark (Carcharhinus falciformis), three in open ocean. Caribbean Sea off Gardens of the Queen National Park, Cuba.

Shane Gross / Caribbean reef shark (Carcharhinus perezi) swimming over coral reef, silhouetted. Caribbean Sea off Gardens of the Queen National Park, Cuba.

Shane Gross / Caribbean reef shark (Carcharhinus perezi) patrolling coral reef with Schoolmaster snapper (Lutjanus apodus) and other fish. Caribbean Sea off Gardens of the Queen National Park, Cuba.

Shane Gross / Coral reef wall with sponges, Caribbean reef shark (Carcharhinus perezi) in background. Caribbean Sea off Gardens of the Queen National Park, Cuba.

Shane Gross / Caribbean reef shark (Carcharhinus perezi) swimming over coral reef. Caribbean Sea off Gardens of the Queen National Park, Cuba.

Shane Gross / Silky shark (Carcharhinus falciformis), three in Caribbean Sea off Gardens of the Queen National Park, Cuba.

Pascal Kobeh / Close-up of the head of a White tip shark (Triaenodon obesus) laying on the bottom with a Remora (Echeneis naucrates) on its head, Sulu sea, Philippines

Alex Mustard / Blacktip reef shark (Carcharhinus melanopterus) swims beneath a jetty and schools of silversides (Atherinidae) on a coral reef. Misool, Raja Ampat, West Papua, Indonesia. Ceram Sea. Tropical West Paci...

Alex Mustard / Few fish from a school of Bigeye trevally (+Caranx sexfasciatus) break off to scratch themselves against the flank of a blacktip reef shark (Carcharhinus melanopterus). This is a common and world wide...

Tony Wu / Blacktip reef shark (Carcharhinus melanopterus) slicing through shallow water in pursuit of sardines, some of which can be seen jumping into the air to avoid being caught. Tonga, Pacific Ocean.

Alex Mustard / Scalloped hammerhead shark (Sphyrna lewini) swims through a school of Pacific creolefish (Paranthias colonus). Wolf Island, Galapagos National Park, Galapagos Islands.. East Pacific Ocean.

Alex Mustard / Lemon shark (Negaprion brevirostris) in snell's window. Grand Bahama. Bahamas. The Bahamas National Shark Sanctuary. Little Bahama Bank, West Atlantic Ocean.

Nick Hawkins / Blue shark (Prionace glauca) with pilot fish (Naucrates ductor) off Halifax, Nova Scotia, Canada. July.

Nick Hawkins / Blue shark (Prionace glauca) off Halifax, Nova Scotia, Canada. July.

Nick Hawkins / Blue shark (Prionace glauca) off Halifax, Nova Scotia, Canada. July.

Nick Hawkins / Blue shark (Prionace glauca) with a pair of pilot fish (Naucrates ductor) off Halifax, Nova Scotia, Canada. July.

Nick Hawkins / Blue shark (Prionace glauca) off Halifax, Nova Scotia, Canada. July.

Nick Hawkins / Blue shark (Prionace glauca) off Halifax, Nova Scotia, Canada. July.

Nick Hawkins / Blue shark (Prionace glauca) off Halifax, Nova Scotia, Canada. July.

Shane Gross / Scuba diver feeds an invasive lionfish (Pterois volitans) to a Caribbean reef shark (Carcharhinus perezi) off Grand Bahama Island, Bahamas. It was once thought that if the sharks learned that lionfish...

Shane Gross / Scuba diver feeds an invasive lionfish (Pterois volitans) to a Caribbean reef shark (Carcharhinus perezi) off Grand Bahama Island, Bahamas. It was once thought that if the sharks learned that lionfish...

Shane Gross / An invasive lionfish (Pterois volitans) is fed to a Caribbean reef shark (Carcharhinus perezi) off Grand Bahama Island, Bahamas. It was once thought sharks could be trianed to feed on lionfish by feed...

Shane Gross / Queen conch (Lobatus gigas) moving along the ocean floor with Caribbean reef sharks (Carcharhinus perezi) in the background. Image made off Grand Bahama Island, Bahamas.

Pascal Kobeh / Blue shark (Prionace glauca) Azores, Atlantic Ocean.

Pascal Kobeh / Blue shark (Prionace glauca) with divers filming or photographing it, Azores, Atlantic Ocean.

Pascal Kobeh / Blue shark (Prionace glauca) with divers filming or photographing it, Azores, Atlantic Ocean.

Pascal Kobeh / Blue shark (Prionace glauca) with divers filming or photographing it, Azores, Atlantic Ocean.

Pascal Kobeh / Blue shark (Prionace glauca) with divers, Azores, Atlantic Ocean.

Pascal Kobeh / Blue shark (Prionace glauca) with divers, Azores, Atlantic Ocean.

Pascal Kobeh / Close-up of Blue shark (Prionace glauca) Azores, Atlantic Ocean. Medium repro only

Nick Hawkins / Whitetip reef shark (Triaenodon obesus) resting during daytime on sea floor. Near Cocos Island National Park, Costa Rica.

Nick Hawkins / Whitetip reef shark (Triaenodon obesus) resting during daytime on sea floor. Cocos Island National Park, Costa Rica.

Shane Gross / Lemon shark pup (Negaprion brevirostris) in mangrove forest which acts as a nursery for juveniles of this species. Eleuthera, Bahamas.

Shane Gross / Lemon shark pup (Negaprion brevirostris) in mangrove forest which acts as a nursery for juveniles of this species. Eleuthera, Bahamas.

Shane Gross / Lemon shark pup (Negaprion brevirostris) in mangrove forest which acts as a nursery for juveniles of this species. Eleuthera, Bahamas.

Shane Gross / Lemon shark pup (Negaprion brevirostris) in mangrove forest which acts as a nursery for juveniles of this species. Eleuthera, Bahamas.

Shane Gross / Lemon shark pups (Negaprion brevirostris) spend the first 5-8 years of their life in mangrove forests. The tangle of roots provides protection from predators and is full of potential prey like juvenil...

Shane Gross / Lemon shark pups (Negaprion brevirostris) spend the first 5-8 years of their life in mangrove forests. The tangle of roots provides protection from predators and is full of potential prey like juvenil...

Shane Gross / Researchers test whether a lemon shark pup (Negaprion brevirostris) had been previously tagged at the Cape Eleuthera Insitute, Bahamas. September 2015

Shane Gross / Researchers test whether a lemon shark pup (Negaprion brevirostris) had been previously tagged at the Cape Eleuthera Insitute, Bahamas. September 2015

Shane Gross / Lemon shark pup (Negaprion brevirostris) in mangrove forest which acts as a nursery for juveniles of this species. Eleuthera, Bahamas.

Shane Gross / Lemon shark (Negaprion brevirostris) adult resting and allowing a small cleaner wrasse feed off parasites. Grand Bahama Island, Bahamas.

Shane Gross / Lemon shark pup (Negaprion brevirostris) in mangrove forest which acts as a nursery for juveniles of this species. Eleuthera, Bahamas.

Shane Gross / Lemon shark pup (Negaprion brevirostris) in mangrove forest which acts as a nursery for juveniles of this species. Eleuthera, Bahamas.

Shane Gross / Lemon shark pup (Negaprion brevirostris) in mangrove forest which acts as a nursery for juveniles of this species. Eleuthera, Bahamas.