Help me. Invasive species? what's that exactly?

Answer 1

The term invasive species refers to a subset of those species defined as introduced species or non-indigenous species. Invasive species can alter ecological relationships among native species and can affect ecosystem function, economic value of ecosystems, and human health. A species is regarded as invasive if it has been introduced by human action to a location, area, or region where it did not previously occur naturally (i.e., is not native), becomes capable of establishing a breeding population in the new location without further intervention by humans, and spreads widely throughout the new location. Natural range extensions are common in many species, but the rate and magnitude of human-mediated extensions in these species tend to be much larger than natural extensions, and the distances that species can travel to colonize are also often much greater with human agency (Cassey et al. 2005). The majority of introduced species do not cause significant ecological change or environmental harm because they exist primarily in habitats already subjected to intensive human alteration; such species may not be considered 'invasive'.

Answer 2

An invasive species is a species occurring, as a result of human activities, beyond its accepted normal distribution and which threatens valued environmental, agricultural or personal resources by the damage it causes.

A species is regarded as invasive if it has been introduced by human action to a location, area, or region where it did not previously occur naturally (i.e., is not native), becomes capable of establishing a breeding population in the new location without further intervention by humans, and spreads widely throughout the new location. Natural range extensions are common in many species, but the rate and magnitude of human-mediated extensions in these species tend to be much larger than natural extensions, and the distances that species can travel to colonize are also often much greater with human agency (Cassey et al. 2005). The majority of introduced species do not cause significant ecological change or environmental harm because they exist primarily in habitats already subjected to intensive human alteration; such species may not be considered 'invasive'

.Invasive species are infiltrators that invade ecosystems beyond their historic range. Their invasion threatens native ecosystems or commercial, agricultural, or recreational activities dependent on these ecosystems. They may even harm the health of humans.

Humans have assisted with this invasion for centuries. This assistance has been either intentional or unintentional. Intentional introductions involve the deliberate transfer of invasive species into native ecosystems. An example of this would be someone who disposes the contents of their home aquarium into a waterway. Unintentional introductions occur when invasives are transferred through accidental means. For instance, one of the ways that zebra mussels have spread is through ship ballast water, which is used to keep ships stable in the water.

Invasives are transferred through numerous vectors including ships, boats, barges, aquaculture, agriculture, nurseries, or connected waterways. Through these and other vectors, thousands of invasive species have been introduced into this country, costing the economy billions annually.

Answer 3

Invasive species are plants and animals which force out the native species of an ecosystem. One example is the kudzu vine which has taken over in many parts of the South.