Masked invaders: The raccoon’s quiet takeover of Europe
You might not expect a North American species to take root in Europe, but the northern raccoon is doing just that. With its distinctive black face mask and dexterous paws, this inquisitive animal is steadily making its way into the continent’s forests, farmland and even urban landscapes.
It all started in the 1930s when raccoons were introduced to Germany – partly through the fur trade and partly because some people thought it would be interesting to release them into the wild. Free from natural predators, fuelled by abundant food and remarkably adaptable, they began to thrive. Today, raccoons are well established across much of central Europe and have also made their way into Belgium.
In Wallonia, the southern part of the country, there are now an estimated 60,000 raccoons, mostly living in wooded areas. They may not be easy to spot – especially in daylight – but they are out there, and their numbers are growing. In some places, raccoon populations have reached astonishing densities of up to 100 animals per square kilometre.
It may sound like a conservation success story: an adaptable species finding a new home. But as is often the case with non-native species, the reality is more complicated.
Raccoons are opportunists. They eat almost anything – fruit, insects, small animals, eggs – and this has consequences for native wildlife. In ecosystems where raccoons don’t belong, they can upset fragile balances by preying on birds or competing with native species. But much of the concern today isn’t just about their ecological impact. It’s about what they might be carrying.
Diseases and parasites
In their native North America, raccoons are known to carry a number of diseases, including rabies and distemper. They’re also notorious for carrying Baylisascaris procyonis, better known as the raccoon roundworm. This parasite doesn’t just affect raccoons. If its microscopic eggs end up in soil, water or on surfaces touched by curious children or pets, they can cause serious illness. Although these cases are rare.
Until recently, European researchers believed that these health risks were fairly limited on this side of the Atlantic. Early studies found low rates of infection in raccoons here. But this view is beginning to change. A recent German study found that almost 95% of raccoons tested were carrying the raccoon roundworm. That’s a surprisingly high rate – even higher than what’s found in some parts of North America.
Why the sudden jump? One possible explanation is urbanisation. The study found that raccoons living in cities or on farmland tended to have higher parasite loads than those in wilder, more natural areas. Urban raccoons have easy access to food – whether from compost bins, pet food bowls or discarded leftovers – and they often live in larger numbers, which can help the parasite spread more easily.
Blind spot
Despite these findings, raccoons remain something of a blind spot in European wildlife policy. In Belgium, for example, the species is officially managed, but mainly because of its impact on biodiversity – not because of health concerns. But experts warn that this could change. As raccoons continue to expand their range, they could become important carriers of not only foreign parasites such as roundworms, but also local ones.
Researchers are urging the collection of more data: on raccoon movements, population growth and likely patterns of spread. With better surveillance and predictive models, future outbreaks could be anticipated – or even prevented.
For now, the raccoon’s European adventure is a story yet to be written. It’s a reminder that even charming animals can carry unexpected baggage – and that in an interconnected world, no invasion is ever truly local.
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