Detection and Eradication of Introduced Species

What is an early detection and rapid response system? Invasion biology shares a philosophy with medicine—it is far better to prevent a harmful event or disease than it is to rely on the hope that some prescribed cure will be successful. Still, nonnative species...

Prospect—The Homogeocene?

What is biotic homogenization? Multitudes of species have been introduced to all parts of the earth (even Antarctica has about 10 established invaders) in what ecologist Francis Putz has branded the Homogeocene. The main change marking the end of the Holocene (the current epoch)...

Maintenance Management of Invasions

If eradication fails or is not attempted, it may still be possible to maintain invasive species at low levels and minimize their impacts. Many invasions have been successfully managed in the long-term by a variety of means. These tactics mostly fall in three categories,...

Can We Predict Species Invasions?

Can we predict which species will become invasive if they are introduced? Asa Gray, the great 19th-century American botanist, contended that impacts of invasions cannot be predicted, and invasion biologists from Charles Elton onward have lamented how hard it is to foresee what a...

How and Why Do Invasions Occur?

Why do people deliberately introduce animals? Motives for introducing nonnative species are many. The underlying incentive behind all of these introductions, however, boils down to one simple truth: people are never happy with the species they have. This one phrase could serve as the...

Controversies Surrounding Biological Invasions

Which introduced species are harmful and which are useful? Several critics suggest that rather few introduced species are harmful and some are even useful, so the angst experienced over invasions and the publicity generated about them are overblown. It is true that most introduced...

How Are Species Introductions Regulated?

What international agreements address biological invasions? Most biological invasions arise from the deliberate or accidental transport of species from one nation to another, so it is no surprise that, as the enormous impacts of invasions came to be recognized in the late 1980s (Chapter...

Magnitude, Geography, and Time Course of Invasions

How many introduced species become invasive? To become invasive, a nonnative species must first arrive and establish a population. It is difficult to determine how many species actually arrive, because many of these do not survive or, if they survive, often do not establish...

Evolution of Introduced and Native Species

What is the paradox of invasion genetics? A paradox of invasions is the fact that many widespread invasions began with very few individuals. For instance, the entire North American population of an introduced European solitary bee species probably originated from one female. Additionally, several...

Impacts of Invasions—Complications and Impacts on Humans

What is an indirect effect? Whereas impacts like predation and herbivory are direct effects of an introduced species A affecting a native species B, impacts of invasive introduced species on native species are often mediated in a number of ways by other species, which...