Cynthia is a nature enthusiast with a passion for ecosystem conservation.
What Is an Invasive Species?
Did you know that Siberian chipmunks are breeding in the wild in Belgium and France? They are now what is known as an invasive species in these countries. An invasive species is any animal, insect or plant that is not indigenous to the area that it has moved into and is damaging the local eco-systems and habitats and forcing out the native flora and fauna. It is a big problem in many countries of the world, and there are no easy solutions.
What Causes Invasive Species to Appear?
So how does a species like the chipmunk get a foothold in another area or country? It can happen in many ways. Human migration is one cause. When people pack up to build a life in a new country or even on a new continent they tend to take their domestic pets and livestock with them, introducing cats, rabbits, dogs, cattle, sheep and goats into regions where they might not have been present before and where they are able to successfully compete against existing species and drive them out.
Some species, like rats and cockroaches, are notorious stowaways and hitch rides on ships and other transport to destinations around the world. This is how the great plague was spread across Europe in the 14th century; it arrived on the fleas living on the rats that were living on the ships that were trading across the Mediterranean and Atlantic coasts.
The trade in exotic pets is another vector. People buy exotic pets, including snakes, spiders, birds, turtles, fish and iguanas, and when they grow too big or they do not want to or cannot care for them anymore, they release them into the wild. If the climatic conditions are suitable and there is an adequate food supply, they can breed and spread.
Groups of animals also sometimes escape from zoos, wildlife parks and private collections and form breeding colonies, like the famous colony of wallabies that took up residence in the Peak District of Derbyshire until an extremely cold winter in 1963 wiped the majority of them out. T
here are also examples of species being introduced by governments to create a natural predator for a species that is regarded as a pest—either an indigenous species or another introduced species—and these experiments can go disastrously wrong. Probably the best example is the cane toad, introduced into Queensland, Australia, in the 1930s. Cane toads were unsuccessful in controlling the pests in the cane fields that they were introduced to deal with but have bred very rapidly and are now expanding into ever-larger swathes of Australia, including the Northern Territory and New South Wales, depleting local species as they go.
Siberian Chipmunks in France
So what is going on in France? Parts of Belgium and Northern France are being overrun by an invasive species—the Siberian chipmunk. These cute, striped, friendly rodents began to be imported into Europe from Asia in the 1970s to be sold as pets, and in 1980, 17 individuals were released into a park in Brussels in Belgium. They bred successfully, and it is currently estimated that there are now more than 100,000 of them living in the wild in France.
A chipmunk can be bought for as little as 10 Euros in French pet shops, and the huge numbers now found in the woods around Paris are attributed to families who bought one as a pet and then released them when they did not want them anymore.
Chipmunks Can Carry Disease
Chipmunks are listed on the European Union’s list of 100 most-invasive species and can be carriers of both rabies and Lyme disease. Rabies is a virus that is usually spread by a bite from an infected animal or from a scratch that punctures the skin. The rabies virus attacks the nervous system, causing symptoms of headache, fatigue, high temperature, hypersensitivity, hyperactivity, seizures, hallucinations and paralysis. Death can be caused by a sudden cardiac arrest, or the infected patient may sink into a coma.
Lyme disease is carried by ticks that are found on the invasive chipmunks and is passed on when the tick is transferred to a human and bites them. The initial symptoms are a rash, fever, headaches, swollen glands and muscle and joint pains. For some sufferers, they will develop what is known as neuro borrelia between one and five weeks after having been bitten, which affects the central nervous system. The symptoms can include back pain, nerve numbness, fever, stiffness in the neck and headaches and can develop into a chronic damaging of the nervous system. In addition, Lyme disease can re-emerge years later as both swelling and discolouration of the skin, Lyme arthritis or inflammation of the heart.
Danger of the Chipmunks Reaching the UK
The rapidly expanding population of chipmunks will also compete with local species for food and habitat. The chipmunks are not nervous of human contact, and as they are easy to approach, it makes the chances of someone contracting a disease from them much higher.
There are huge concerns that this highly invasive species will make it to the United Kingdom, threatening both the human population and the native species. Officials are concerned that they will be bought in pet shops in France and smuggled into the UK or simply captured in parks or woodlands and illegally brought into the country. In addition, the nearer to the French coast that the chipmunk spreads, the more likely it is that they could find a way onto a train, truck or car that is travelling under or across the Channel and end up in the United Kingdom.
How can this invasive species be stopped from spreading across Europe? Wildlife experts are pressing for a ban of chipmunks in pet shops, and tourists need to recognise the dangers of trying to take animals across borders illegally.
This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.
Tim on June 14, 2019:
Will mouse traps work
CMHypno (author) from Other Side of the Sun on July 26, 2015:
Thanks for reading and replying Virgina. Any animal that is introduced can be a pest unfortunately, through no fault of their own, because they did not evolve within the local eco-system and so do not have a place within it.
Virginia Allain from Central Florida on July 13, 2015:
They are indeed prolific. Although native in the northern part of the U.S. they often fall into the pest category for their burrowing which can undermine steps, decks and garden walls.
I've trapped with a Havahart trap 19 in my yard just this summer.
CMHypno (author) from Other Side of the Sun on January 12, 2013:
shyanne did you actually read the article? Yes chipmunks are cute, but like most species when they are invasive they are potentially destructive and can pass on disease to indigenous species and even humans.
shyanne on January 11, 2013:
CMHypno (author) from Other Side of the Sun on July 30, 2009:
Hi emohealer, thanks for the great comment. I think their cuteness and friendliness is what makes them so potentially dangerous
Sioux Ramos from South Carolina on July 29, 2009:
Who knew, I just always thought they were cute, not so much now.