Rats can become a problem at any time, but especially so when our climate is rapidly changing.

We know climate change is happening, the ship that once said ‘it may be natural, and it may not even be happening’ has well and truly sailed. So, we are now in the middle of a massive push to try and slow the change and looking at how the change however severe may affect us.

There could be thousands of different ways that climate change may affect our lives in the UK, and many would be different to the things that may affect someone’s life in Florida or Bangladesh, for example. Many issues will be common, and many will be unique to certain areas. Rats are a common problem for most parts of the world so how could climate change affect rat behaviour and populations in the UK and across the world?

Before we look at some of the issues around climate change and rats it is important to consider the rat problem as a whole. These social and intelligent animals have long made our urban and rural environments their home. As with many pest species they find easy food, warmth, safe breeding areas and shelter in and around our buildings and lives in general. While they don’t cause problems physically, apart from being something a lot of people hate, rats do tend to carry a lot of nasty things with them. They can carry E. Coli and Weils disease otherwise known as Leptospirosis (both of which can kill), as well as Salmonella and other bacteria. They can also carry fleas and ticks too, so they are a problem. As well as the safety aspect rats can also do a lot of damage. They can work through massive supplies of stored food, damage insulation, wiring, walls, doors and more. So, while they may, as animals, be social, clever and cute in the right circumstances we cannot live with them unchecked.

Living Side-by-Side

While we cannot live with rats, they are very common. Much of the time they remain in low enough numbers or out of our way enough to not be an issue. It is when their population gets too big or they set up home too close to us that we have a problem. But there are other times when their presence is made known when it otherwise would go unnoticed, and that is in bad weather. During periods of heavy rain and flooding rats will leave their homes and seek shelter in other places. The same can happen in very cold periods and when food becomes scarce.

Climate Change in the UK

As mentioned earlier, climate change will have differing effects in different locations. The general feeling is that in temperate locations like the UK we will see more extreme weather, including wind and rain, leading to more flooding and a general rise in temperature for the rest of the year … . So what will this do to the rats?

Rats and Climate Change

If we see more flooding there will be more rats trying to find shelter in our buildings and our homes; certainly in cities and towns. But there are other factors at play here too! In warmer weather rats tend to breed more rapidly. This makes pretty good sense, there is normally more food around in the warmer months and babies are less at risk from cold. So not only could we see rats looking for shelter from extreme weather but there could well be more of them as well! Not a great situation. Mark Stanford, a pest expert and owner of Empire Pest Control sums up the rat situation:

‘Warmer weather increases breeding; floods and cold weather brings them indoors’.

Evolution in Fast Forward

As with climate change, most people accept evolution as a fact. The simple idea that successful traits in the offspring of an animal may help it to survive and thrive and that these traits can be genetically passed down to subsequent offspring is the basis. These traits then propagate throughout a population over time to become the norm while other new traits can spring up at any time. Evolution responds to adverse conditions because the populations are under pressure, times are tough so small changes can mean the difference between life and death. But the speed of evolution is also dependant on the time it takes for a species to breed and raise offspring to breeding age. Rats can do it very quickly. We don’t need to go into the stats but rest assured, rats breed fast and the young can breed very quickly. This becomes a problem when we look at rat control. There are lots of ways to get rid of rats and many of them involve poison and traps. There is a real possibility that rats may become immune to poisons and learn to avoid traps, and the faster rats breed the faster evolution will help them do it.


The potential reality of climate change for rats could mean increased breeding leading to increased adaptations to control methods, which mean more breeding and then a need to escape flooding by coming into human contact. Rats also feed on our waste so the more waste we produce and leave lying around the better they do.

It is not all bad, this is an extreme scenario, but it is a real issue that should be taken seriously and yet another reason why fighting climate change is critical to the future of the human race. While rats aren’t likely to take over, they could become a very serious problem and cost even more money to control in London, the UK and other countries than they do now.

Image by Varga from Pixabay