Whilst in theory a pair of rats could produce nearly half a billion descendants in just three years, in reality, this would never happen.
It is true that a rodent infestation can spiral out of control if ignored. However, there are far too many factors like the scarcity of food and shelter, disease, natural predation, in-fighting and ,of course, pest control, which mean the population will always be restricted (to a point).
The numbers are quite hard to get your head around, so Rentokil has created an interactive map, named ‘The Rise of The Rats’, to visualise this rapid reproduction rate.
The rapid rate of reproduction amongst rats might come as a shock to most people. It is precisely for this reason however, that pest control experts have always recommended the importance of prevention and recognising the early signs of a rat problem.
Stories about rising rat populations or ‘rat explosions’ in cities is nothing new. News about increasing sightings of rats often make the headlines in local newspapers, like the story from Halifax in Canada about the growing rat problem or a rodent population explosion in Ireland due to unusual winter weather conditions.
Weather and favourable environmental conditions can often be blamed for rising rat populations. However, rodents don’t need any extra help from mother nature to increase their numbers — humans can help them just as much.
The Rise of The Rats
‘The Rise of The Rats’ explains the breeding cycle of a brown rat living in an ideal environment.
- A female rat typically births six litters a year consisting of 12 rat pups, although 5-10 pups is more common.
- Rats reach sexual maturity after 9 weeks, meaning that a population can swell from two rats to around 1,250 in one year, with the potential to grow exponentially.
Dr Andy Brigham, General Technical Manager, Science and Service, Rentokil Initial, explains:
“If we were to do nothing we would be overrun by rats. Their breeding strategy is very different to that of humans. It is characterised by quantity over quality. They produce very large numbers of offspring on the basis that at least some will survive long enough to produce their own litters.”
“If there is sufficient space and food they have the potential to rapidly explode in numbers to exploit that, but mortality is high whenever food or space is limited, and factors such as disease, starvation, predation, and our own pest control efforts help to keep the rate of growth in check.”
The impact of rats on businesses and our cities
A report commissioned by Rentokil identified rats as the most destructive pest for businesses, causing machine downtime, electrical equipment damage and leading to, on average, 8 lost working days per year.
- JC Ehrlich, a Rentokil North America division brand, saw an 86% increase in the number of rat-related callouts from 2015 to 2016.
In almost any environment where there are humans, there are likely to be rats too. Some experts say that in major cities like New York and London, there are as many rats as there are humans. This is a frightening thought though more conceivable now, given what we know about their reproduction rate.
- At the end of 2016, Paris had to launch a major anti-rat campaign, which meant closing nine parks and green spaces as the city appeared to be overrun by rodents.
Knowing all this, would you act more quickly if you discovered a rat problem? Leave a comment below or follow us on Twitter @Rentokil and give us your view!
If you need help with rats, contact us today!