A photograph purporting to be the first sighting of a South China tiger for more than 30 years has prompted a search for the endangered animal.

Forestry officials have set up checkpoints and banned hunting around a mountain where a farmer and former hunter snapped the animal gazing directly at the camera.

Experts are to travel to northwestern Shaanxi province to try to find traces of a tiger that has not been seen alive outside a zoo for 34 years.

The state-run media hailed the photograph as proof of the survival of an animal listed as among the ten most-endangered in the world.

But for some, the picture, taken on October 3 by Zhou Zhenglong with a digital camera, is too good to be true. Many people have questioned its veracity and suggested that digital technology may have been used to alter the image.

Forestry officials in Shaanxi have rushed to Mr Zhou’s defence. They said that he had shot 71 photographs, 40 with a digital camera and 31 on film, but it had been decided to release only one shot.

Zhu Julong, deputy head of the provincial department, said: “Zhou Zhenglong risked his life in taking these photos, so they are very precious. We are being cautious and responsible in releasing one of the photos.”

Some internet critics cited irregular effects of lighting and focus, saying that the colour of the tiger’s fur looked unreal and too shiny to be authentic.

Fu Dezhi, a botanist from the Chinese Academy of Sciences, voiced doubts about the vegetation in the photograph, saying that it would be unusual to find a leaf of a size similar to the one that obscured much of the tiger’s head. “I have never discussed whether this is a real tiger because that issue is not my specialty,” he wrote in a blog. “But based on my botanical expertise . . . this is just a ‘paper tiger’.”

Mr Zhou and provincial authorities travelled to Beijing last week for meetings at the state forestry administration.

Officials declined to comment on whether they had reached a decision on the authenticity of the photograph.

Mr Zhou told The Times: “I spent more than a month in the mountains to take these pictures. They are 100 per cent real. No matter who says they are fake, they cannot change the facts.” He said that he planned to set out again into the mountains. “I can’t promise to take more pictures, but there’s hope. The wild tigers are in the mountains.”

There were 4,000 South China tigers in the 1950s, but the population has declined rapidly. Zhenping county has been a home of the tiger, and local people have reported hearing roars and seeing traces in recent years. Provincial forestry officials organised a survey in 2006 but were unable to confirm claims by villagers of 17 tiger sightings. However, they reported finding footprints, hair and teeth of tigers during their search.

Huang Gongqing, a China expert, said that it did not matter whether the photographs were real or not. “If fewer than 100 of the species survive, it is basically impossible for them to reproduce. Its extinction is just a question of time.”

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