Which traits confer invasibility to a species?

DIANA MARCO

Granada

Congreso; III Spanish National Meeting on Biodiversity; 2011

Estación Experimental del Zaidín-CSIC

  Biological invasions are one of the most important threats to biodiversity, with serious ecological and economic consequences. Two main aspects are involved in the invasion : the traits  enabling a species to invade a habitat (invasiveness,) and the habitat characteristics that determine its susceptibility to invasion (invasibility). Other main aspect of biological invasions linking invasiveness and invasibility are the complex interaction emerging among the invader species, the native species present in the habitat, and the habitat Itself. Modelling is a suitable approach for studying and predicting biological invasions. The main elements of the biological invasion process are organised, considering model inputs (species and habitat information) and outputs (predicted patterns, and rates of invasion) giving a better understanding of invasiveness. Integrating species´ traits [longevity, fecundity, age at reproduction, dispersal (short or long distance), propagule bank] and habitat suitability in a spatially explicit, cellular automaton model  predicted invasion patterns  that matched closely the field data. In addition, traits conferring invasiveness were determined and better understood, like the role of long distance dispersal in pattern formation. Not yet described relationships between invasiveness and habitat invasibility were also found. Modelling allowed to determine traits conferring invasiveness: invader’s propagule bank, adult survival, dispersal distance and age of reproductive maturity. In contrast, fecundity was not relevant as previously thought. Among other interactions found, longevity of the native species and habitat suitability influenced the spread velocity of the invader.