The giraffe baby stands in front of her mother “Dhakija” at the zoo in Erfurt, Germany, Monday, April 27, 2015. The baby was born on March 25, 2015. (Photo by Jens Meyer/AP Photo)

Film dog Tom Tom plays with a camera at a presentation for the dog and cat show in Dortmund, Germany, Tuesday, April 28, 2015. The eight year old Tibetan terrier played in several TV shows and commercials and shows his talents at the fair in Dortmund. (Photo by Martin Meissner/AP Photo)

Film dog Jo Jo performs on a skateboard at a presentation for the dog and cat show in Dortmund, Germany, Tuesday, April 28, 2015. (Photo by Martin Meissner/AP Photo)

Film dog Jo Jo performs on a skateboard at a presentation for the dog and cat show in Dortmund, Germany, Tuesday, April 28, 2015. (Photo by Martin Meissner/AP Photo)

Film dogs Tom Tom, right, and Jo Jo perform with shopping carts at a presentation for the dog and cat show in Dortmund, Germany, Tuesday, April 28, 2015. (Photo by Martin Meissner/AP Photo)

Film dog Jo Jo jumps on a skateboard at a presentation for the dog and cat show in Dortmund, Germany, Tuesday, April 28, 2015. (Photo by Martin Meissner/AP Photo)

Film dogs Tom Tom, left, and Jo Jo perform with a camera at a presentation for the dog and cat show in Dortmund, Germany, Tuesday, April 28, 2015. (Photo by Martin Meissner/AP Photo)

Gaya, a Devon Rex kitten, waits to be evaluated by a judge in Bucharest, Romania, Sunday, April 26, 2015. More than 250 cats entered the international feline beauty competition in the Romanian capital. (Photo by Vadim Ghirda/AP Photo)

In this photo taken Thursday, April 23, 2015, a sparrow hawk looks up after catching a pigeon on a falcon farm, near the northern Serbian town of Coka. Most of the birds end up in the Emirates which has a long tradition of falconry. The sport involves trained birds that typically circle above the falconers and take high-speed dives at flushed prey such as grouse. (Photo by Darko Vojinovic/AP Photo)

Steam rises from a horse as it gets a bath after a morning workout at Churchill Downs Tuesday, April 28, 2015, in Louisville, Ky. (Photo by Charlie Riedel/AP Photo)

Lazio's mascot eagle Olimpia is attacked by a crow as it flies before the start of their Serie A soccer match against Chievo Verona at the Olympic stadium in Rome, Italy, April 26, 2015. (Photo by Max Rossi/Reuters)

Three-month-old baby bears play at a wild animal park in Kunming, Yunnan province, China, April 27, 2015. (Photo by Wong Campion/Reuters)

A woman holds a black-tufted marmoset (Callithrix penicillata) monkey, known as “Mico-estrela” in Portuguese, after it was fed milk at the Jaragua park in Sao Paulo April 27, 2015. (Photo by Nacho Doce/Reuters)

Yunona, a three-year-old female Amur tiger, lies inside an open-air cage at the Royev Ruchey Zoo on the suburbs of the Siberian city of Krasnoyarsk, Russia, April 28, 2015. (Photo by Ilya Naymushin/Reuters)

Pamir, an eight-year-old Tien Shan White Claw bear, reacts inside an open-air cage at the Royev Ruchey Zoo on the suburbs of the Siberian city of Krasnoyarsk, Russia, April 28, 2015. (Photo by Ilya Naymushin/Reuters)

Arnaldo, a three-year-old male North American cougar or puma, yawns at the Royev Ruchey Zoo on the suburbs of the Siberian city of Krasnoyarsk, Russia, April 28, 2015. (Photo by Ilya Naymushin/Reuters)

Almaz, a five-year-old male white African lion, lies inside an open-air cage at the Royev Ruchey Zoo on the suburbs of the Siberian city of Krasnoyarsk, Russia, April 28, 2015. (Photo by Ilya Naymushin/Reuters)

