Ecological effects of <i>Spartina anglica</i> on the macro-invertebrate infauna of the mud flats at Bull Island, Dublin Bay, Ireland

Abstract

<i>Spartina anglica</i> (C. E. Hubbard) is a relatively new invasive perennial grass species in Ireland. It is well adapted to the intertidal mudflat environment and forms mono-specific swards. There have been concerns about its potential to impact negatively the ecosystems of mud flats and salt marshes. <br><br> This ongoing project investigates the ecological effects of <i>S. anglica</i>, and its control, on the mudflats and saltmarsh at Bull Island, and the implications for management of <i>S. anglica</i>. The diversity and density of the macro-invertebrate infauna and some physical factors of the sediment were compared in: a) clumps of <i>S. anglica</i>, b) areas vegetated by <i>Salicornia</i> spp., c) an adjacent area of bare mud, and d) an unvegetated area. Presence of <i>S. anglica</i> had a significant effect on the density and diversity of macro-invertebrate infauna species. The results suggest that clumps of <i>S. anglica</i> can provide a habitat that supports a macro-invertebrate infauna as abundant and species rich as areas vegetated by <i>Salicornia</i> spp

Comparing biodiversity effects among ecosystem engineers of contrasting strength: macrofauna diversity in Zostera noltii and Spartina anglica vegetations

“…hypothesis 4) and not as much by a change in sediment properties (refuting hypothesis 1) or feeding type (refuting hypothesis 2). The epibenthos in the vegetated areas was strongly dominated by the small diatom-grazing snail H. ulvae, which was especially clear for Spartina, and in accordance with previous observations (for seagrasses, see Bostrom and Bonsdorff 1997;Bachelet et al 2000;Blanchet et al 2004;Cottet et al 2007; for salt marsh plants see Kneib 1984;Mc Corry and Otte 2000;Whaley and Minello 2002;Cottet et al 2007). It is not clear to which extend this increase is due to enhanced food availability (cf.…”