Rajasthan govt sent tiger siblings to repopulate Sariska

DOOMED? Two sisters and their half-brother were selected without DNA test

Hindustan Times, 29 June, 2009

As the Rajasthan forest department celebrates the anniversary of India’s first wild tiger repopulation drive, evidence with Hindustan Times suggests that all three big cats – a male and two females -- airlifted from Ranthambhore to repopulate Sariska are siblings.

All three tigers come from the same father, known as Anantpura male. The two females are from the same mother, known as Jhalra female or machhli. Before selecting tigers for relocation, no DNA analysis was conducted to ensure genetic dissimilarity. As a result, if corrective actions are not initiated, the future tiger population at Sariska might suffer acute inbreeding depression (See box).

An analysis of the photographic census data gathered by Wildlife institute of India (WII) in 2006 clearly shows that one adult male occupied the entire territory where these three tigers were born during 2004-2006. Tigers are highly territorial and a male do not allow other males to breed with the females residing within his territory.

“While there are enough telling evidences to conclude that all tigers sent to Sariska came from the same father, there is nothing to suggest otherwise. The state authorities should have used the WII expertise of DNA analysis to eliminate the risk,” said Dr Dharmendra Khandal, a field biologist based in Ranthambhore.

It is very important to conduct DNA test before introducing tigers, particularly when we are repopulating from zero. In interconnected forests, a bigger breeding population keeps the gene pool healthy. But one has to be very careful about pocket reserves like Ranthambhore or Sariska,” said PK Sen, former director, Project Tiger.

While Rajasthan forest bosses denied that the male and female tigers came from the same father, PR Sinha, director of Dehradun-based Wildlife Institute of India, agreed that only a DNA analysis could confirm it. “We did not conduct any DNA test so far as it was not felt necessary. Having two sisters in Sariska is not an issue but the male must be from a different lineage for healthy reproduction. We have blood samples. We can check,” he said.

Dr Ullas Karanth, India’s leading tiger scientist, felt that gene analysis was a must for selecting tigers for relocation: “Why take chances when a DNA test can resolve such issues? These relocation drives seem like knee-jerk exercises done in a hurry but we cannot compromise on science.”

Experts, however, claim that the situation can still be salvaged. “Even if these tigers are siblings, they are only a part of the source population as we are supposed to bring in more tigers. If these new tigers are selected genetically, the future Sariska population won’t be affected,” explained Dr Qamar Qureshi, a scientist with Wildlife Institute of India.

Only if the Rajasthan forest department learns its lessons and opts for DNA tests before picking up another arbitrary male for Saiska to meet its self-imposed July 11 deadline. Ensuring genetic variation is one of the fundamental requirements in the protocol recently issued by the National Tiger Conservation Authority (NTCA) for tiger relocations.


INSIDE STORY

Decoding the Sariska tiger puzzle

All the three tigers sent to Sariska so far have grown up in and around the tourism zone of the Ranthambhore National Park. Many field guards, guides and regular tourists have spotted and photographed them. They all have a clear idea of their lineage and can confirm they are step-siblings.

“Not many will go on record fearing action against them by the park authorities,” said Aditya Singh, Ranthambore’s well-known wildlife photographer. “But we have seen these tigers grow up. The male was born to the tigress in the Chiroli zone of the park, and the two females to another tigress in the Jhalra zone. All three cubs were fathered by the same male as he was the only dominant tiger in that area since 2004. He has been filmed mating with the Jhalra tigress. I can’t believe the park authorities did not know this.”

Hindustan Times has analysed the Wildlife Institute of India’s 2006 tiger census. The census extensively used camera traps and clicked 356 photographs of 31 tigers in Ranthambhore over 19 days.

The result threw up five adult males – two of them too young to have fathered the male cub born to the Chiroli tigress. It clearly defined the territories of the three other males, as well as that of the Jhalra and Chiroli females.


As the accompany map of Ranthambore shows, the territories of the Jhalra and Chiroli females fall within the territory of Anantpura male. Except under rare circumstances, the other males in the park could not have mated with either of the two females without dislodging the Anantpura male from this area. It follows that all cubs born to the Jhalra and Chiroli females during that time were fathered by Anantpura male.

“Very rarely will a male tiger allow other males in his territory,” said Fateh Singh Rathore, ex-conservator of Ranthambore. “I do not see any chance of any other male mating the Anantpura male’s tigresses.”

“The fact that the Anantpura male shared space with the Chiroli male cub indicates that they are father and son. A male tiger would kill the litter of another male,” said P.K. Sen, former director, Project Tiger.