Researchers at Simon Fraser University have devised a fiendishly clever way to trick rats into getting inside a trap by exploiting their snacking preferences, the comfort of community, the promise of sexy fun time and even the cries of baby rodents to play on a mother’s instincts.
Animal communication expert Gerhard Gries started by creating a food odorant that mimics a smorgasbord of cheese, hazelnuts, chocolate, fresh meat and other rat favourites.
That was effective — certainly better than commercially available attractants — but rats are naturally wary of new objects and even the promise of a tasty meal isn’t always enough to lure them in.
So Gries added pheromones and steroids, such as male testosterone or female progesterone and estradiol to let the rats know that, A) there is another rat inside, so it’s not that dangerous and, B) maybe you’ll get lucky if you go inside. The female blend increased captures of male mice eight-fold and male rats 13-fold, while synthetic testosterone increased captures of adult female mice 15-fold.
“We were pleasantly surprised, it’s an amazing increase in bait attractiveness,” said Gries, who is developing systems effective on Norway rats and house mice. Those results were published in the journal ChemBioChem.
