English version - Convention on Biological Diversity

• Oil exploration (in the future);
• Sedimentation from land reclamation;
• Population increase;
• Destructive fishing activities (trawling in Shallow waters)
• Solid waste disposal and sewage from septic tanks;
• Occassional oil spills
• Effluents from desalination plants
• Dust from industrial activities (cement)
• Curios collections (shells,corals)
• Climate change
In addition corals are also threatened by natural factors such as crown of thorns (starfish),
sea urchins or drupella infestation, or from human induced impacts such as bleacing
related to global climate change; massive bleaching observed in the Nora islands in the
1998 global warming.
Figure-4: Diverse species of stony and soft Corals in the the Dahlak Archipelago (Source: ECMIB Project)
Sea Grasses and Sea Weeds:
As part of the overall marine Biodiversity inventory, ECMIB’s surveys were also inclusive
for sea grass biodiversity. Out of the 60 species existing worldwide the 10 are present in
the Eritrean waters: Thalassia hemprichii, Halophila ovalis, Halophila stipulacea, Enhalus
acoroides, Cymodocea rotundata, Halodule uninervis, Syringodium isoetifolium, and
Thalassodendron ciliatum and other unidentified species. The Southern Eritrean marine
zone is characterized by more extensive soft bottomed continental shelves and higher rate
of water influx from the Indian Ocean as compared to the Central region. These combined
with other physico-chemical and ecological factors results in increasing sea grass
abundance southwards. Due to limitations in survey methodologies however (confined
only to sub-tidal and inter-tidal zones), their vertical distributions is not well known.
Sea weeds on the other hand also constitute important part the diversified Eritrea’s coastal
marine and Island Biodiversity elements. In most of the assessments carried out sofar all
the three major groups of Thallophyta are well represented along the Eritrean coastline.
Out of the the 26 common sea weed species identified, 9 are Chlorophyta (Green algae),
12 Phaeophyta (Brown algae) and 9 Rhodophyta (Red algae). Spatial distribution is not
uniform. Sorgassum and Turbinaria are the most dominat in the southern part of
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