Invasive and Endemic Species

What are invasive species?

Species that were introduced by humans, either deliberately or accidentally

Why are invasive species not effectively controlled?

Due to the absence of natural predators.

What are endemic species?

Species which occur naturally in an ecological niche in an area

What are endemic species regulated by?

Density-dependent factors

Nutria

Imported to France and Germany for their fur but escaped to Switzerland living along riversides

What is the impact of Nutria on local ecosystems?

Nutria destroys valuable wetland habitat by burrowing deep wholes and creates economic costs through crop loss

What is the impact of Nutria on local species?

Takes away livable space of endemic species and transmits parasites and bacteria to local species

Japanese Knotweed

Grows up to 3m with a very extensive root network

Where does the Japanese Knotweed grow?

Close to riverbeds which pushes back endemic plants that are better suited to the terrain

Where does Japanese Knotweed grow between?

Bricks and walls causing breakage and destruction

Box-tree Caterpillar

What do young caterpillars eat?

Parts of the chlorophyl

What can older caterpillars defoliate?

An entire plant in a short period of time

Himalayan Balsam

Produces very quickly and leads to a high density of plant growth

What is the effect of Himalayan Balsam on biodiversity?

Reduces biodiversity, and facilitates erosion due to resource competition with local plants along embankments and rivers

What does it appear as in forests?

A pest reducing natural tree growth of local species