Young Polar bear Anori plays with his toys in the pool of their enclosure at the Zoo in Wuppertal, Germany, Wednesday, April 16, 2014 as spring weather arrives in Germany with temperatures up to 19 degrees Celsius (66 Fahrenheit) and continuous sunshine. (Photo by Frank Augstein/AP Photo)

Bennett's tree-kangaroo Alberta carries her baby in her pouch on April 16, 2014 at the Marlow animal park in Marlow, eastern Germany. Albino kangaroo Alberta is one of the most famous residents of the park. (Photo by Bernd Wuestneck/AFP Photo)

An Iraqi boy jumps in the water near cows south of Iraq's central Shiite Muslim Shrine city of Najaf on April 14, 2014. (Photo by Haidar Hamdani/AFP Photo)

The Bundy family and their supporters fly the American flag as their cattle were released by the Bureau of Land Management back onto public land outside of Bunkerville, Nev. on April 12, 2014. (Photo by Jason Bean/AP Photo/Las Vegas Review-Journal)

The spring sun lights the face of a chimpanzee eating in his outdoor quarters at Artis Royal Zoo in Amsterdam, Netherlands, Wednesday, April 16, 2014. (Photo by Peter Dejong/AP Photo)

A visitor prepares to take a picture of three red ruffed lemurs sitting on a fence to take in the warmth of the spring sun, at Artis Royal Zoo in Amsterdam, Netherlands, Wednesday, April 16, 2014. (Photo by Peter Dejong/AP Photo)

Visitors watch lions playing in the Taigan Safari Park, about 50 km (31 miles) east of Simferopol, Crimea, Saturday, April 12, 2014. The Taigan Safari Park, created in 2012, is home to some 50 lions and a unique attraction in Eastern Europe. Visitors have the opportunity to see lions on the range as the park is equipped with special observation decks with total length of one kilometer. They allow admiring the lions from safe distance. (Photo by Alexander Polegenko/AP Photo)

Zoo keeper Thomas Feierabend carries a kangaroo baby named Josey as the zoo hold their annual inventory at the Hagenbeck zoo in Hamburg on April 11, 2014. (Photo by Maja Hitij/AFP Photo/DPA)

A one-week young camel, named Ilias, is cleaned by its eight-year old mother, Iris, in Budapest Zoo and Botanic Garden on April 15, 2014. The small animal was born on April 8. (Photo by Attila Kisbenedek/AFP Photo)

In December born male zebra Jambo, left, plays with it's mother as it is enjoying the outdoor enclosure while shown to public for the first time at the Zoo in Wuppertal, Germany, Wednesday, April 16, 2014. (Photo by Frank Augstein/AP Photo)

Elizabeth Knoll, from the U.S., enjoys feeding jackdaws during misty weather on the Pilatus mountain near Alpnachstad, Switzerland, on April 18, 2014. (Photo by Alexandra Wey/Keystone)

The head of a hen is seen before being sacrificed during Bisket Jatra festival in Bhaktapur district, Nepal, 13 April 2014. Hundreds of Newar community devotees tilted up the 35 feet tall wooden pole on occasion of the traditional Bisket Jatra festival which is celebrated during the Nepali New Year in Bhaktapur. The pole is believed to protect from all natural calamities and supports a good harvest for coming year. (Photo by Narendra Shrestha/EPA)

Zoo spokesman Ron Magill holds a flaming during a roundup of Caribbean Flamingos at Zoo Miami in Miami, Thursday, April 17, 2014. The flamingos are being moved to a new location as the zoo prepares for renovations. (Photo by Alan Diaz/AP Photo)

In this photograph taken on April 16, 2014, a veterinary staff member of the Sumatran Orangutan Conservation Programme center conducts medical examinations on a 14-year-old male orangutan found with air gun metal pellets embedded in his body in Sibolangit district in northern Sumatra island. (Photo by Sutanta Aditya/AFP Photo)

