Andy Rouse / Grizzly Bear (Ursus arctos horribilis) male (right) and female fighting in water over salmon. Katmai, Alaska, USA, August.

Staffan Widstrand / Brown Bear portrait {Ursus arctos} Lapland, Finland.

Loic Poidevin / Grizzly bear (Ursus arctos horribilis) salmon fishing in river rapids, Katmai National Park, Alaska, USA

Peter Cairns / naturepl.com / European brown bear (Ursus arctos) with three cubs, Finland, June

Andy Rouse / Grizzly Bear (Ursus arctos horribilis) thrashing a large caught salmon. Katmai, Alaska, USA, August.

Danny Green / Brown Bear (Ursus arctos) portrait in water with wet fur. Finland, Europe, June.

Peter Cairns / naturepl.com / European brown bear (Ursos arctos) reflected in forest pool, Finland

Eric Baccega / Grizzly bears catching migrating salmon, Brooks river, Katmai Alaska {Ursus arctos horribilis}

Wild Wonders of Europe / Cairns / European brown bear (Ursos arctos) backlit by sun, Kuhmo, Finland, July 2009 WWE BOOK

Andy Rouse / Grizzly bear (Ursus arctos horribilis) catching salmon, Katmai NP, Alaska, USA, August

Staffan Widstrand / European Brown bear standing against tree {Ursus arctos} Lapland, Finland

Sergey Gorshkov / Two Kamchatka Brown bears (Ursus arctos beringianus) squabbling beside river, Kamchatka, Far east Russia, July

Danny Green / Brown Bear Cub (Ursus arctos) climbing tree. Finland, Europe, June.

Danny Green / Brown Bear (Ursus arctos) female scratching against tree with young cub watching. Finland, July.

Loic Poidevin / Grizzly bear (Ursus arctos horribilis) salmon fishing in river rapids, Katmai National Park, Alaska, USA

Andy Rouse / Grizzly bear (Ursus arctos horribilis) shaking dry after fishing for salmon, Katmai NP, Alaska, USA, August

Igor Shpilenok / Kamchatka Brown bear (Ursus arctos beringianus) standing whilst fishing for Salmon in Tikhaya / 'Calm' River with Kronotsky volcano, Kamchatka, Kronotsky Zapovednik Reserve, Russia.

Eric Baccega / Grizzly bear (Ursus arctos horribilis) mother with three cubs, 18 months, fishing on Brooks falls, Brooks river, Katmai National Park, Alaska, USA, July

Eric Baccega / Grizzly bear (Ursus arctos horribilis) catching salmon in Brooks river, Katmai National Park, Alaska, USA, July

Danny Green / Brown Bear (Ursus arctos) cubs, three standing in a line on their hind legs. Finland, July.

Chris Gomersall / Two European brown bear (Ursus arctos) cubs climbing pine tree in taiga forest, Martinselkonen, Finland, June

Andy Rouse / Grizzly Bear (Ursus arctos horribilis) cubs playing by a river. Katmai, Alaska, USA, September.

Diane McAllister / Two young Grizzly bear cubs (Ursus arctos horribilis) stay close together while following their mother across the Brooks River. Alaska, USA, October

Andy Rouse / Grizzly bear (Ursus arctos horribilis) cub fishing, Katmai NP, Alaska, USA, September

Andy Rouse / Silhouette of Grizzly bear (Ursus arctos horribilis) walking along river, backlit, Katmai NP, Alaska, USA, September

George Sanker / Grizzly Bear (Ursus arctos horribilis) mother with three young cubs. Grand Teton National Park, Wyoming, USA, June.

George Sanker / Grizzly Bear (Ursus arctos horribilis) mother and cubs. Grand Teton National Park, Wyoming, USA, June.

Eric Baccega / Female Grizzly bear and her two cubs (Ursus arctos horribilis) in sedge grass, Khutzeymateen Grizzly Bear Sanctuary, British Columbia, Canada, June.

Eric Baccega / Female Grizzly bear (Ursus arctos horribilis) standing up in alert and looking around, while feeding on sedge, Khutzeymateen Grizzly Bear Sanctuary, British Columbia, Canada, June.

Eric Baccega / Grizzly bear cub (Ursus arctos horribilis) resting in the sedges, Khutzeymateen Grizzly Bear Sanctuary, British Columbia, Canada, June.

Andy Rouse / Grizzly Bear (Ursus arctos horribilis) standing on hind legs in water with caught salmon. Katmai, Alaska, USA, August.

