While you’ve probably heard the expression “I smell a rat,” it’s less likely you’ve wondered about whether a rat smells you. As it turns out, rats have pretty sharp sniffers.

rat's sense of smell

Learn about a rat’s sense of smell, then take a look at scents that may repel rats — or even attract them.

How Strong is a Rat’s Sense of Smell?

Rats rank pretty high in terms of olfactory abilities. In fact, Harvard research shows that rats are highly sensitive to smells, and some species have even been trained to detect odors specific to land mines and tuberculosis.

Are There Scents That Can Repel Rats?

There are some scents that repel rats, at least according to a study by Harvard Medical School. A team of neuroscientists found that rats would instinctually avoid a chemical compound called 2-phenylethlyamine that occurs naturally in the urine of carnivores. While it is possible to purchase a variety of carnivore urine online, chances are that most people would want to avoid having a home highly saturated in fox urine. 

To humans, 2-phenylethlyamine is mildly annoying. However, trimethylamine, a related compound, is downright offensive to people. In fact, it’s the chemical culprit that is the signature component in rotting fish.

What Scents Attract Rats?

It should go without saying that the smell of food sources will attract rats. However, scientists from Simon Fraser University have found yet another scent that is attractive to rats, or the females at least. They’ve developed a new way to exterminate by the sex pheromone of the male rat.

According to the scientists, female rats will be drawn to the scent of a potential mate. What they find when they follow their noses, however, is a trap rather than a romantic tryst. And when the number of females in a colony declines, reproduction numbers dip, which means rat populations decrease in size.

What Attracts Rats to Your Home Other than Smells?

With such outstanding olfactory senses, it’s a no brainer that food items can attract rats to your home. That’s why it’s important to keep a tidy house, vacuuming crumbs, cleaning grease spills and wiping countertops (even under toasters and toaster ovens). Additionally, you should keep food, like nuts, cereal and bread and even pet food stored in tightly sealed plastic or metal containers. And don’t leave pet food out at night, if possible.

Here are some other ways you can try to make your home less appealing to rats:

  1. Keep firewood, bricks or debris as far from your home as possible. These can attract rats as they look like great places to call home.
  2. Seal holes or cracks that are larger than 0.25 inches in diameter to help keep rats from entering your home. Additionally, install weather stripping on the bottom of doors to block these entry points.
  3. Keep tree branches, vines and vegetation trimmed away from your home to help eliminate easy access to your foundation or rooftop.
  4. Remove food wrappers and other food related trash from the yard
  5. Keep trash cans secured to reduce the food odor which can attract rats closer to your home