For eight years panda Cheng Gong has been a docile but popular feature at a special reserve in Sichuan province's capital.
But staff at the Chengdu Giant Panda Breeding Research Base suspect he may been growing a bit grumpy as he reaches middle age after finding a wild cat bitten to death on his playground.
The body was discovered on Sunday but keepers said there was no evidence the panda, one of 82 living on the base, had eaten any of the animal.
Yang Cheng, who studied wildlife conservation at Sichuan Agricultural University, has worked at the base for three years. He said: "Pandas both in the wild and in captivity have a strong sense of territory and would take any means possible to safeguard it.
"The wild cat has intruded into Cheng Gong's playground and has been killed by it."
It is the first time a wild cat has been bitten to death since the base opened in 1987, said its director Zhang Zhihe, but there had been reports of the bears biting goats in the wild in Nanbu and Pingwu counties in Sichuan.
Cheng Gong, whose name translates literally as "success", has a twin sister and is bold and agile, said Yang. His mother Cheng Cheng, now 24, which is the equivalent of 70 human years, was one of the first pandas bred on the base.
The 106-hectare Giant Panda Breeding Research Base in Chengdu is home to 108 species of animals and birds.
Source: China Daily