Vancouver's rat population appears to be growing. There is no official rat tracker — but pest control professionals are reporting more rodent calls than ever before

It's created a serious need for a more effective method of capturing and killing the disease-carrying pests, which is what SFU biology professor Gerhard Gries has been working on for the past eight years.

He believes he's developed a bait system that can be up to 20 times more effective than poison-based traps, and he's confident it could have a significant impact on Vancouver's rat population.

"It could really help alleviate the rat problem in Vancouver, and not just in Vancouver but all over the place," said Gries.

Multipronged approach

His system includes several components, including a food element that Gries said contains odours of all the different kinds of foods rats are known to like.

"So no matter what the rat is craving on that particular day, let's say it really would like to have a bit of cheese, the cheese odour is in our bait," Gries said.

The bait also has a synthetic replica of the sex attractant pheromones found in mouse and rat urine. Gries said the compound was developed in his lab, and including it in the bait has proven to be highly effective.

"With the sex attractant message, you will capture anywhere between 10 to 15 times more rats, so it's really very, very potent."

But Gries said rats have neophobia, or a fear of new things, so despite the smells of food and a potential mate, they can still be hesitant to enter a trap.

This prompted Gries to develop the final component of his bait technology — an electronic gadget that emits a sound similar to that of baby rodents.

He said, "That tells the rat now, 'OK, it smells like food, it smells like rat, it sounds like rat so it's probably safe to enter that trap box.'"

Gries said by adding the sound element, the efficacy of the bait increased by another four or five fold. 

International interest

Gries said he has recently had calls from companies in Europe that are interested in his technology, which will likely be a bit more costly than more widely used solutions, like poison stations.

But he believes his bait will not only be more effective than poison, it will also be better for the environment.

He explained that rats often eat the poison in a conventional trap but are not killed. This then makes them vulnerable to predators, which can get secondary poisoning by eating the rats.

"So they will be killed or badly injured as a result of that feeding — and their offspring for that matter. So the poison really enters the entire foodchain."

Pets can also be killed by rat poison.

Building a better rat trap

Gerhard Gries said he and his team will be working with an industry sponsor to develop an effective trap to go along with their bait technology.

They hope to use a trap that is capable of multiple killings, and that drops the rat outside of the trap for a predator to pick up, therefore requiring little servicing.

Gries is hoping to get the product to market sometime in the new year.