Henley Spiers / Striped marlin (Kajikia audax) and California sea lion (Zalophus californianus) competing for food as they hunt down baitfish, Magdalena Bay, Baja California Sur, Mexico, Pacific Ocean.

Tui De Roy / Galapagos sea lion (Zalophus wollebaeki) yearling pup playing with own air bubbles in shallows, Gardner Islet, Espanola Island, Galapagos, Ecuador

Tui De Roy / Galapagos sea lion (Zalophus wollebaeki) pups playing at sunrise, Puerto Egas, Santiago Island, Galapagos, Ecuador

Tui De Roy / Galapagos sea lion (Zalophus wollebaeki) female and male on red volcanic beach, Rabida Island, Galapagos, Ecuador

Tui De Roy / Galapagos sea lion (Zalophus wollebaeki) female resting in shallows, Bainbridge Islets, Galapagos, Ecuador

Tui De Roy / Galapagos sea lion (Zalophus wollebaeki) pups playing in shallows, Sombrero Chino, Santiago Island, Galapagos, Ecuador

Claudio Contreras / Guadalupe fur seal (Arctocephalus townsendi) male fighting, Guadalupe Island Biosphere Reserve, off the coast of Baja California, Mexico, April

Andy Murch / Cape fur seal (Arctocephalus pusillus) playing with Dark shyshark (Haploblepharus pictus) carcass, seal diving in background. False Bay, South Africa. May.

Tui De Roy / Galapagos sea lions (Zalophus wollebaeki) sub adult males playing with starfish, Mosquera Islet, Galapagos.

Ben Cranke / King Penguins (Aptenodytes patagonicus) approached by an Antarctic Fur Seal (Arctocephalus gazella). A few pecks from the penguins caused the seal to retreat. Southern elephant seal (Mirounga leonina)...

David Hall / Steller sea lions (Eumetopias jubatus), three playing underwater, Inian Island, Alaska, USA. August.

David Hall / Steller sea lions (Eumetopias jubatus) playing underwater, Inian Island, Alaska, USA. August.

Shane Gross / Galapagos Sea Lion (Zalophus californianus wollebacki) resting on rocks at sunset on North Seymour Island, Galapagos, Ecuador. December.

Shane Gross / Galapagos sea lion (Zalophus wollebaeki) plays in the surf, San Cristobal Island, Galapagos, Ecuador. December.

Shane Gross / Galapagos sea lion (Zalophus wollebaeki) hunting shoal of Black striped salemas (Xenocys jessiae), Rabida Island, Galapagos, Ecuador. December.

Claudio Contreras / Californian sea lion (Zalophus californianus) swimming in Southern sea palm (Eisenia arborea) and Giant Kelp (Macrocystis pyrifera) forest, San Benitos Islands, Baja California Pacific Islands Biosphe...

Alex Mustard / RF - Silhouette of a California sea lion (Zalophus californianus) swimming through an underwater cave. Los Islotes, La Paz, Baja California Sur, Mexico. Sea of Cortez, Gulf of California, East Pacific...

Alex Mustard / California sea lion (Zalophus californianus) pups in an underwater cave. Los Islotes, La Paz, Baja California Sur, Mexico. Sea of Cortez, Gulf of California, East Pacific Ocean.

Jordi Chias / Antarctic fur seal (Arctocephalus gazella), Antarctic Peninsula, Antarctica.

Jordi Chias / Antarctic fur seal (Arctocephalus gazella), Antarctic Peninsula, Antarctica.

Jordi Chias / Antarctic fur seal (Arctocephalus gazella), Antarctic Peninsula, Antarctica.

Nick Hawkins / Steller's sea lions (Eumetopias jubatus) off the coast of the Great Bear Rainforest, near Bella Bella, British Columbia, Canada. August

Franco Banfi / California sealion (Zalophus californianus) swimming. Magdalena Bay, Baja California Sur, Pacific Ocean, Mexico

Nick Hawkins / Galapagos sea lion (Zalophus wollebaeki), three resting underneath school bus. Isabela Island, Galapagos. 2017.

Andy Rouse / Galapagos sea lion, (Zalophus wollebaeki), pup on shore, Galapagos.

Andy Rouse / Galapagos sea lion, (Zalophus wollebaeki), swimming upside down, Galapagos

Tui De Roy / Galapagos sea lion (Zalophus wollebaeki) killing tuna. A group of the sea lion bulls have learnt to herd Pelagic yellowfin tuna into a small cove, trapping them. The fish often leap ashore in an effor...

Tui De Roy / Galapagos sea lion (Zalophus wollebaeki) hunting tuna. A group of the sea lion bulls have learnt to herd Pelagic yellowfin tuna into a small cove, trapping them. The fish often leap ashore in an effor...

Tui De Roy / Galapagos sea lion (Zalophus wollebaeki) hunting tuna. A group of the sea lion bulls have learnt to herd Pelagic yellowfin tuna into a small cove, trapping them. The fish often leap ashore in an effor...

Alex Mustard / California sea lion (Zalophus californianus) uses a Panamic cushion star (Pentaceraster cumingi) as a toy. The sealions pick up the starfish and then drop them and chase after them as they sink. Los I...

Lucas Bustamante / Four Galapagos sea lions (Zalophus wollebaeki) sleeping on beach, Floreana Island, Galapagos, Endangered species.

Claudio Contreras / Californian Sealion (Zalophus californianus) in kelp (Macrocystis pyrifera) forest, San Benito del Este Island, Baja California Peninsula Pacific Islands Biosphere Reserve, Baja California, Mexico, Ma...

David Fleetham / California sea lions (Zalophus californianus) playing in a kelp forest off Santa Barbara Island, California, USA.

David Fleetham / California sea lions (Zalophus californianus) playing in a kelp forest off Santa Barbara Island, California, USA.

Cyril Ruoso / South American fur seal (Arctocephalus australis) coming up to beach from sea, Punta San Juan, Peru

Cyril Ruoso / South American fur seal (Arctocephalus australis) male head profile, Punta San Juan, Peru

Chris & Monique Fallows / Cape fur seal (Arctocephalus pusillus) porpoising, False Bay, Cape Town, South Africa, July.

Chris & Monique Fallows / Great white shark (Carcharodon carcharias) predating Cape fur seal (Arctocephalus pusillus) Seal Island, False Bay, South Africa, July. Sequence 3 of 3

Tony Wu / Juvenile Australian sea lion (Neophoca cinerea) silhouetted against blue skies at Carnac Island, Western Australia

Tony Wu / Juvenile Australian sea lion (Neophoca cinerea) resting in shallows, possibly to thermoregulate, Carnac Island, Western Australia.

Alex Mustard / California sea lion (Zalophus californianus) adult female swimming through sunbeams in an underwater cave. Los Isotes, La Paz, Mexico. Sea of Cortez, East Pacific Ocean.

Alex Mustard / California sea lion (Zalophus californianus) resting in the canopy of a forest of giant kelp (Macrocystis pyrifera). Santa Barbara Island, Channel Islands. Los Angeles, California, United States of Am...

Alex Mustard / Young California sea lion (Zalophus californianus) playing in the canopy of a forest of Giant kelp (Macrocystis pyrifera). Santa Barbara Island, Channel Islands. California, USA. North East Pacific Oc...

Wim van den Heever / South African fur seals (Arctocephalus pusillus pusillus) surfing out on wave.Walvisbay, Namibia.

Ben Hall / Galapagos sea lion (Zalophus wollebaeki) mother and young touching noses, Galapagos Islands, May