The marine environment off Berbera is very productive. Seaweeds flourish in many areas in the inshore region and wind-generated water movement promotes their growth as well as the transport and breakdown of algal detritus in the system. Large shoals of fish were observed in the region and these provide food for numerous dolphins, a further indication of high productivity. The seaweed beds, associated detritus and climatic energy subsidy make a contribution towards the productivity of the area. Further study would be needed to establish the importance of seaweed production relative to that derived from upwelling.
The coastline is relatively straight and consists mainly of beaches; very small rocky promontories occur only in a few localities. A raised fossilised seabed backs many of the beaches. The dunes behind the beaches are generally low and sparsely colonised by xerophytic grasses and shrubs, as is the coastal plain. A high dune field, which is almost devoid of vegetation, occurs in one locality and arid rocky mountains are found at three sites.
At the time of the study, the beaches had a clear monsoon storm berm above the present high water mark. The latter was littered with seaweed, some coral fragments and large numbers of shells, particularly shells of gastropods occupied by scavenging hermit crabs. Remarkably little pollution was found. Ghost crabs were prolific on some beaches.
The subtidal sandy substratum appears to be relatively sterile. Seaweed detritus had accumulated in the sand ripples in certain areas and a single concentration of holothurians was found next to one reef. However, very few observations were made on the sand substratum because of time constraints and this environment may be inhabited by burrowing organisms such as bivalves. No evidence of their presence was found in beach litter.
As stated, rocky shores were sparse. The intertidal zone had a clear band of Saccostrea cucullata, some whelks (Nerita sp.) and grapsid crabs. No corals were observed in the subtidal region, which was also sparsely vegetated with few algae, probably because of surf energy. Reefs were found between 1-10 m and appeared to originate from fossilised beach rock. They thus appear to represent a submerged coastline and were patchy.
The coral communities on the reefs varied considerably in their condition. All had been affected by bleaching to some degree. The shallow reefs (1-2 m) to the west of Berbera were slightly bleached and those <1 m appeared to have died from tidal exposure. The shallow reefs to the east of Berbera were far more severely affected by bleaching and, in many instances, had suffered nearly total mortality and become both encrusted and accreted by coralline algae. Montipora stellata had commenced recolonisation of these areas.
Deeper reefs (2-5 m) were in better condition. Patchy reefs subject to considerable sedimentation were dominated by sediment tolerant faviids, while more established reefs were dominated by Porites spp. and plate Montipora spp. Astreopora myriophthalma was conspicuous on the deepest reefs (5-10 m) and manifested recovery from crown-of-thorns (COTS) predation. Three COTS were found on one reef. A total of 69 species of scleractinian coral, 11 species of alcyonacean (soft) coral and two species of fire coral were found during the survey. Other reef organisms encountered during the field work were sparse and included only five Panulirus versicolor, two specimens of two species of anemones, five specimens of Tridacna spp. and various sponges, ascidians, holothurians, echinoids, crinoids, molluscs and zoanthids.
Seaweed were widespread in patches on hard substrata, both in the inshore area and in deeper water (<10 m) that is sedimented to a varying degree. Their prevalence on substrata which would otherwise appear more suitable for corals is probably due to a combination of physico-chemical factors. These would include the levels of turbidity and sedimentation that were observed, as well as the nutrient enrichment emanating from these factors and regional upwelling. A range of green, brown and red algae were recorded. Sheets of Zoanthus sansibaricus and a number of sponges were associated with the deeper algal beds.
Reef fish were diverse and the presence of large schools of fish as well as an abundance of large fishes indicated a relatively unexploited resource and pristine environment. The diversity of reef fish was greatest in the coral reef environment and substantially lower in areas with a rocky or sandy substratum and in algal dominated assemblages. However, the abundance of fishes, including juveniles, in the latter environment was higher. The reef fish community differs considerably from that of the eastern Arabian Peninsula to the north, and the fish communities of eastern Africa to the south and the Red Sea to the west.
Large shoals of pelagic fish were conspicuous. Pelagic fishes observed at sea included schooling tuna (e.g. bonito), carcharinid sharks and whale sharks.
Small cetaceans are abundant in waters off Somaliland. A total of 35 sightings of five species of dolphins (common, spinner, spotted, bottle-nose and humpback dolphins) were recorded during the survey. More than 20 species of sea and shore birds were recorded but, in the case of gulls and terns, these were not as numerous as anticipated, particularly as feeding aggregations over shoaling fishes.
Evidence of turtle nesting was found on beaches distant from Berbera. A total of 36 nests was the highest density encountered along a five km stretch of coast. Turtle remains and sightings at sea suggested that green turtles and hawksbill turtles are the commonest species in the area, while a single loggerhead turtle was seen at sea. The major threat to turtles arises from the opportunistic harvest of green turtles which includes incidental gill net entrapment. Natural threats to the eggs include the flooding of nests and the likelihood of egg consumption by land mammals. Humans apparently collect turtle eggs during the Southwest Monsoon season.
The extensive lagoon at Khoor Shoora is bounded by a fringe of Avicennia marina. It is characterised by clean sediment, clear water and prolific seaweed growth; there appeared to be little freshwater input. Little evidence of timber extraction was found and very little appears to be used as firewood. The fauna in the area included a number of birds, abundant juvenile fishes and mud crabs.
Marine resources are used only on a small scale in the study area, canoes being used to set a limited number of 7, 15 and 30 cm stretch mesh size gill nets. Handline fishing was observed on one occasion. Sharks are especially targeted in these operations with only the valuable fins being landed; this is largely due to a lack of refrigeration.
Turtles appear to be harvested opportunistically, both by jigging and harpooning at sea and through the capture of nesting turtles. Both fishermen and nomadic herdsmen are probably responsible for the latter; herders have temporary shelters and animal pens on certain beaches. - Source