Molluscan assemblages on coral reefs and associated hard substrata in the northern red sea

Author(s)
Martin Zuschin, Johann Hohenegger, Fritz F. Steininger
Abstract

Information on spatial variability and distribution patterns of organisms in coral reef environments is necessary to evaluate the increasing anthropogenic disturbance of marine environments (Richmond 1993; Wilkinson 1993; Dayton 1994). Therefore different types of subtidal, reef-associated hard substrata (reef flats, reef slopes, coral carpets, coral patches, rock grounds), each with different coral associations, were investigated to determine the distribution pattern of molluscs and their life habits (feeding strategies and substrate relations). The molluscs were strongly dominated by taxa with distinct relations to corals, and five assemblages were differentiated. The Dendropoma maxima assemblage on reef flats is a discrete entity, strongly dominated by this encrusting and suspension-feeding gastropod. All other assemblages are arranged along a substrate gradient of changing coral associations and potential molluscan habitats. The Coralliophila neritoidea-Barbatia foliata assemblage depends on the presence of Porites and shows a dominance of gastropods feeding on corals and of bivalves associated with living corals. The Chamoidea-Cerithium spp. assemblage on rock grounds is strongly dominated by encrusting bivalves. The Drupella cornus-Pteriidae assemblage occurs on Millepora-Acropora reef slopes and is strongly dominated by bivalves associated with living corals. The Barbatia setigera-Ctenoides annulata assemblage includes a broad variety of taxa, molluscan life habits and bottom types, but occurs mainly on faviid carpets and is transitional among the other three assemblages. A predicted degradation of coral coverage to rock bottoms due to increasing eutrophication and physical damage in the study area (Riegl and Piller 2000) will result in a loss of coral-associated molluscs in favor of bivalve crevice dwellers in dead coral heads and of encrusters on dead hard substrata.

Organisation(s)
Department of Palaeontology
External organisation(s)
Senckenberg Biodiversity and Climate Research Centre
Journal
Coral Reefs
Volume
20
Pages
107-116
No. of pages
10
ISSN
0722-4028
Publication date
2001
Peer reviewed
Yes
Austrian Fields of Science 2012
105118 Palaeontology
Sustainable Development Goals
SDG 14 - Life Below Water
Portal url
https://ucrisportal.univie.ac.at/en/publications/molluscan-assemblages-on-coral-reefs-and-associated-hard-substrata-in-the-northern-red-sea(21106b00-1538-465b-856a-fa04461b8afc).html