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
Zoo Tycoon 2: Endangered Species 3D. "Endangered Species" contains 20 brand new animals from various countries and habitats. The expansion focuses on endangered and critically endangered animals like the Orangutan, Javan rhinoceros, Florida panther, and Giant sable antelope. However, other animals are included that are 'lower risk' and 'vulnerable' as well. "Zoo Tycoon 2"'s first expansion, "Endangered Species" updates most of the animal behaviors; basic herding behaviors were added (more advanced herding and pack behavior came out in "") and animals cannot breed with their siblings, parents or grandparents. Animal models and skins are also slightly more realistic than the animals from the original game.