Macro- and mesoherbivores prefer native seaweeds over the invasive brown seaweed Sargassum muticum: a potential regulating role on invasions

• Published in: Marine biology Vol. 156; no. 12; pp. 2505 - 2515
• Main Authors: Monteiro, Carla A, Engelen, Aschwin H, Santos, Rui O. P
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Berlin/Heidelberg : Springer-Verlag 01.11.2009; Springer Berlin Heidelberg; Springer; Springer Nature B.V
• Subjects: Algae; Animal and plant ecology; Animal, plant and microbial ecology; Biological and medical sciences; Community structure; Competition; Competitive advantage; Freshwater & Marine Ecology; Fundamental and applied biological sciences. Psychology; Growth rate; Herbivores; Herbivory; Introduced species; Life Sciences; Marine & Freshwater Sciences; Marine biology; Microbiology; Native species; Oceanography; Original Paper; Sea water ecosystems; Studies; Success; Synecology; Tissues; Zoology; Portuguese Coast; Brown Seaweed; Enemy Release Hypothesis; Relative Growth Rate; Seaweed Species; Algae; Native species; Invasion
• ISSN: 0025-3162; 1432-1793
• DOI: 10.1007/s00227-009-1275-1

Herbivory has a strong impact on algal distribution, abundance and community structure and may influence the establishment and spread of introduced seaweed species. In this study, we assess the potential regulating role of herbivory on one of the most invasive brown seaweeds: Sargassum muticum. Multiple choice feeding experiments were conducted with 13 native seaweeds, S. muticum and 5 herbivore species from the Northwest, Southwest and South of Portugal. S. muticum was always the least or among the least preferred seaweeds and attained one of the highest growth rates of the tested seaweeds, with and without herbivores. The addition of herbivores increased the number of cases by 40% in which the invader had higher growth rates. Our results suggest that low grazing pressure on S. muticum by the recipient herbivore community may give the invader a competitive advantage over at least part of the native seaweed community, thereby contributing to the invasiveness of S. muticum along the Portuguese coast.