Andy Rouse / Portrait of a Grizzly Bear (Ursus arctos) cub with paw over face. Katmai, Alaska, USA, September. Not available for ringtone/wallpaper use.

Eric Baccega / Female Grizzly bear (Ursus arctos horribilis) standing up in alert and looking around, Khutzeymateen Grizzly Bear Sanctuary, British Columbia, Canada, June.

Todd Mintz / Grizzly Bear (Ursus arctos horribillis) and cub in water, play fighting. Great Bear Rainforest, British Columbia, Canada, September.

Andy Rouse / Grizzly Bear (Ursus arctos horribilis) walking through a river with caught salmon against a mountainous landscape as two gulls fly past. Katmai, Alaska, USA, August.

Sergey Gorshkov / Kamchatka Brown bear (Ursus arctos beringianus) feeding on salmon caught in river, Kamchatka, Far east Russia, July

Andy Rouse / Grizzly bear (Ursus arctos horribilis) leaping through water chasing salmon, Katmai NP, Alaska, USA, September, (01360399 is a crop of this image)

Paul Hobson / Brown bear (Ursus arctos) two grazing beside water, Finland, June

Edwin Giesbers / Big close up of the eyes of a European Brown bear (Ursus arctos) captive

Nick Garbutt / Black bear {Ursus americanus} feeding on fish, Princes Royal Island, Great Bear Rainforest, British Columbia, Canada.

Bertie Gregory / Vancouver Island Black bear (Ursus americanus vancouveri) yearling portrait, Vancouver Island, British Columbia, Canada, August.

Matthew Maran / Black bear (Ursus americanus) scratching its head. Clayoquot Sound, Vancouver Island, Canada

George Sanker / Cinnamon bear, subspecies of black bear (Ursus americanus cinnamomum) cub in tree. Yellowstone National Park, Wyoming, USA, May.

Tom Vezo / Black bear cub {Ursus americanus} captive Montana USA.

Eric Baccega / Black bear cub (18m-old) climbing tree {Ursus americanus} Quebec, Canada.

Edwin Giesbers,Edwin Giesbers / Asiatic black / Moon bear (Ursus thibetanus) head portrait with tongue hanging out, captive

George McCarthy / Black Bear {Ursus americanus} relaxing on the edge of a small stream, Alaska, USA

George Sanker / Cinnamon bear, subspecies of black bear (Ursus americanus cinnamomum) cub climbing tree, Yellowstone National Park, Wyoming, USA, May.

George Sanker / Cinnamon bear, subspecies of Black bear (Ursus americanus cinnamomum) Mother with young cub. Yellowstone National Park, Wyoming, USA, May.

Charlie Summers / Black Bear (Ursus americanus) with Pink Salmon (Oncorhynchus gorbuscha) catch, Anan Creek, Alaska, July.

Bertie Gregory / Vancouver Island black bear (Ursus americanus vancouveri) yearling attempting to eat a starfish on a beach, Vancouver Island, British Columbia, Canada, July.

Eric Baccega / Head portrait of Asiatic black bear (Ursus thibetanus) at the Chengdu rescue centre of the Animal Asia Foundation, Sichuan, China September 2008

Edwin Giesbers / Two Asiatic black / Moon bears (Ursus thibetanus) rolling on the ground playing fighting together, captive; Isselburg zoo; Germany.

Edwin Giesbers / Asiatic black / Moon bear (Ursus thibetanus) sitting on grass, holding large tree branch, captive; Isselburg zoo; Germany.

Ole Jorgen Liodden / Polar Bear (Ursus maritimus) looking across ice floe seascape. Nordaustlandet, Svalbard, August.

Steven Kazlowski / Polar bear (Ursus maritimus) curious cub sits up on its hind legs, paw raised, and tries to balance itself, along Bernard Spit in autumn, 1002 area of the Arctic National Wildlife Refuge, Alaska, US...

Suzi Eszterhas / Polar Bear {Ursus maritimus} 3/4-months cubs peeking over mother who has been anaesthetised by biologists, Wapusk NP, Manitoba, Canada

Steven Kazlowski / Young Polar bear (Ursus maritimus) standing and trying to balance in shallow water along the Bernard Spit, 1002 area of the Arctic National Wildlife Refuge, North Slope of the Brooks Range, Alaska, Oc...

