Invasive Species Impact and Management

The lecture covers the concept of invasive species, their impact on ecosystems, and specific examples like the European starling and cane toad. It introduces Dr. Brian Roth, an expert on Great Lakes invasive crayfish, and discusses the legal definition of invasive species. The lecture explains the reasons for species introduction, the process of becoming invasive, and the effects on food webs and trophic cascades, using the reintroduction of wolves in Yellowstone as an example. Finally, it outlines strategies for managing invasive species.

What is the primary focus of today's lecture on invasive species?

• The diet of native swans

• The history of the Great Lakes

• The impact of invasive species on ecosystems

• The migration patterns of swans

Which swan species is invasive in the Great Lakes region?

• Trumpeter Swan

• Mute Swan

• Whooper Swan

• Black Swan

What is a key characteristic of invasive species?

• They are always native to the area

• They are non-indigenous and can cause harm

• They are always beneficial to human health

• They cause no harm to the environment

Why were European starlings introduced to North America?

• For agricultural purposes

• To recreate birds from Shakespeare's plays

• To increase biodiversity

• To control insect populations

What was the unintended consequence of introducing cane toads in Australia?

• They controlled the beetle population

• They reduced the number of native toads

• They improved sugar cane growth

• They became a major pest

What is one reason species are introduced into new environments?

• To reduce water levels

• To eliminate native species

• To decrease biodiversity

• For recreational purposes

How do invasive species typically impact native species?

• By providing additional food sources

• By reducing competition

• By competing for resources

• By increasing habitat space

What is a trophic cascade?

• A direct interaction between two species

• A series of indirect effects in a food web

• A type of invasive species

• A method of species removal

What was a significant effect of reintroducing wolves to Yellowstone?

• Increase in biodiversity

• Decrease in berry production

• Increase in elk population

• Reduction in woody plants

What is the best time to address invasive species?

• Before they become established

• During their introduction

• After they are well-established

• Once they dominate the ecosystem