Spotted deer at Alipore zoo. A Telegraph picture

Sixty spotted deer from Alipore zoo will be released in the Sunderbans so that they have more space and the Bengal tigers more food.

The zoo houses 70 spotted deer in three enclosures. Space is at a premium because the animals breed fast. Earlier, the animals with white spots on a reddish fawn coat used to be released in deer parks across the state when the zoo would run out of space.

Now, the authorities have decided to release them in the Sunderbans, thus improving the food supply of Bengal tigers that have been straying into villages and attacking people.

The deer bred in captivity will, however, not be transferred to tiger territory directly. “They would first be kept for some time in an isolation centre near the Sunderbans. Then the animals would undergo a health check-up. If they are found to be fit, they would be released in the wild,” said the principal chief conservator of forests, Atanu Raha.

The deer might not only face problems in adapting to a new and more hostile environment but also contract infections if they are released suddenly in the jungle, said an official.

The spotted deer, also known as the chital, is the most commonly found deer species in India. Their antlers, which they shed annually, are usually three-pronged and may extend to 2.5ft.

They are kept in three enclosures at Alipore zoo — the 100m x 50m main one and two 50m x 40m ones. Fights frequently break out in the main enclosure, after which groups of deer are isolated in the smaller enclosures.

Forest officials said releasing the deer from the zoo in the wild would “infuse new material into the spotted deer’s genetic pool”.

“A variety in the gene pool always helps. In 2003-04, some red pandas were released in the wild from Darjeeling zoo for the same reason. The deer will bring about diversity and add to the food supply of the tigers,” said a senior official of the state forest department.

Animal activists had complained about space crunch in the 45-acre zoo in the heart of Calcutta. Following an assessment, the Central Zoo Authority had ordered that three elephants — Mumtaz, Uttara and Phulwanti — be shifted from the Alipore premises.

“There are problems in shifting the elephants to north Bengal during the monsoon. They will be moved after the rainy season,” said zoo director Raju Das. “But the deer would be shifted within a few weeks.”