Biological Invasions

Biological invasions are a major force of change, affecting many dimensions of life on Earth.  Invasions result when species colonize new geographic regions, which are disjunct (isolated) from existing populations.  Invasion dynamics have been altered dramatically by humans and especially the global expansion of trade in modern time.

Historically, geographic barriers such as oceans and continents have shaped the dispersal, distribution, and evolution of organisms throughout life’s history.  These types of major dispersal barriers were sometimes breached by shifting land masses and sea level over geologic time as well as episodic or rare events, such as storm- and tsunami-induced rafting or aerial dispersal of organisms.  In recent time, human activities increasingly transfer organisms across these barriers, altering the magnitude and tempo of dispersal and the types (diversity) of organisms moved around the world.

Today, new invasions are dominated by human-aided dispersal, where species are moved across continents and ocean basins in hours to days by global trade.  Transportation and the movement of organisms by humans – both intentional and unintentional -- has greatly accelerated the baseline rate of invasions for marine, freshwater, and terrestrial habitats throughout the world, allowing many species transfers that would never occur otherwise.  From the poles to the equator, no global region is immune to human-mediated invasions, which are strongly affecting population-to-ecosystem level processes, disease dynamics, and goods and services to society.  

SERC is a world leader in research on biological invasions with diverse research programs that explore (a) the underlying mechanisms that lead to invasions, (b) changing spatial and temporal patterns of non-native species occurrence, (c) the ecological, social, and conservation consequences of invasions, and (d) the effects of management and policy on invasion dynamics and impacts.  As a cross-cutting theme that affects many ecological processes, SERC invasion research is conducted across marine, freshwater, and terrestrial habitats at the population, community, and ecosystem level.