Believe it or not, after habitat loss, invasive species are the second most significant threat to biodiversity. In a new environment or ecosystem, invasive species become predators and compete with the existing species, to the extent that they are inhibiting the survival of native plants and animals! Once species find the right conditions, they will essentially survive, spread and reproduce and cause havoc in the new area. Here we explore the most suppressing issues of invasive species around the globe.
It’s hard to imagine that globalisation isn’t just the movement of people, but wildlife too! Although most species recolonise and grow, some newly introduced species do not become established permanently as they can find themselves in the wrong type of climatic and competitive conditions, unable to produce enough offspring to sustain a population. The opposite is true for species that can thrive at their new location as they almost have the correct biological traits to allow for recolonization.
Flickr | Lou Feltz
The most significant consequence of invasive species is habitat loss. An example is the Canadian beaver; after relocation to the Tierra del Fuego region of South America, they have multiplied and are causing serious threat to the trees. Such tree species are not adapted to beaver activity and most cannot grow back after constant gnawing by beavers. It has now come down to a serious issue of deforestation, resembling a bulldozer having demolished the area.
This destruction almost has a domino effect on the rest of the environment. The beaver activity has created flooding from the lack of trees, altering the nutrient cycle in forests, where unfortunately, the invasive species are thriving in such conditions.
Flickr | Don Shall
Even populations of tiny insects can have a disastrous effect on a habitat. The hemlock woolley adelgid is an insect originally from Asia that has invaded parts of the Eastern United States. Unfortunately, their migration has killed up to 80% of hemlock trees. This leaves crucial impacts for the species that rely on the trees, consequently facing extinction. The same scenario has occurred in the South-eastern United States. The Kudzu vines were imported from Japan in the 19th Century as an erosional control, but this plan backfired! The vine has since become invasive in forests, and has overgrown to an uncontrollable scale, thus preventing sunlight from reaching the trees. In fact, the Kudzu vines ability to overgrow and destroy forests has earned a nickname “the vine that ate the South!”
Flickr | David Redman
Killing Endemic Species
Imagine somebody invading your own home and forcing you to move out! Well this is essentially what invasive species are doing to the innocent native species. Once of the most fierce invasive species is the Burmese python which is now a top predator in the Everglades, Florida. Unfortunately, these pythons have decimated local bird and mammal species; they have the capacity to consume deer’s and even alligators, in fact they can practically consume any animal they encounter! There is recent concern that the Burmese Python could drive some animals towards extinction, which makes us think whoever introduced this reptile to Florida regrets it!
Unfortunately, it has been proven difficult to manage the colonisation of the Burmese Python in the Everglades National Park due to their abundance and obviously difficulty locating them. It’s one of the most suppressing environmental issues in America, and a threat to biodiversity on an extreme scale.
Flickr | Florida Fish and Wildlife
In the United States, the consequence and control of invasive species costs $120 billion annually. Removing the kudzu vines growing on power lines has estimated to $1.5 million alone! The catastrophe that invasive species are creating is not stressed enough. Another example is the zebra mussels in the Great Lakes, which have clogged up the water intake at treatment facilities, putting a strain on costs for maintenance and repairs. At the same time, the Great Lakes Lampreys have demolished fishery stocks, and are now not profitable.
Flickr | Taber Andrew Bain
Regrettably, no region or habitat on this planet is immune from the threat of invasive species. It is so easy for non-native species to comfortably find a new habitat and colonise it to the extent that native species are threatened. As already discussed, the cost of such species is extraordinary. The Nature Conservancy aims to control the threat posed by non-native plants and animals through a combination of prevention, early detection, eradication and restoration initiatives.