Here's a couple of possible solutions from New Scientist:

The natural assassin

Question
Because there are environmental regulations covering the use of ant powder, is there any reason why you could not tame an anteater to do the job for you, therefore providing a wholly natural solution to the problem? Would a single suburban garden be enough to sustain the anteater or would you have to hire it out to neighbours and friends?
Brian Jackson , UK

Answer 1:
Anteaters have developed special features for feeding from anthills in South America. However, their enormous claws, said to be able to kill a jaguar, would not be suited to breaking open the patios and house bricks that house ant colonies in the British suburbs. Their long snouts would be equally useless for poking into cracks between bricks, because they have evolved into toothless tubes for sticking inside the huge mounds made by colonial insects in their native countries - not the small holes made by pesky ants in UK gardens.

Finally, anteaters need to eat as many ants as possible while awake, because ants do not provide very nutritious fare. The average suburban garden in the UK simply would not have enough ants for an anteater to survive, even if it were shared with other households and their gardens.
Victoria Clent , Northampton, UK


I thought of this possibility a while back, but it seems it isn't a very good idea after all!



Answer 2:

The trouble with anteaters, and other creatures that eat ants, is that they actively hunt out ants or termites rather than just catching them as they wander past. This means that once your garden became ant-free, your anteater would be looking to move on.

The Australian thorny devil is one of the few animals that relies on the ants to do the legwork, but it is a bit impractical for our climate.

Instead, I invented a very good, environmentally friendly cure while I was living in Hong Kong. First, you need to find a wandering ant in your house, garage, garden or greenhouse and then pile a teaspoon of sugar in front of it. Wait a few hours, and you will see that a clearly visible line of ants will link the spoonful of sugar with their nest.

Once you have located this point, decide where you would like the ants to stop - just outside your house or garage, rather than inside, is as good a place as any. Pile another tablespoon of sugar at this point. The ants will pick this up, turn round and return to the nest with it, and will not bother travelling any further. The column of ants to the original teaspoon of sugar will quickly peter out, and you can clear it up.

Then keep an eye on the new pile of sugar - it may need topping up occasionally if you have a large nest, but it will certainly solve your problem.
Jason Miller , Hemel Hempstead, Hertfordshire, UK