Bangladesh has joined the global battle to save Royal Bengal tigers, as the big cats continue to face threats to their survival.

The country's newly created Wildlife Crime Control Unit, equipped with modern weapons and high speed boats procured with the help of a $36 million loan from the World Bank, will go deep into the tigers' habitat to track threats from poachers.

An estimated 300 to 500 Royal Bengal tigers roam the sprawling, 6,000-square-kilometer mangrove forest in the Sunderbans area in the huge delta on the Bay of Bengal.

Authorities hope that the 300-member strong force will be able to deter wildlife smugglers. But depleting food reserves pose another huge challenge to the big cats.

The head of the Wildlife Trust of Bangladesh, Anwarul Islam, said deer and other prey which tigers depend on are being hunted down by villagers and this forces tigers to leave the forest in search for food. It is estimated that three are killed every year when they clash with villagers.

Wildlife officials are calling for stiffer penalties and longer jail term for people who kill tigers. They also hope that a tough new law will be drafted that will help curb poaching of an animal worth millions of dollars when it is killed.

The Sunderbans forest straddles India and Bangladesh and is among the most densely populated tiger habitats in the world. Conservationists say Bangladesh is critical to the fate of the tiger, whose numbers worldwide have plummeted to about 3,200.