Introduction

"We must make no mistake: we are seeing one of the great historical convulsions in the world's fauna and flora."
-- Charles S. Elton, 1958.

We are under invasion by aliens. These “aliens from earth” are species which are introduced into areas where they did not previously occur. Because global travel and commerce are increasing, the number of introductions and their potential impacts is also on the rise. The biology and ecology of these invaders, and the roles they come to play in the areas where they have been introduced, is the subject of this web site. During your exploration here, you will learn about ecological principles that affect the outcomes of species introductions. You will then explore how non-indigenous species get to new habitats, the benefits and costs of species introductions, and what you can do to stem the tide of alien invasions. This site is designed to allow you to play the role of scientist and to test various hypotheses about alien invaders. This site is also designed to provide information on what makes alien invaders successful in their new habitats. After learning about them, we invite you to become an active participant in reducing the impact of alien species by teaching you how to tell a native thistle from an exotic one.

To begin, click on the links to the left or choose a topic from the list below.

What are exotic species?
How are exotic species introduced?
What are the impacts of exotic species?
Basic ecology