Understanding Invasive Species

These flashcards cover key concepts and case studies related to invasive species as discussed in the lecture.

What defines an exotic species?

An exotic species is a species introduced either accidentally or deliberately by human actions into places beyond its natural geographical range.

What is the definition of an invasive species?

An invasive species is an alien species whose introduction causes or is likely to cause economic or environmental harm or harm to human health.

What impact can invasive species have on native ecosystems?

Invasive species can severely disrupt local ecosystems, leading to extinction or extirpation of native species.

What was a significant cause of bird extinction in Guam?

The introduction of the Brown Tree Snake, which led to the loss of nine native bird species.

How fast did the Brown Tree Snake expand its range in Guam?

The Brown Tree Snake's range expanded about 1.6 km (1 mi) per year.

What was the situation regarding the Bridled White-eye in Guam?

The Bridled White-eye was last seen in 1983 and is now extinct.

What are the characteristics of successful invasive species?

Successful invasive species often have high reproductive rates, short generation time, and high dispersal rates.

How do Burmese Pythons affect the Everglades ecosystem?

Burmese Pythons eat virtually everything they can swallow, leading to a 99% decline in many native mammals.

What characteristics make a community more susceptible to invasive species?

Communities with low diversity of native species and absence of predators are more susceptible to invasions.

Why was the Brown Tree Snake's introduction to Guam particularly harmful?

It was inadvertently introduced in military shipping cargo and caused the extinction of several native species.

What happens to the native fauna in areas with high invasive species presence?

The native fauna often face declines in populations or may become extinct due to competition and predation from invasives.

What is the reproductive capability of Snakehead fish?

Snakehead fish can lay around 15,000 eggs per spawning and can spawn up to five times a year.

What role does human activity play in the dissemination of invasive species?

Human activities often lead to the accidental or deliberate introduction of invasive species into new environments.

What is a polyphagous species?

A polyphagous species is one that can eat a broad diet consisting of various food sources.

How does climate influence the spread of invasive species?

Invasive species can thrive in communities that match their climatic needs.

What is the significance of the Asian Carp invasion?

Asian Carp alter aquatic food webs by feeding on native mussels and snails and can disrupt ecosystems.

What key features make communities invadable?

Characteristics include absence of fire in evolutionary history and anthropogenic (human) disturbance.

Why did scientists initially rule out disease as a cause for bird decline in Guam?

Testing for diseases and parasites came up negative, leading to the investigation of other factors.

What is the ecological impact of Kudzu as an invasive species?

Kudzu can overwhelm native plants, leading to reduced biodiversity.

What conclusion can be drawn regarding types of invasive species likely to cause damage?

Only a relatively few invasive species cause serious damage, but some have devastating impacts on native species.