Pioneer species are resilient species that are the first to colonize barren environments, or to repopulate disrupted biodiverse steady-state ecosystems as part of ecological succession. A number of kinds of events can create good conditions for pioneers, including disruption by natural disasters, such as wildfire, flood, mudslide, lava flow or a climate-related extinction event or by anthropogenic habitat destruction, such as through land clearance for agriculture or construction or industrial damage. Pioneer species play an important role in creating soil in primary succession, and stabilizing soil and nutrients in secondary succession.
Pioneer species of plant growing in cracks on a solidified recently erupted lava flow in Hawaii
Pioneer plants growing on solidified lava on Pico, Azores, avoiding local laurisilva competition
Centaurea maculosa, an example of pioneer species
Colonisation or colonization is the spread and development of an organism in a new area or habitat. Colonization comprises the physical arrival of a species in a new area, but also its successful establishment within the local community. In ecology, it is represented by the symbol λ to denote the long-term intrinsic growth rate of a population.
The range of the little egret (Egretta garzetta) has expanded since the 20th century, with the species having colonised most of the New World.
Image of the green Iguana that colonized Anguilla.
