News

Lately, while walking down Orchard Road, one of our prized tourist destinations, I have been seeing rats running across the pavement. Apart from the poor impression this sight gives tourists, it seems to indicate a growing rat population in the city. Controlling access to edible garbage and food is one way to control the number of rats, which are prolific breeders. But this is not a reliable solution in a crowded city like ours, with ever-increasing amounts of garbage and food waste. Rats can also gnaw through almost anything to get to food stocks. Another way is to lay poisoned bait. The danger with this method is that other animals could consume the poisoned bait, and animals that feed on rats could also get killed. There is also a risk that children might come across the bait. There is a third approach we should be deploying in a significant way – making the rats infertile, thereby preventing population growth. One way is to use non-toxic chemical baits which make rats infertile after they eat them. Over time, this can greatly reduce the rat population. The other is to breed infertile male rats, and periodically release them into the city. This is similar to how the Aedes mosquito population is controlled. We need to focus research on these options to develop more effective strategies. Singapore, with one of the world’s highest-density populations, needs effective measures to prevent the kind of rat population growth seen in many other cities.