Invasive Species

What is an Invasive Species? Plants, Animals or Micro-organisms that are introduced into an environment to which it is not native and causes harm. Cows and some ornamental flowers are not native to all areas but are not invasive because they do not cause damage.

Brown Tree Snake Came to US on ships from Guam after WWII Kills off species with its tremendous appetite

Examples of why species are introduced to a new area Some plants used to control soil erosion Ornamental plants used in landscaping around homes European birds were brought to the US to make colonists feel at home Fish used to stock ponds/streams for game fishing Exotic pets escaping or being released

Indian Myna Native of India Introduced to world to control insects Takes over ecosystems and reduces biodiversity

How do Invasive Species Enter a New Environment? Illegal or legal importing Exotic Pets Travelers Weather Patterns Tides Water Current Migratory Animals

An Invasive Species of PA Zebra Mussel Accidentally released by boats Eats native organisms’ food sources Clogs pipes and attaches itself to boats and animals

Zebra Mussels

Another PA Invasive Species Hemlock Wooly Adelgid Small insect Accidentally introduced from Japan/China Kills Hemlock trees which are used for providing habitat and shading streams for fish

What is effected by the Invading Species? Biodiversity Agriculture Forests Lakes, Ponds, Rivers, Streams, Ocean Environment Health Economy

Why are they harmful? They have no natural enemies Reproduce quickly and freely Use natural resources intended for the native organisms Destroy Crops Alter the Food Chain Force out native species