Steven Kazlowski / Polar bear (Ursus maritimus) in sea off Bernard Spit, 1002 area of the Arctic National Wildlife Refuge, North Slope of the Brooks Range, Alaska, September 2011

Kevin Schafer / Polar bear (Ursus maritimus) sleeping on pack ice, Svalbard, Arctic Norway, vulnerable species 2010

Steven Kazlowski / Polar bear (Ursus maritimus) cub in newly forming pack ice with the mother sitting on the shore, Arctic coast, Alaska

Wild Wonders of Europe / Liodden / Polar bear (Ursus maritimus) in front of glacier, Spitsbergen, Svalbard, March 2009

Steven Kazlowski / Polar bear (Ursus maritimus) sow standing with her cub outside their den in late winter, Arctic coast of Alaska

Andy Rouse / Polar Bear (Ursus maritimus) mother and cub (18 months) walking away after swimming, Svalbard, Norway (non-ex). This image is a crop of 01262710.

Eric Baccega / Polar bear cub 3 months (Ursus maritimus) playing in the front of the day den in march. Wapusk National Park. Churchill, Manitoba, Canada

Steven Kazlowski / Polar bear (Ursus maritimus) 3-year-olds play fighting on newly formed pack ice, Beaufort Sea, off the 1002 area of the Arctic National Wildlife Refuge, North Slope, Alaska

Andy Rouse / Polar bear (Ursus maritimus) new year cub, 6 months, standing on hind legs, Svalbard, Norway (non-ex) July 2007

Suzi Eszterhas / Polar Bear {Ursus maritimus} 3/4-months cub huddled over mother who has been anaesthetised by biologists, Wapusk NP, Manitoba, Canada~(Digitally removed mother's ear tags)

Steven Kazlowski,Steven Kazlowski / Polar bear (Ursus maritimus) juvenile spreading body weight over thin newly forming pack ice, trying not to break through, Beaufort Sea, off the 1002 area of the Arctic National Wildlife Refuge, North...

Steven Kazlowski / Polar bear (Ursus maritimus) sow plays with her spring cub outside their den in late winter, Alaska

Roy Mangersnes / Polar bear (Ursus maritimus) sitting with dark blue tongue showing, Spitsbergen, Svalbard, Norway, August

Andy Rouse / Polar Bear (Ursus maritimus) mother with cubs in snow hollow, Canadian Arctic (non-ex)

Andy Rouse / Polar Bear (Ursus maritimus) mother standing on hind legs, and cub (18 months old). Svalbard, Norway, Europe, February.

Steven Kazlowski / Polar bear (Ursus maritimus) sow and cub sliding on their backs over the pack ice, much like ice skating, 1002 coastal plain of the Arctic National Wildlife Refuge, Alaska, USA

Steven Kazlowski / Polar bear (Ursus maritimus) female practises breaking a hole in the pack ice, in the 1002 coastal plain of the Arctic National Wildlife Refuge, Alaska, USA

Steven Kazlowski / Polar bear {Ursus maritimus} at truck window, mouth open Coastal plain of the Arctic National Wildlife Refuge, Alaska. Note black tongue

Steven Kazlowski / Polar bear (Ursus maritimus) head close-up portrait of an adult male, with snowflakes on fur, Barter Island, 1002 area of the Arctic National Wildlife Refuge, Alaska

Steven Kazlowski / Polar bear (Ursus maritimus) adult swims in waters along Spitsbergen and the northwestern coast of the Svalbard Archipelago, Norway, Greenland Sea, July

Rod Williams / Sloth bear {Melursus ursinus} female portrait. Captive. Sri Lanka.

Axel Gomille / Sloth Bear (Melursus ursinus) foraging on rocks. Karnataka, India, March.

Axel Gomille / Sloth bear (Melursus ursinus) mother with cub on her back, India

Axel Gomille / Portrait of a young adult male Sloth Bear (Melursus ursinus) standing on hind legs by a rock. Karnataka, India, March.

Axel Gomille / Sloth Bear (Melursus ursinus) cub riding on its mother's back. Karnataka, India, April.

Axel Gomille / Sloth bear (Melursus ursinus), old male, India

Axel Gomille / Sloth Bear (Melursus ursinus) mother with cub riding on her back. Karnataka, India, April. Did you know? The sloth bear is the only bear that carries its young on its back.

Axel Gomille / Sloth Bear (Melursus ursinus) mother with cubs. Karnataka, India, March.

Anup Shah / Malayan sun bear {Ursus malayanus}

Edwin Giesbers / Malayan Sun Bear (Ursus malayanus) head portrait. Capitve, native to southeast Asia. Vulnerable

Mark Carwardine / Malayan sun bear (Ursus malayanus) with long tongue sticking out, captive, near Phnom Penh, Cambodia, Endangered or threatened species (Vulnerable)

Eric Baccega / Malayan Sun bear {Helarctos / Ursus malayanus} portrait, captive.