
A Sumatran tiger cub stares at Melbourne Zoo in Melbourne, Australia, on 09 February 2011. The zoo is marking the first birthday of two Sumatran tiger cubs which are part of the zoo's endangered species breeding program. EPA/JULIAN SMITH

A Sumatran tiger cub roars at Melbourne Zoo in Melbourne, Australia, on 09 February 2011. The zoo is marking the first birthday of two Sumatran tiger cubs which are part of the zoo's endangered species breeding program. EPA/JULIAN SMITH

A Sumatran tiger cub plays at Melbourne Zoo in Melbourne, Australia, on 09 February 2011. The zoo is marking the first birthday of two Sumatran tiger cubs which are part of the zoo's endangered species breeding program. EPA/JULIAN SMITH

A Sumatran tiger cub plays at Melbourne Zoo in Melbourne, Australia, on 09 February 2011. The zoo is marking the first birthday of two Sumatran tiger cubs which are part of the zoo's endangered species breeding program. EPA/JULIAN SMITH