Alien Invaders; The Threat of Invasive Species

The EEA reported that invasive species are “a growing pressure on the natural world which are extremely difficult to reverse.” Especially since ecosystems are already weakened by other man-made threats, such as pollution and climate change.

Image: By H. Zell (Own work) [GFDL (http://www.gnu.org/copyleft/fdl.html) or CC-BY-SA-3.0 (http://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons

Invasive species are a huge threat to biodiversity the world over. A report produced by the European Environmental Agency (EEA) shows the high cost, to native species and to taxpayers, of invasive “aliens” in Europe. And many of those species are heading our way.

The EEA report, released last week and entitled The Impact of Invasive Species in Europe, states that over 10,000 non-native species now have a foothold in Europe. Of those, at least 1,500 are deemed to be “invasive,” meaning that they are known to have negative ecological or economic impacts. In total, it is now estimated that they cost us at least £10 billion every year. The UK is among the worst affected countries by invasive species, with France, Italy and Germany also showing high rates.  The EEA reported that invasive species are “a growing pressure on the natural world which are extremely difficult to reverse.” Especially since ecosystems are already weakened by other man-made threats, such as pollution and climate change.

It is climate change that may contribute to the spread of invasive species, since growing international tourism and trade in recent decades has contributed to the introduction of foreign species. Although many non-native species have caused no significant harm, or have even been beneficial such as the potato from South America, some cause real damage and can have complex and unpredictable consequences. The Asian Tiger Mosquito has been linked to the transmission of more than 20 diseases, such as yellow fever and dengue fever. It was linked to an outbreak of the chikungunya virus in Italy in 2007, and with our warming climate could expand its range northwards and reach the UK. Ragweed, originally from North America, is also spreading north within Europe thanks to climate change, and is bringing with it health problems to sufferers of hay fever and other allergies. Spanish Slugs are now present in the UK, affecting gardens and horticulture, since plants make up part of their diet. The EEA also urges better assessment of fast-growing species before being used as biofuel, citing the example of Japanese Knotweed. Growing by 30cms per day and with a root system reaching a depth of 3m into the soil and spreading up to 20m, it not only threatens slower-growing plants by blocking out sunlight, it is also almost impossible to eradicate once it is established.

The report was released ahead of a high-level meeting at the European Parliament (organised by IUCN and Birdlife) to consider measures that could be taken to mitigate the present and future threats of invasive species. The EEA writes that the best way to tackle the threat invasive species pose is through a “combination of preventative measures, early detection and rapid response to incursions, with permanent management only as the last option.” As our climate continues to change, more and more species are spreading to increasingly hospitable areas, and these actions become ever more urgent.

Tags:

No comments yet.

Leave a Comment

Your email address will not be published.*

Tick the box or answer the captcha.

You might also like

  • Pine Martens: The Comeback

    Small populations survived in Wales and areas of northern England at very low densities, but the only viable populations left could be found in the North West Highlands of Scotland where persecution pressures were less.

    By Alex Taylor
  • The Ecological Vs Political

    Delivery is often more ecologically defined, so perhaps we’re just stuck with political dimensions until we get the buy-in we need.

    By Guest Bloggers
  • Orcas and Dolphins in Captivity

    Capturing a wild animal is traumatic for any species but for social species like orcas and dolphins it is likely to be a horrifying event that may last a life time.

    By Guest Bloggers
  • Adder Decline

    Reductions in population numbers prompted the UK government to pass legislation in 2007, which prioritised the protection of common toads and all UK reptiles.

    By Alex Taylor