City dwellers have been getting some unexpected new neighbors— and the surprising influx is taking place right beneath their feet…

One of the biggest invasions of the past few decades is taking place in some European cities— yet most of the residents don’t even realize it’s happening. id digs up the dirt on the new rulers of the urban underground: wild rabbits.

The location could be better. And at first glance the size is nothing to write home about. The new building site offers just 625 square feet of space situated right in the middle of two four-lane roads and in the shadow of three large apartment towers. Yet the new residents feel happy and contented here. Because for this colony of 20 wild rabbits, the traffic island in downtown Hamburg, Germany, offers ideal living conditions. Like the millions of other European wild rabbits, these also prefer the hustle and bustle of the big city to the peace and quiet of the countryside. But why? What is attracting more and more bunnies to big cities?

A ONE- BEDROOM APARTMENT INSTEAD OF A MULTIFAMILY HOUSE

Tens of thousands? Hundreds of thousands? Nobody knows exactly how many wild rabbits have relocated from the country to the city in recent years. However, the fact is: In the parks, canals, cemeteries, and traffic islands of some of Europe’s largest metropolises, the number of wild rabbits is skyrocketing. The tunnels and living quarters of their underground structures, which can be up to 15 feet deep, extend across hundreds of feet through the subsurface of the cities. (See the graphic on the next page.) “The animals have learned that there are good living conditions in the urban areas,” explains wildlife expert Andreas Kinser. The advantages for the intrepid little lagomorphs: Whereas the rural regions offer only monotonous monocultures, in the cities the rabbits can find a diverse array of food items, including all manner of garbage. In addition, the tall concrete blocks and utility poles offer sufficient protection from predators such as birds of prey, and the ground is much looser than it is in the country, making it perfect for digging out subterranean housing systems. And biologists at Germany’s Goethe University Frankfurt have made a fascinating observation: They discovered that wild rabbits, like humans, tend to live in small groups or even in individual dwelling units in the cities while counterparts residing in rural areas will form large families that can comprise more than 50 members.

It is unclear how many wild rabbits have yet to conquer the big cities and how they’ll spread out through the landscape. But these animals, which originated in southern Europe and moved northward at least 200 years ago, are masters of invasion—something they’ve already proved in Australia: A dozen wild rabbits were released there 150 years ago; today 300 million live on the continent, outnumbering humans 13 to 1…