A photo made available 18 April 2014 shows Spix Macaw chicks “Karla” (L) of 26 grams and brother “Tiago” (R) of 70 grams being attended by a keeper at the Association for the Conservation of Threatened Parrots (ACTP), in Schoeneiche, Germany, on 17 April 2014. Two Spix Macaw (Cyanopsitta Spixii) parrots, which are already extinct in the wild, hatched at the ACTP in the past few days. (Photo by Patrick Pleul/EPA)

AmBam, the largest and most famous western lowland gorilla at Port Lympne Wild Animal Park, UK, has been celebrating his 24th birthday, on April 15, 2014. Ambam became famous when his “gorilla walks like a man” videos went viral in 2011 with more than 5.9 million hits. The gorilla, who weighs in at 220 kg, has the ability to stand fully erect, which is uncommon among his species. (Photo by London News Pictures/Rex Features/SIPA Press)

Spectacled bear mother Cashu walks next to her cubs at the zoo in Frankfurt Main, Germany, 17 April 2014. Two bear cubs have taken their first excursion out into the fresh air. (Photo by Boris Roessler/AFP Photo/DPA)

A Gelada baboon is pictured at the zoo of the French eastern city of Amneville, on April 11, 2014. (Photo by Jean-Christophe Verhaegen/AFP Photo)

In this Thursday, April 13, 2014 photo, Harvey is weighted, after being bottle fed, to monitor his progress at the Best Friends Animal Society kitten nursery in the Mission Hills area of Los Angeles. Tens of thousands of people who think they are saving abandoned wild kittens by taking them to shelters are hastening their deaths because most shelters don't have round-the-clock staffs to care for them. (Photo by Damian Dovarganes/AP Photo)

A sun bear lies in its enclosure of the Zoologischer Garten zoo on April 17, 2014 in Berlin. (Photo by Johannes Eisele/AFP Photo)

Sri Lankan mahouts perform rituals on elephants to mark the Sinhalese and Tamil traditional New Year at an elephant orphanage in Pinnawala, about 45 kilometers (28 miles) northeast of Colombo, Sri Lanka, Wednesday, April 16, 2014. The orphanage is home to 83 elephants and a major tourist attraction in Sri Lanka. (Photo by Eranga Jayawardena/AP Photo)

This photo provided by the San Diego Zoo, shows an eight-and-a-half-month-old koala joey named Burra resting on his mother, Tonaleah, while the two received their weekly weight check by keepers at the San Diego Zoo. Animal care staff confirmed that Burra (whose name means big fella in the Aboriginal language) is right on track with his weight and that he is growing and developing as expected. Burra weighed 2.49 pounds while Tonahleah was a healthy 11.5 pounds. (Photo by Ken Bohn/AP Photo/San Diego Zoo)

Two cows fight during the “Combats de Reines” (Battle of the Queens), a traditional cow fight in Bussy-Chardonney, western Switzerland, 13 April 2014. During the combat the cows push forehead against forehead. The annual event exists since the 1920s. (Photo by Jean-Christophe Bott/EPA)

Grumpy Cat attends the 2014 MTV Movie Awards at Nokia Theatre L.A. Live on April 13, 2014 in Los Angeles, California. (Photo by Jason Merritt/Getty Images for MTV)

This picture taken on April 14, 2014 shows a giant panda playing in its enclosure at Hangzhou Zoo in Hangzhou, in eastern China's Zhejiang province. Giant pandas, notorious for their low s*x drive, are among the world's most endangered animals. Fewer than 1,600 pandas remain in the wild, mainly in China's Sichuan province, with a further 300 in captivity around the world. (Photo by AFP Photo)

A gaucho rides a wild horse during the annual celebration of Criolla Week in Montevideo April 16, 2014. Throughout Easter Week, “gauchos”, the Latin American equivalent of the North American cowboy, from all over Uruguay and neighboring Argentina and Brazil will visit Montevideo to participate in Criolla Week to win the best rider award. The competition is held from April 13 to April 20 this year. (Photo by Andres Stapff/Reuters)