Threat: Invasive Species


What is an invasive species? These are animals or plants, which are not native (alien) to a specific ecosystem, and so their introduction causes or is likely to cause damage or harm to the environment, human economy or public health. They have the ability to invade certain areas, taking over the land, food and shelter of the natives and making it their own. They even lead to the extinction of native species!  Invasive species should NOT be confused with introduced species.


So, where do invasive species come from?

One consequence of globalization is that in addition to trade, transport and tourism all moving people and products across the globe, wildlife has also been transported in the process.   While some invasive species are introduced intentionally for the purposes of aquaculture, food security and agriculture, and biological or pest control, others can be introduced accidentally from pets that have escaped or were released into the wild.

They can enter new environments through many routes:

- Some are transported to new places and established purposely, but the consequences are unexpected, while some invasive species are brought in as unsuccessful attempts to control other invasive species. This results in the area having two invasive species to deal with.

- Some have also been introduced accidently through cargo shipments and with these alien species comes diseases being introduced to the ecosystem, which can also be harmful to people if the species are poisonous and/or dangerous. Therefore, the threats of invaders include causing localized extinction or decrease in population size because they compete for water, food and sites to breed.


  • Invasive species can exploit a resource that native species cannot use, allowing them to take hold in the new environment and some can change the environment in a way that makes it more favorable for them, but less favorable for natives, which is called ecological facilitation. 


An example of invasive species in the UAE is the Indian house crows spotted in Abu Dhabi, which can cause significant damage to the ecosystem by impacting island breeding birds by eating the young and eggs apart from the high risk of disease introduction they bring. Another local example is the mesquite tree, a Central American tree species that was intentionally brought to the UAE to help forestation efforts, but instead it is growing in dense forests, destroying farms and native flora such as the ghaf, the national tree of the UAE.


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