Surabaya Zoo performed on the animals found plastic and wood inside the animals. The death of Melani the tiger, one of only a few hundred Sumatran tigers left in the world, outraged animal activists when it was discovered that the tiger was suffering from extreme digestive disorders before being rescued from the zoo. On 28 January 2014 Surabaya Zoo authority announced that the zoo has a collection of 3,459 animals from 197 species, but 81 animals are sick, disabled, and old, and 44 of which are in severe conditions. An online petition that calls for the closure of Surabaya Zoo due to
Beijing Zoo collection. Leading Chinese universities also established a research presence in the zoo to study animal behavior and to breed endangered species. The zoo's development came to an abrupt halt during the Cultural Revolution as zoo staff were purged, research work stopped, and contacts with foreign zoos were severed. In the 1970s, as China forged diplomatic relations with the Western bloc, the zoo received animal gifts from the Australia, France, Mexico, Nepal, Spain, Sri Lanka, the United Kingdom, and the United States. The zoo also organized a four-year mission to Ethiopia, Kenya, and Tanzania, which brought back 157 species and 1,000