left the zoo after three months to return to animal collecting. After several other equally short-lived zoo directors, Wegeforth appointed the zoo's bookkeeper, Belle Benchley, to the position of executive secretary, in effect zoo director; she was given the actual title of zoo director a few years later. She served as zoo director from 1925 until 1953. For most of that time she was the only female zoo director in the world. She was succeeded as director by Dr. Charles Schroeder. The San Diego Zoo was a pioneer in building "cageless" exhibits. Wegeforth was determined to create moated exhibits from the start, and the first lion area at the San Diego Zoo without enclosing wires opened in 1922. Until the 1960s, admission for children under 16 was free, regardless of whether they were accompanied by a paying adult. The zoo's Center for Reproduction of Endangered Species (CRES) was founded in 1975 at the urging of Kurt Benirschke, who became its first director. CRES was renamed the division of Conservation and Research for Endangered Species in 2005 to better reflect its mission. In 2009, CRES was significantly expanded to become the Institute for Conservation Research. The world's only albino koala in a zoological facility was born September 1, 1997, at the San Diego Zoo and was named Onya-Birri, which means "ghost boy" in an Australian Aboriginal language. The San Diego Zoo has the largest number of koalas outside of Australia. In 2014, a colony of African penguins arrived for the first time in the zoo since 1979. They have since moved into Africa Rocks when it opened in 2017. In 2016, Baba, the last pangolin on display in North America at the time, died at the zoo. In October 2020, two gorillas charged at the glass of their enclosure, damaging the outer pane. Escapes The San Diego Zoo has had a number of notable escapees through the years; the most noteworthy of them is Ken Allen, a Bornean orangutan who came to be known as "the hairy Houdini", for his many escapes. In 1940, a Malayan Tapir managed to escape several times, earning it the nickname "Terrible Trudy". In 1977, an animal control officer for the County of San Diego, Tom Van Wagner, a previous employee of the San Diego Zoo as a tour bus guide, captured a Tasmanian devil escapee in a south central San Diego home's garage. The animal