Following the deaths of several endangered animals, wildlife activists are calling the Surabaya Zoo in Indonesia the "Zoo of Death" and are demanding a complete change in the zoo's management.

According to activists, many of the more than 2,200 animals in the zoo are all crammed in cages too small for their sizes and are not being fed well.

One of the most controversial incidents at the zoo was the death of a rare Sumatran tiger that died last April.

According to Petrus Riski of the Indonesian Wildlife Communication Forum, steps to control the overpopulation of animals should be put in action. "It can be done by sending them to other conservation facilities," he said.

Zoo keepers claimed that most of the deaths are due to natural causes, and said that the tiger's death was still unexplained. However, activists are keen to put the zoo on spotlight, referring to a string of unusual deaths in the zoo.

One of these incidents was the 18 month-old African lion that was found dead hanging in its cage in 2014. A giraffe was also found dead with about 18kg of plastic in its stomach, which are suspected to be thrown into the cage by zoo visitors. About 45 Komodo dragons, which are large lizard species found only in eastern Indonesia, died while fighting each other in overcrowded cages.

The zoo director said "bureaucratic hurdles" are keeping them from improving the zoo's conditions.

"We've been trying to resolve these issues one by one," said Director Aschta Boestani Tajudin. "I hope in three to four months from now we can finally solve the problem."

Just recently, an endangered Sumatran elephant named Yani died in Bandung Zoo in the city of Bandung in Java Island. The zoo is said to be just one of the many ill-maintained zoos in Indonesia.