Effects of macroepifauna on developing nematode and harpacticoid assemblages in a subtidal muddy habitat

• Published in: Marine ecology. Progress series (Halstenbek) Vol. 84; no. 2; pp. 161 - 171
• Main Authors: Ólafsson, Emil, Moore, Colin G.
• Format: Journal Article
• Language: English
• Published: Inter-Research 1992
• Subjects: Animal communities; Aquatic communities; Community structure; Ecological competition; Fauna; Longipedia helgolandica; Marine; Nematoda; Nematodes; Predators; Sediments; Species; Species diversity
• ISSN: 0171-8630; 1616-1599
• DOI: 10.3354/meps084161

In order to assess the effects of macrofauna on meiofaunal community structure, field investigations were performed in a low energy subtidal muddy sediment in Loch Creran, a sea-loch on the west coast of Scotland. Meiofaunal colonization of azoic sediment was studied in cages designed to exclude macrofauna to varying degrees. In all the cages high diversity assemblages developed rapidly. Considerable variation in species composition was found, both for nematodes and harpacticoids, and no indication that exclusion of the macrofauna was influencing the early colonizing individuals. For the harpacticoid species the results from multivariate analyses indicated a strong successional pattern inside the cages. However such a pattern was not obvious for the nematode component of the meiofauna. The semi-pelagic harpacticoid copepod Longipedia helgolandica became extremely abundant inside the cages, while it was hardly found in the background sediment. The initial colonization by most of the harpacticoids was marked by a high proportion of copepodites. The exclusion of macroepifauna did not result in a simpler meiofaunal community as one would expect if suppression of dominant competitive relationships by macroepifauna occurred. This study emphasizes the complexity of the community organization, where multitrophic relationships may be of vital importance as factors influencing community structure.