Invasive Species Overview

This set of flashcards covers key concepts related to invasive species, their impacts, pathways of introduction, and specific examples discussed in the lecture.

What is an invasive species?

A species intentionally or unintentionally introduced by humans outside of its native range that expands aggressively and negatively impacts the invaded ecosystem.

What is one example of an invasive species mentioned?

Privet (Ligustrum), an invasive shrub.

What is the second greatest threat to biodiversity globally?

Invasive species.

How many documented invasive species were there in Texas as of 2011?

More than 800.

What are the two criteria for inclusion in the IUCN's list of the 100 worst invasive species?

Ecological and economic impact.

What is the Giant Salvinia?

An invasive plant introduced from South America as an aquarium plant, first recorded in Texas in 1998.

What is a pathway of invasion?

The means by which invasive species are introduced to new areas, either intentionally or unintentionally.

Name one unintentional pathway of invasion.

Ballast water used in ships.

What are the economic damages caused by invasive species in the U.S. annually?

$120 billion.

How do invasive species affect the diversity of native species within communities?

They can increase alpha diversity but often decrease beta diversity due to dominance by invasive species.

What impact do zebra mussels have on native mussels?

Zebra mussels compete with native unionid mussels in eastern U.S. watersheds.

How can invasive species affect the morphology of native species?

Invasive species can cause native species to develop thicker shells or change physically due to predation.

What behavioral change was observed in native pollinators in Europe?

Native pollinators prefer invasive Asian Impatiens over native wildflowers.

What evolutionary impact can invasive species have?

They can drive evolution in native species, such as the native checkerspot butterfly preferring European Plantago over native wildflowers.

How do invasive species affect nutrient cycling?

Some invasive species, like the New Zealand mud snail, can consume a large percentage of gross primary production and produce significant amounts of nitrogenous waste.

What is one major impact of the invasive European cheatgrass on U.S. prairies?

It increases fuel loads and the intensity of fires.