As of September 30th, pest control company Anticimex had carried out around 41,000 call-outs in the hunt for rats across Sweden – a record for this time of the year. The firm expects their final numbers at the end of the year to be 57,000, which would be an increase of 264 percent compared to 2011.
Nomor, a competitor, also expects to have a record year. While the stats do not necessarily guarantee that there are more rats, most evidence points to that.
"The problem we're seeing now is just the tip of the iceberg, above all in the big cities. But in Stockholm for example we have housing construction and detonations for infrastructure that make the rats move in a way that you do not see otherwise, which means an increase in reports," Andreas Olsson, head of operations at Nomor told news agency TT.
In general the number of reports tends to increase in the autumn, when rats become more visible in residential areas. In part they move to gardens in order to eat fruit and use natural habitat like bushes, but they also try to get into houses in order to seek out warmth for the winter.
Håkan Kjellberg, pest expert at Anticimex, says people could do more to combat the problem, and would like to see a harder line taken from authorities against those who are careless.
"We were out the other day at a site where there was a lot of trash and clutter in the back garden. When everything is left sitting it attracts rodents and they establish a population. It just hits other people while there are no consequences for the person. The authorities need to act more, including by handing out fines," Kjellberg told TT.
Easy access to food from humans also means it is becoming more difficult for exterminators to catch rats in their traps.
"It's important to eliminate sources of food. If you have bins and containers outside, make sure they have a properly sealed lock that covers the entirety. You also need to have systematic cleaning so that scents don't attract the rats. There are a lot of small things that everybody can do to resolve the problem," Nomor's Olsson noted.
In the south of Sweden, a construction boom has been cited as the reason for a rat boom in Skåne, where the number of call-outs to deal with the pests are up compared to 2016.
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And in Gothenburg, call-outs are up by almost 20 percent over the last three years. They are particularly noticeable at Gothenburg Cathedral in the centre of the city.
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