In this December 16, 2011 file photo, a cluster of little brown bats hibernate in New Mammoth Cave near LaFollette, Tenn. A fungal disease that has killed millions of bats has been confirmed in Washington state, the first time white-nose syndrome has turned up in the western United States, federal wildlife officials said Thursday, March 31, 2016. Testing by the U.S. Geological Survey's National Wildlife Health Center verified the disease in a little brown bat found in North Bend, about 30 miles east of Seattle. (Photo by Amy Smotherman Burgess/Knoxville News Sentinel via AP Photo)





A monkey walks on main power lines on a main road in Colombo, Sri Lanka March 29, 2016. (Photo by Dinuka Liyanawatte/Reuters)





Felix, a nine-year-old polar bear, jumps into a pool inside its enclosure at the Royev Ruchey Zoo in Krasnoyarsk, Siberia, Russia, March 29, 2016. (Photo by Ilya Naymushin/Reuters)





A couple of polar bears, Felix (L), a nine-year-old, and Aurora, a six-year-old, is seen inside its enclosure at the Royev Ruchey Zoo in Krasnoyarsk, Siberia, Russia, March 29, 2016. (Photo by Ilya Naymushin/Reuters)





Felix, a nine-year-old polar bear, shakes off water in a pool inside its enclosure at the Royev Ruchey Zoo in Krasnoyarsk, Siberia, Russia, March 29, 2016. (Photo by Ilya Naymushin/Reuters)





Three Asian lion cubs, born on January 25, 2016, stand next to their mother Lorena while being presented to the public at the Planckendael Park in Mechelen, Belgium March 30, 2016. (Photo by Yves Herman/Reuters)





An Asian lion cubs, born on January 25, 2016, walks next to his mother Lorena while being presented to the public at the Planckendael Park in Mechelen, Belgium March 30, 2016. (Photo by Yves Herman/Reuters)





Two Asian lion cubs, born on January 25, 2016, stay next to their mother Lorena while being presented to the public at the Planckendael Park in Mechelen, Belgium March 30, 2016. (Photo by Yves Herman/Reuters)





Qabid, a three-month old Indian rhinoceros, is seen next to his mother Karamat at the Planckendael Park in Mechelen, Belgium March 30, 2016. (Photo by Yves Herman/Reuters)





Qabid, a three-month old Indian rhinoceros, stays next to his mother Karamat at the Planckendael Park in Mechelen, Belgium March 30, 2016. (Photo by Yves Herman/Reuters)





Seagulls are seen in the old city of Nice, France, March 30, 2016. (Photo by Eric Gaillard/Reuters)





An endangered Amur leopard, which was euthanized on Tuesday due to kidney disease and old age, is seen at the Oregon Zoo in an undated handout photo provided by the zoo. (Photo by Michael Durham/Reuters/Oregon Zoo)





One of two rescued endangered olive ridley turtles arrives at Sea World's animal rescue center after being flown from the Oregon coast by the U.S. Coast Guard to San Diego, California March 30, 2016. (Photo by Mike Blake/Reuters)





One of two rescued endangered olive ridley turtles arrives at Sea World's animal rescue center after being flown from the Oregon coast by the U.S. Coast Guard to San Diego, California March 30, 2016. (Photo by Mike Blake/Reuters)





One of two rescued endangered olive ridley turtles swims in its new pool as it arrives at Sea World's animal rescue center after being flown from the Oregon coast by the U.S. Coast Guard to San Diego, California March 30, 2016. (Photo by Mike Blake/Reuters)





A gorilla named Susie sits in her enclosure at the Columbus Zoo and Aquarium in Powell, Ohio in this August 24, 2015 handout photo provided by the Columbus Zoo on March 16, 2016. Susie is helping provide fresh insight into the genetic differences between people and these endangered apes that are among our closest living relatives. (Photo by Amanda Carberry/Reuters/Columbus Zoo and Aquarium)





A gorilla named Susie eats a pumpkin in her enclosure at the Columbus Zoo and Aquarium in Powell, Ohio in this October 25, 2014 handout photo provided by the Columbus Zoo on March 31, 2016. (Photo by Amanda Carberry/Reuters/Columbus Zoo and Aquarium)





A Lemur catta, also known as ring-tailed lemur, with eleven-day-old cubs clinging to its neck and belly, walks along a tree at the Schoenbrunn zoo in Vienna, Austria, April 1, 2016. (Photo by Heinz-Peter Bader/Reuters)





A Lemur catta, also known as ring-tailed lemur, with eleven-day-old cubs clinging to its back, sits on a tree at the Schoenbrunn zoo in Vienna, Austria, April 1, 2016. (Photo by Heinz-Peter Bader/Reuters)





A Lemur catta, also known as ring-tailed lemur, with eleven-day-old cubs clinging to its back, walks along a tree at the Schoenbrunn zoo in Vienna, Austria, April 1, 2016. (Photo by Heinz-Peter Bader/Reuters)





A Lemur catta, also known as ring-tailed lemur, with a thirteen-day-old cub clinging to its back, sits on a tree at the Schoenbrunn zoo in Vienna, Austria, April 1, 2016. (Photo by Heinz-Peter Bader/Reuters)





One of the two Red Pandas (Ailurus fulgens) explores his surrounding during the opening of the new panda enclosure at Amersfoort Zoo, to where the two brothers moved in, im Amersfoort, The Netherlands, 01 April 2016. (Photo by Koen van Weel/EPA)





One of the two Red Pandas (Ailurus fulgens) nibbles on leaves during the opening of the new panda enclosure at Amersfoort Zoo, to where the two brothers moved in, im Amersfoort, The Netherlands, 01 April 2016. (Photo by Koen van Weel/EPA)





Female Siberian tiger Dasha yawns in the new enclosure at the zoo in Duisburg, Germany, 30 March 2016. The new facility is three times larger than the old one and will be opened to the public on the same day. (Photo by Roland Weihrauch/EPA)





This Monday, March 28, 2016 photo provided by the Santa Barbara Zoo shows a newborn baby giraffe and its mother, Audrey, in Santa Barbara, Calif. The unnamed Masai giraffe was born Saturday, March 26. (Photo by Santa Barbara Zoo/www.sbzoo.org via AP Photo)





Northern White-cheeked Gibbon, Nomascus leucogenys leucogenys, female with its baby (left) are pictured in their enclosure in Pilsen zoo, Czech Republic, March 31, 2016. (Photo by Pavel Nemecek/CTK via ZUMA Press)





Dolphins swim in a water tank as curtain of lights penerate at Otaru Aquarium in Hokkaido on March 29, 2016. The scene is observed in spring and fall season. (Photo by The Yomiuri Shimbun via AP Images)





A visitor presses against exhibit glass as Berit the polar bear while the animal swims laps around its enclosure at the Cincinnati Zoo and Botanical Garden, Friday, April 1, 2016, in Cincinnati. (Photo by John Minchillo/AP Photo)





A keeper with a red-necked wallaby cub in Lodz, Poland, 29 March 2015. The wallaby named Tosia was born at a private mini-zoo about four months ago and weighs only 500 grams. Tosia's mother died about 3 weeks ago and now she is bottle-fed every 3 hours and carried in a special bag by the employee. (Photo by Grzegorz Michalowski/EPA)





A keeper with a red-necked wallaby cub in Lodz, Poland, 29 March 2015. (Photo by Grzegorz Michalowski/EPA)