White rhino (Ceratotherium simum) bulls in confrontation, Zimanga private game reserve, KwaZulu-Natal, South Africa, Africa

Humpback Whale and Free Diver, Megaptera novaeangliae, Indian Ocean, Wild Coast, South Africa

An African elephant (Loxodonta africana) chases away a lion (Panthera leo) resting along its path, Savuti, Chobe National Park, Botswana, Africa

The endemic Galapagos marine iguana (Amblyrhynchus cristatus) in the Galapagos Island Archipelago, UNESCO World Heritage Site, Ecuador, South America

Adult California gray whale (Eschrictius robustus), near boat in San Ignacio Lagoon, Baja California, Mexico, North America

California gray whale calf (Eschrictius robustus), being touched by tourist in San Ignacio Lagoon, Baja California, Mexico, North America

Wild Dugong (Dugong dugong) playing with snorkeler. Kota Kinabalu, Sabah, Malaysia

Wild Dugong (Dugong dugong) taking sea grass from snorkeler. Kota Kinabalu, Sabah, Malaysia.

A heavily scarred dorsal fin of a Bottlenose Dolphin (Tursiops truncatus) tells of many encounters, some violent, with other dolphins in the Moray Firth, Scotland

Cuttlefish (Sepia officinalis) Two mating head to head within minutes of first encounter. Babbacombe, Torquay, South Devon, UK (RR)

Cleland Wildlife Park, girl feeding kangaroo, Adelaide Hills, South Australia, Australia

Portrait of a bull moose (Alces alces) walking through an alpine meadow late in the rut in Southcentral Alaska's Chugach State Park, Alaska, United States of America

Portrait of a black wolf (Canis Lupus) in the wild looking at the camera from atop a snowbank, Haines Junction, Yukon, Canada

View taken from behind of silhouettes of two blue wildebeest (Connochaetes taurinus) standing on the savanna watching a cheetah (Acinonyx jubatus) pass by, Serengeti National Park, Tanzania, Africa

Coyote (Canis latrans) walking across a wintry landscape near Val Marie, Saskatchewan, Canada

Portrait of a sunlit, wolf (Canis lupus) standing in the brush in the snow, Churchill, Manitoba, Canada

Close-up portrait of a young male lion (Panthera leo leo) lowering head, Serengeti National Park, Tanzania, Africa

Portrait of a polar bear (Ursus maritimes) standing in the snow looking at the camera, Churchill, Manitoba, Canada

Portrait of a black bear (Ursus americanus) pausing on a mountainside from feeding on lowbush cranberries and looking at the camera on a mid-October afternoon in Southcentral Alaska's Chugach Mountains, Alaska, United States of America

Close-up portrait of a Canada Lynx (Lynx canadensis) looking at the camera through the branches of a Southcentral Alaska alder thicket. Lynx populations are closely linked to booms and busts in the numbers of their main prey the snowshoe hare, Alaska, United States of America

Portrait of a male lion (Panthera leo) standing among bushes, looking mournful at the camera, Laikipia, Kenya

Portrait of a young, male lion (Panthera leo) standing on savanna, staring at the camera, licking his lips, Laikipia, Kenya

Mono, close-up portrait of a Cape Buffalo (Syncerus caffer) standing, eyeing camera in Segera, Segera, Laikipia, Kenya

Hawaii, Underwater encounters with Hawaiian monk seals (Monachus schauinslandi), endemic and endangered, are few and far between.

Hawaii, Underwater encounters with Hawaiian monk seals (Monachus schauinslandi), endemic and endangered, are few and far between.