Oceanic habitats reach from the shoreline to the deep sea and include both pelagic and benthic habitats. Surface marine waters in the tropics are generally depleted in nutrients but in certain coastal regions, the nutrients are locally enhanced as a result of upwelling. The Sierra Leone coast as part of the Guinea Current coast is characterized by such an upwelling which is seasonal and occurs from Cape Palmas to Benin Republic.

Habitat quality assessment

The shallow coastal waters of the Sierra Leone have a highly diverse fish and invertebrate fauna, many of which are important in commercial fishing. Fish diversity in the coastal waters is reasonably well documented (FAO 1990). What is poorly known is the diversity of the benthic macro-fauna i.e. animals that live on the bottom or within the bottom sediment and can be retained on a 0.5 mm sieve. The situation is much worse for the meiofauna i.e. organisms smaller than 0.5 mm. Sub-tidal benthic habitats are among the least studied in the waters of the Sierra Leone Continental shelf. According to the assessment resulting from the workshop held in Freetown in February 2014, thirteen habitats were assessed (Fig. 4.1).