Two Kamchatka brown bears enjoy a bath in the cool water during hot and sunny weather with temperatures up to 35 degrees Celsius (95 Fahrenheit) at the zoo in Gelsenkirchen, Germany, Tuesday, July, 7, 2015. (Photo by Martin Meissner/AP Photo)

Two Kamchatka brown bears enjoy a bath in the cool water during hot and sunny weather with temperatures up to 35 degrees Celsius (95 Fahrenheit) at the zoo in Gelsenkirchen, Germany, Tuesday, July, 7, 2015. (Photo by Martin Meissner/AP Photo)

Seals are sleeping in the sun during hot and sunny weather with temperatures up to 35 degrees Celsius (95 Fahrenheit) at the zoo in Gelsenkirchen, Germany, Tuesday, July, 7, 2015. (Photo by Martin Meissner/AP Photo)

A polar bear enjoys a bath under the water during hot and sunny weather with temperatures up to 35 degrees Celsius (95 Fahrenheit) at the zoo in Gelsenkirchen, Germany, Tuesday, July, 7, 2015. (Photo by Martin Meissner/AP Photo)

A polar bear enjoys a bath under the water during hot and sunny weather with temperatures up to 35 degrees Celsius (95 Fahrenheit) at the zoo in Gelsenkirchen, Germany, Tuesday, July, 7, 2015. (Photo by Martin Meissner/AP Photo)

Giant Panda Hu Bao eats bamboo at Bifengxia base in Ya'an, Sichuan province, in this file photo taken September 3, 2012. Researchers have found that the giant panda is downright miserly in the amount of energy it expends on a daily basis – a level similar to that of the famously sluggish three-toed sloth – thanks to low levels of physical activity and low levels of thyroid hormones. (Photo by Reuters/China Daily)

U.S. Bureau of Land Management photo shows a sage grouse in this undated photo. A looming wildlife protection fight over the Greater Sage Grouse highlights how two environmental groups have increasingly dominated the process of species protection, sparking a backlash from pro-business Republicans. (Photo by Bob Wick/Reuters/BLM)

Felix, a 9-year-old male polar bear, looks out form a pool at the Royev Ruchey Zoo in the Siberian city of Krasnoyarsk, Russia, July 11, 2015. (Photo by Ilya Naymushin/Reuters)

Strictly Bear Dancing: The bears meet in a brief yet beautiful display of play fighting on July 2013 in Svalbard, Arctic Ocean. A pair of adolescent polar bears clash in a dramatic display of play fighting.Shot in 2013, these stunning pictures were taken by South African snapper Andrew Schoeman, 42, who was leading a photography tour across the Arctic Plains of Svalbard. The two playful beasts both stood upright and had a brief exchange which mesmerised Andrew's group.The 42-year-old, who has been taking wildlife pictures for 15 years, leads tours across the world teaching people how to photograph animals. (Photo by Andrew Schoeman/Barcroft Media)

Tiny week old California sea lion pup named Oscar seen at ZSL Whipsnade Zoo on July 03, 2015 in Bedfordshire, England. Born to first-time parents Bailey and Dominic on June 18, 2015 the two-week-old male, named Oscar is the first baby to arrive at the Zoo since dad Dominic was born in 2007. (Photo by Tony Margiocchi/Barcroft Media)

Keepers Petr Kiebel (left) and Pavel Kokert assist to cool elephants Kale and Delhi in the pool, in Usti nad Labem Zoo, Czech Republic, July 7, 2015. (Photo by Libor Zavoral/CTK/ZUMAPress)

A rare Drill monkey breed is seen at the Dvur Kralove nad Labem zoo, July 10, 2015, in Czech Republic. (Photo by David Tanecek/AP Photo)

Four week old baby Black and White Colobus Monkey “Halle” holds on to her mother Safi at the National Zoo in Canberra, Australia, 02 July 2015. (Photo by Lukas Coch/EPA)

The young seal “Thies” waiting in the seal station for its re-introduction into the wild in Friedrichskoog, Germany, July 10, 2015. (Photo by Wolfgang Runge/EPA)

A seal cool off during a heat wave in Belgrade Zoo, Serbia, Wednesday, July 8, 2015. Hot weather has set in with temperatures rising up to 38 Celsius (100,5 Fahrenheit) in Belgrade. (Photo by Darko Vojinovic/AP Photo)

Quasimodo “The World's Ugliest Dog” comes to Kimmel studio for an appearance on “Jimmy Kimmel Live!” on July 1,2015. (Photo by Cathy Gibson/Splash News)

Olive Baboons enjoying frozen ice fruit in the hot humid weather at Knowsley Safari Park in Liverpool, England on July 1, 2015. (Photo by Mirrorpix/Splash News)

Giant panda Xinxin eats her birthday cake at the panda pavilion in Seac Pai Van Park in Macau, China on July 5, 2015. Giant Panda Xinxin celebrated her eighth birthday at the panda pavilion in Seac Pai Van Park in south China's Macau on Sunday. The giant panda pair Kaikai and Xinxin was donated by the Chinese central government as gifts to Macau. (Photo by Imaginechina/Splash News)

A walruses at Hagenbeck Zoo in Hamburg, Germany on July, 7, 2015. (Photo by Werner Struss/Startraks action)