Ecological and evolutionary consequences of coastal invasions

Although coastal estuarine and marine systems are among the most heavily invaded systems in the world, the study of nonindigenous species in these systems has, historically, lagged behind that of terrestrial and freshwater systems. However, in the past decade, a rapid increase in studies of coastal invasions has provided important insight into the invasion process in these systems and how these invasions might differ qualitatively from invasions elsewhere. Based on new evidence for cryptic species invasions, hybridization among invaders and native species, impacts on multiple species and ecosystems, and the rapid and extensive geographical spread of invaders, it is clear that the ecological and evolutionary consequences of invasions in heavily invaded coastal habitats might be more extensive than previously realized. Although these studies have produced important new advances, many other areas remain relatively unexplored and are ripe for future investigation.