Meiofaunal Diversity on Invasive Sargassum muticum Versus Native Seaweeds

Abstract

The meiofaunal assemblage on the invasive brown alga, Sargassum muticum, was compared to that on three native algal species. I predicted that differences in the meiofaunal diversity, abundance, and community composition would be influenced by the morphological complexity and palatability of an alga. I found that the algal structural palatability, rather than chemical palatability, was a factor in the preferences of one genus of meiofauna (Lacuna sp.). The results also suggest that the level of structural complexity of an alga determines its relative abundance of meiofauna, while the type of structural complexity determines its meiofaunal community composition. Even though Sargassum did not support a lower diversity of meiofauna compared to each individual native species, a monoculture of Sargassum would support a less diverse community of meiofauna compared to a diverse community of native seaweeds.