Bihar will take the first step to set up a rhino-breeding centre on World Rhino Day, September 22.

The breeding centre will be on the premises of Sanjay Gandhi Biological Park, better known as Patna zoo.

'We have earmarked 5.5 acres on the zoo premises for the breeding centre,' said a senior environment and forest department official who is closely associated with the project. 'The foundation stone of the new facility will be laid on September 22 and it will be developed over the next one year.'

The Centre has provided Rs 3.62 crore for the project, approved by the central zoo authority.

The official said the existing enclosure for rhinos in the Patna zoo, which is spread over an area of around half an acre, had become congested owing to the growing number of rhinos which have been successfully bred at Patna zoo over 38 years.

'Rhinos need space and a lot of movement for better chances of natural breeding,' the official said. 'Our existing enclosure is capable of accommodating six rhinos comfortably but their number has now gone up to a dozen hence the new facility would provide a more conducive environment for the one-horned animals.'

A pair (male-female) of rhinos was first brought to Patna zoo from Assam in 1979. In 1982, a rescued rhino from West Champaran was brought to Patna. Since then rhinos their number has gone up to 12, which include six females. The latest addition was in July this year when two rhino calves were born in the zoo.

'Thanks to the natural breeding, we now boast of 12 rhinos - the highest number of one-horned rhinos in any zoo in the world, beating the San Diego zoo in US, which is home to 11 rhinos,' said the official.

A Patna zoo official said rhinos live in grasslands near rivers. 'We will develop marshy patches in the breeding centre and similar kinds of vegetation in the new facility so that rhinos could easily settle there and breed as they do in their natural habitat,' the official added.

There is always a high demand for rhinos in zoos across the world and hence having many rhinos would give Patna zoo leverage for animal-exchange programmes.

Patna zoo has provided rhinos to Delhi, Kanpur, Ranchi and Hyderabad zoos and also sent one rhino to a zoo in the US.