A polar bear believed to be the last in Africa has died at a South African zoo, a few months after his long-time mate passed away.

"Africa's last polar bear Wang had to be put down due to liver and heart failure," Johannesburg Zoo said in a statement on Wednesday.

The bear, said to be 28-years-old, came to Johannesburg in 1986, as part of a conservation exchange program with a zoo in Japan.

In 2010, Wang was diagnosed with liver ailments.

Jenny Moodley, spokesperson at the Johannesburg Zoo, told Al Jazeera that it was decided that the zoo would not replace Wang because of the climatic considerations. Polar bears are more suited to colder climates whereas Johannesburg's temperatures often reach in excess of 30 degrees Celsius.

"It was a decision taken in consideration of the climate. Polar bears adapt, but we are now looking to focus on the protection of indigenous animals.

"Wang was one of the highlights at the zoo. His condition over the past few days forced us to take the decision," Moodley said. 

Wang in the recent months was pining the loss of his partner of 27 years GeeBee, the zoo said.

GeeBee died of natural causes on January 12.

"In the recent weeks, his days were filled with enrichment programmes and special treats, including his own Valentine's Day celebration," the zoo said.

Source: Al Jazeera and agencies