A macaque monkey catches knives as it works with a trainer at the Qilingang Monkey Farm on February 2, 2016, in Baowan village, Xinye County, Henan Province, China. The area boasts a centuries-long and lucrative history of raising and training monkeys for performance. In Xinye, villagers are seeing an increase in business with the lunar calendar's “Year of the Monkey.” Farmers say most of the monkeys are bred and raised for domestic zoos, circuses, and performing groups, but add that some are also sold for medical research in China and the United States. Despite the popularity of the tradition, critics contend the training methods and conditions constitute animal cruelty. #

An Amur leopard called Leo M31, on loan from the Prague Zoo as part of the Amur Leopard Breeding program, catches a rabbit in Primorye Safari Park, about 70 kilometers from Vladivostok, Russia, on February 7, 2016. #

Guilherme Trivellato, from the British biotec company Oxitec, releases genetically modified Aedes aegypti mosquitoes—a vector for the spread of the Zika virus—in Piracicaba, Brazil, on February 1, 2016. Oxitec raises male mosquitoes that have been modified to produce offspring that do not live. These males are released into the target area, where they compete with wild males to mate with the wild females. Brazil is in the midst of a Zika outbreak and authorities say they have also detected a spike in cases of microcephaly in newborn children, but the link between Zika and microcephaly is as yet unproven. #

Cathy Schlott, the curator for behavioral management and education for the National Aviary in Pittsburgh holds a three-month-old Linnaeus's two-toed sloth the Aviary acquired for education and interactive encounters during a news conference at the Allegheny County Airport after it arrived on a private jet on February 8, 2016, in West Mifflin, Pennsylvania. The animal is most closely related to anteaters and armadillos and is now 10 inches long and weighs about two pounds. Adults weigh between 15 and 20 pounds. #

A tiger tries to grab a live chicken offered by tourists inside a sightseeing vehicle at the wildlife world in the Locajoy Holiday Theme Park in Chongqing, China, on January 8, 2016. Tourists and predators have switched places at the zoo, where visitors are paying to be locked in a cage and stalked by big cats and bears. Chunks of fresh meat and live chicken are tied to the outside of a vehicle, which drives through the enclosure, in a bid to attract the predators and give tourists the closest possible dining experience with them, without becoming dinner themselves. #

Cajun Mardi Gras revelers chase a guinea hen during the Faquetaique Courir Mardi Gras chicken run on Fat Tuesday, February 9, 2016, in Chatangia, Louisiana. Revelers romp through the countryside causing mischief and begging then celebrate by dancing. #

An eight-month-old female California sea lion pup, found sleeping in a booth in the dining room of the iconic Marine Room restaurant in La Jolla, California, on February 4, 2016. A rescue team from the SeaWorld San Diego theme park was called in to pull the barking mammal from the booth and place it in a net. The mammal was then taken to SeaWorld for care, said David Koontz, a spokesman for the tourist center. #

Merrylu Casselly and Jozsef Richter, both circus performers, pose with an elephant as they celebrate their wedding in front of Budapest's basilica on Valentine's Day in Budapest, Hungary, on February 14, 2016. #

A long-eared owl (Asio otus) in a tree near Lebus, Germany, on January 22, 2016. Many long-eared owls spend the winter in the Oder region, sleeping in trees during the day and hunting at night. #

A photograph made available on February 8, 2016, shows a leopard attacking a forest official at a school in Bangalore, India, on February 7, 2016. The leopard strayed into an empty school, injuring three people before being captured in a 10-hour operation by local officials, police said. A conservationist and a wildlife official were mauled by the leopard, while a cameraman from a local television channel suffered injuries when he slipped while trying to get footage of the animal. #

A dog runs on the frozen surface of the Yenisei River in Taiga, with the air temperature at about minus 28 degrees Celsius (minus 18.4 degrees Fahrenheit), outside Krasnoyarsk, Siberia, Russia, on January 28, 2016. #

A captured monkey tries to untie his legs at a residential colony in Mumbai on February 5, 2016. The monkey was captured by a professional after complaints to the forest department by local residents and shop owners that the primate was causing a nuisance, including stealing food and damaging stocked items in shops. #

Young Pokot men restrain a bull as another prepares to shoot an arrow with a shallow point into its neck to extract blood, during an initiation ceremony in Baringo County, Kenya, on January 20, 2016. Far from the bustling city of Nairobi, in an isolated corner of Kenya's Rift Valley, young men from the Pokot community spear a bull in a ceremony called Sapana that takes them into adulthood. Following the ritual improves men's marriage prospects, provided they can amass a dowry of livestock for their bride. #

Mara, a 12-year-old hippopotamus, presses her snout against her enclosure at the Los Angeles Zoo on February 12, 2016. “Hippo Encounter” is a new hands-on opportunity for visitors to see behind the scenes at the hippo enclosure at the zoo. Keepers introduce guests to both Mara and her 15-month-old baby Rosie, and share specifics about their daily routines, care and training. #

Russia's Arctic mechanized infantry unit holds military drills to learn how to ride a reindeer sled at the reindeer farm near the Lovozero settlement in Russia’s Murmansk Oblast. #

An eagle is seen gliding straight toward a drone before clutching it and dragging it to the ground in Rotterdam, Netherlands, on January 29, 2016. Dutch police puzzling over how to remove drones that pose a public safety threat are testing a way to get the job done in one fell swoop: with trained eagles. #

A heat-stressed koala waits as a resident pours water on its back on December 19, 2015 in Adelaide, Australia. Adelaide was experiencing an extreme heatwave, with temperatures reaching over 40 degrees Celsius for five consecutive days. #

Aye Aye Maw, owner of the shelter, working among cats on the outskirts of Yangon, Burma, on February 4, 2016. The shelter houses over 200 animals and provides food and basic medical treatment for the animals, which the owners say were rescued from Yangon streets. #

Seven-year-old Hungarian herding dog Derci runs on Olympiaberg Hill in Munich, Germany, on January 4, 2016. The breed, also known as Puli, has an inherently thick and shaggy coat. #