Auckland Zoo is a 16.35-hectare (40-acre) zoological garden in Auckland, New Zealand, situated next to Western Springs park not far from Auckland's central business district. It is run by the Auckland City Council with the Auckland Zoological Society as a supporting organisation. Auckland Zoo opened in 1922 experiencing early difficulties mainly due to animal health issues. By 1930 a sizeable collection of animals had been assembled and a zoological society formed. The zoo consolidated during the Second World War and was at that time under the leadership of Lt. Col. Sawer. After the war the collection was expanded, and in the 1950s chimpanzees were acquired to provide tea parties for the public's entertainment, but this practice ceased in 1964. In 1973 the zoo expanded into the adjacent Western Springs park. From the late 1980s to the present day, many old exhibits were phased out and replaced by modern enclosures. The zoo is separated loosely into areas divided by either the region of origin of the species exhibited, taxonically, or by biome. The zoo plays a part in conservation (mainly of New Zealand species), research and education. It has many modern features such as the New Zealand Centre for Conservation Medicine (NZCCM), and by the end of 2011 plans to open its largest development, Te Wao Nui, which will exhibit native New Zealand flora and fauna. Auckland Zoo is a full institutional member of the Zoo and Aquarium Association (ZAA), and received ISO 14001 accreditation for its Environmental Management System in 2007.