Final answer:
Invasive species threaten ecosystems by altering habitats, out-competing native species, introducing diseases, and causing economic losses. Examples include the transformation of forests into meadows in Tierra del Fuego by beavers and the domination of native fauna by species like the emerald ash borer in the US.
Step-by-step explanation:
The threats that invasive species pose to ecosystems are profound and multifaceted. Invasives can modify entire ecosystems, such as changing forests into grasslands or vice versa, which affects the native species that previously thrived in those habitats. An example is how North American beavers introduced in Tierra del Fuego have transformed forests into meadows. Invasive species can also out-compete or predate on native species, potentially leading to their decline or extinction, as seen with the Nile perch in Lake Victoria.
Invasive species are often accompanied by parasites and diseases, which can lead to the decline of native species, as experienced by the European crayfish populations. Moreover, these organisms can have significant economic repercussions, acting as pests in agriculture and causing extensive damage. Research has shown that climate change may exacerbate the impacts of invasive species, making their control and management even more challenging.
In the United States, invasives like purple loosestrife, zebra mussel, common buckthorn, garlic mustard, and the emerald ash borer have drastically altered ecosystems, threatening aquatic environments and forests. The European starling competes with native birds for nesting sites, showcasing how these species affect native fauna at multiple levels. Integrating studies on invasive species and their impacts is essential for preserving biodiversity and ecological integrity.