Rats have always been part of the cityscape, but in recent years the problem has worsened significantly. Rats are increasingly spotted in public spaces, waste areas, parks, basements, and even residential complexes.
But why is the number of rats in cities increasing so sharply – and which factors are driving this development?
This article shows the main reasons and explains what cities, businesses, and private individuals can do to keep the situation under control.
Why rats reproduce so rapidly in cities
1. Excess food supply
Modern cities offer rats endless food sources:
- Overfilled or open trash bins
- Food leftovers in public spaces
- Compost bins
- Containers & large kitchens
- Pet food outdoors
- Waste in parks
Rats need only about 20–30 g of food per day – and even the smallest scraps suffice.
2. Warmer winters & climate change
Mild winters mean:
- fewer winter losses
- faster reproduction
- longer activity phases
Rats have up to 5–7 litters per year with 6–12 young each – a climatically extended time window leads to an explosive increase.
3. Hiding places & structures favor them
Cities consist of countless structures that rats use:
- Sewers & wastewater
- Basement shafts
- Gardens
- abandoned buildings
- Gaps in masonry
- Construction debris & construction sites
These areas offer the perfect network of shelter and warmth.
4. Incorrect waste management
Common mistakes:
- overflowing trash bins
- unsealed lids
- torn garbage bags
- incorrect organic waste storage
- Construction areas with open waste
Even the most modern cities struggle with waste logistics – a paradise for rats.
5. Anthropomorphizing & feeding animals
Many people feed:
- Birds
- Ducks
- Hedgehog
- Outdoor house cats
But most of it ultimately ends up with rats.
A key factor for large-scale populations.
6. Sewer system: The invisible rat skyscraper
The sewer system offers:
- plenty of food from leftovers
- constant warmth
- Moisture
- undisturbed breeding sites
Thousands of animals often live here – the visible infestation is just the tip of the iceberg.
Why the problem continues to grow
Urbanization
More people = more waste = more food = more rats.
Undersized waste infrastructure
Older cities are not designed for today's waste volumes.
Fewer natural predators
Rats have hardly any natural predators in cities except birds of prey and foxes.
Resistances to rodenticides
In some regions, up to 70 % the rats are resistant to certain poisons.
✔️ Conclusion
Rats benefit from everything that makes up cities: many people, lots of waste, mild climate, and many hiding places.
The problem grows because modern cities offer ideal living conditions – and because rats adapt quickly.
However, the trend can be curbed with consistent waste management, structural prevention, and professional control. Only if everyone – city, businesses, and private individuals – cooperates, will the population remain manageable.
