ABSTRACT

MORTEN F. PEDERSEN6, FRANCISCO ARENAS7, CONSOLACIÓN FERNÁNDEZ8, HENNING STEEN9, ROBIN SVENSON10, HENRIK PAVIA10, GUNILLA TOTH10,

FRÉDÉRIQUE VIARD11,12 & RUI SANTOS1

1Center for Marine Sciences (CCMAR), University of Algarve, FCMA, Campus de Gambelas, 8005-139 Faro, Portugal

E-mail: aengelen@ualg.pt (corresponding author) 2Marine Science Laboratory, School of Life Sciences,

The Chinese University of Hong Kong, Shatin, N.T., HKSAR, China 3Friday Harbor Laboratories, University of Washington,

620 University Road, Friday Harbor, Washington 98250, USA 4School of Biological Sciences, Queen’s University Belfast,

Medical Biology Centre, 97 Lisburn Road, Belfast, BT9 7BL, UK 5Institute for Global Food Security, Queen’s University Belfast,

18-30 Malone Road, Belfast, BT9 5BN, UK 6Roskilde University, Department of Environmental, Social and Spatial Change,

11-2, Universitetsvej 1, P.O. Box 260, DK-4000 Roskilde, Denmark 7CIIMAR, University of Porto, R dos Bragas 289, 4050-123 Porto, Portugal

8Departamento de Biología de Organismos y Sistemas, Universidad de Oviedo, c/ Catedrático Rodrigo Uría s/ n. E-33071 Oviedo, Spain

9Institute of Marine Research in Norway, Research Group of Benthic Habitats and Shellfish, Norway

10Department of Biological and Environmental Sciences, University of Gothenburg, Tjärnö Marine Biological Laboratory, 452 96 Strömstad, Sweden

11Sorbonne Universités, UPMC Univ Paris 06, UMR 7144, Station Biologique de Roscoff, 29680 Roscoff, France

12CNRS, UMR 7144, Divco Team, Station Biologique de Roscoff, 29680 Roscoff, France

Hundreds of macroalgal species have been spread outside their natural range by human activities, and many of these introductions are occurring at a worldwide scale. This review considers one of the best-studied and most widespread invasive macroalgae, Sargassum muticum, to determine the traits and processes important in marine invasions and to identify important lines of future research. Particular emphasis is placed on the ecology of S. muticum in its native range and on the four stages of invasion-transport, colonization, establishment, and spread-integrating taxonomy, invasion history, dispersal, impact, invasiveness and invasibility, and general ecology. Although S. muticum has received a lot of scientic attention, with more than 650 papers on this species, key information on its taxonomy, invasive biology, and evolutionary potential is still lacking. Most previous studies have been local or descriptive or provide circumstantial evidence, and too few have been hypothesis driven. Only by local-scale research conducted in different geographical regions, especially including the

native range, and developed in an eco-evolutionary framework, will it be possible to greatly improve our understanding of the complex of factors, traits, and processes involved in macroalgal invasions.