A picture made available on 22 April 2015 shows an Iguana in a zone of Guapiles, in the province of Limon, Costa Rica, 18 April 2015. (Photo by Jeffrey Arguedas/EPA)

Newborn white Bengal tigers, a male and female born on April 18, are being fed by their guardians at a private zoo in Borysew near Lodz, central Poland April 28, 2015. (Photo by Tomasz Stanczak/Reuters/Agencja Gazeta)

A newborn white Bengal tiger, born on April 18, sticks out its tongue while being fed by a guardian at a private zoo in Borysew near Lodz, central Poland April 28, 2015. (Photo by Tomasz Stanczak/Reuters/Agencja Gazeta)

A monkey crosses a road as motorists travel along it inside the Sanjay Gandhi National Park, in Mumbai, India, 22 April 2015. (Photo by Divyakant Solanki/EPA)

A handout photograph provided by Brian Kubicki of Costa Rican Amphibian Research Center on 26 April 2016 shows a “Crystal frog”, Hyalinobatrachium dianae (H. diane). This frog was discovered by US biologist Brian Kubicki and Costa Ricans Stanley Salazar and Robert Puschendorf in a rainy forest of Costa Rican caribbean after 40 years without notice of any new example of this kind. (Photo by Brian Kubicki/EPA/Costa Rican Amphibian Research Center)

A handout photograph provided by Brian Kubicki of Costa Rican Amphibian Research Center on 26 April 2016 shows a “Crystal frog”, Hyalinobatrachium dianae (H. diane). (Photo by Brian Kubicki/EPA/Costa Rican Amphibian Research Center)

Spectacled caimans (Caiman crocodilus) are seen at the Aurora zoo in Guatemala City on April 27, 2015. (Photo by Johan Ordonez/AFP Photo)

Giant panda “Yuanzai” enjoys an ice cube filled with its favorite treats at the Taipei Zoo in Taipei, southeast China's Taiwan, April 26, 2015. Taipei Zoo has been given the panda some special cooling treats due to the hot weather these days. (Photo by Xinhua/Sipa Press)

A Chimpanzee is sleeping at a zoo in Chengdu, Sichuan province, Southwest China 28th April 2015. (Photo by Yong Wang/ZUMAPress)

Animals at the zoo Hagenbeck in Hamburg, Germany, April 29th, 2015. (Photo by Action Press/ZUMAPress)

This photo provided by The Marine Mammal Center shows a stranded sea lion pup lying next to a car on a San Francisco street Thursday, April 30, 2015. Video from The Marine Mammal Center in nearby Sausalito shows the male sea lion nicknamed Rubbish hiding under a car and waddling away from rescuers. They eventually got a net around the pup, moved it into a crate and took it to the center. KNTV reports that a veterinarian there recognized Rubbish, who also was rescued in Santa Barbara in February. Then, he was treated for pneumonia and malnutrition. (Photo by Adam Ratner/The Marine Mammal Center via AP Photo)

Afghan hounds Golea's Varvara, left, and Zindehsjah's Farasha run during one of the competitions at the International Greyhound Race in Wismar, Germany, Sunday, April 26, 2015. Around 120 greyhounds run in various categories and classes at the meeting organized by the Greyhound Friends Society of Mecklenburg-West Pomerania. (Photo by Jens Buettner/AP Photo/DPA)

Afghan Hound Golea's Varvara takes part in a competition at the International Greyhound Race in Wismar, Germany, April 26, 2015. About 120 greyhounds participated in the various categories at the event organized by the Greyhound Friends Society of Mecklenburg-Western Pomerania. (Photo by Jens Buettner/EPA)

Barn Swallows (Hirundo rustica) birds are pictured on April 28, 2015 in Barhoeft, Germany. (Photo by Stefan Sauer/AFP Photo/DPA)

Chimney swallows (Latin name: Hirundo rustica) sit on a docking line of a vessel at the harbour of Barhoeft, Germany, 28 April 2015. (Photo by Stefan Sauer/EPA)

A Canada goose and a gosling feed near the Schuylkill River Friday, May 1, 2015, in Philadelphia. (Photo by Matt Rourke/AP Photo)