research projects | biodiversity | meiobenthos | coral ecology | fish ecology | fossil reefs | behavior
     
 
 

Biodiversity of Marine Sponges from the Red Sea

Sponges are a diverse group of ancestral metazoans with a relatively primitive body plan, with a world-wide diversity of more than 15,000 species. They inhabit most marine and freshwater habitats and are highly effective filter feeders that produce very potent bioactive compounds. Some of them play also a very important role in bioerosion, i.e. boring sponges such as Cliona spp. that etch out and bore into living and dead coral. However, biodiversity of this key-group in the Red Sea is relatively unexplored, with only few studies especially dealing with biodiversity assessment (Lévi, 1965; Row, 1911; Sarà et al., 1979).

 

Leucetta chagosensis

 
 

Biodiversity and Biogeography of Red Sea Holothurians

Holothurians are a diverse group of echinoderms with a highly evolved body plan, with a recent world-wide diversity of more than 1,450 species. They inhabit all marine habitats from the shallow water to the deep-sea and are ecologically important, e. g. as bioturbators of the sediment. Some of them play also a very important role in commercial bêche-de-mer fisheries (e. g. Lawrence et al. 2004). However, biodiversity of this keygroup in the Red Sea is relatively unexplored, with only few studies dealing with taxonomy (e.g. James & Pearse 1970).

 

Holothuria

 

 
 

Biodiversity of the Dahab Marine Environment - Generation of Basic Information on Marine Flora and Fauna as well as Ecological Structures

First inventory of shallow water species on the fringing reef of Dahab

Objectives of the study
1. Identify marine key habitats in the vicinity of the RSEC field station in Dahab, with emphasis on the reef flat. In particular, the focus will be on shallow water algal communities, patchy reef components, sea grass beds and gravel bottoms.
2. Map and characterize the typical habitats through line transects (perpendicular to shoreline) and quadrates, with description of community structures and elaboration of depth profiles.
3. Classify and identify (as far as possible) marine plants and invertebrates and determine distribution, abundance and dominance of selected species.
4. Document each species through scanning images and digital photography wherever possible, and preserve reference specimens.
5. Archive all images and information in a local scientific data base and reference collection at the RSEC in Dahab (as an information and documentation centre).

  Dictyota canaliculata

Elamena mathei

 
 

Biodiversity and Biogeography of Red Sea Scleractinians

Generally most scleractinian species show a certain variation, environmental and regional, which made the identification quite difficult. Veron (2000) ascribes to this fact the certainty with which a local taxonomist is able to identify a particular coral species decreases gradually with distance from the region he works. The difficulty of assessing the extent of hybridisation between coral species and the influence of a possible reticulate evolution (hypothesis) are further obstacles to coral identification. The references regarding distribution and species number for the Red Sea in the literature (Sheppard & Sheppard 1991, Wallace 1999, Veron 2000) differ to some extent, especially in the genus Acropora. Wallace (1999) gives 43 species compared to 52 of Veron (2000). Veron (2000) excludes 5 of the species given by Wallace (1999) from the Red Sea and in addition assesses 6 more as uncertain. In return he gives species unidentified by Wallace (1999) Acropora anthocercis). In addition, 15 species are stated as uncertain for the Red Sea by Veron (2000).

 

 

 

Trachyphyllia geoffroyi

Acropora Assemblage