The austral cordgrass Spartina densiflora Brong.: its taxonomy, biogeography and natural history

Aim During the last 20 years, the austral cordgrass Spartina densiflora has been recorded aggressively invading estuarine environments in the USA, Spain and Morocco. Whereas this species is one of the three most widely distributed worldwide, it is among the least studied within the genus. The objective of this work is to integrate baseline information about the taxonomy, global distribution, centre of origin, and general ecology of S. densiflora in native and invaded marshes worldwide in order to help to strengthen management efforts currently directed at controlling or eradicating it from locations where it has been introduced. Location World-wide. Methods I review, update and discuss relevant information about S. densiflora published in peer-reviewed papers, including those in journals with limited international distribution. I also review theses and major technical reports containing critical up-to-date information. Results This work indicates that, although S. densiflora remains in need of thorough scientific attention, key information on its taxonomy, distribution and invasive biology has been overlooked because it was published in languages other than English, and/or in journals with restricted distribution. Main conclusions Spartina densiflora seems to have originated along the east coast of South America; today, however, many other regions worldwide serve as donors for this invasive species, including Chile, the USA, Spain and Morocco. Spartina densiflora is a bioengineer organism, tolerant of a broad spectrum of environmental conditions and able to re-shape the structure of invaded communities not just in mudflats, but also on sandy, muddy, and rocky shores as well as on cobble beaches. Only by integrating local-scale research conducted in different geographical regions will we be able to understand the between-site variations of its biological cycle, which in turn will aid in the design of more effective conservation strategies.