Occurrence Of Cetaceans Along The Cameroonian Atlantic Coast And The Importance Of Environmental Variables Of Oceanic Aquatic Resources

Abstract

Biodiversity conservation thus addresses a growing global imperative, given the numerous challenges it faces. This ambition extends far beyond the mere protection of threatened species—such as cetaceans—which is already partially covered by various international conventions. Threats to marine and coastal ecosystems are primarily direct, stemming from industrial fishing, intensive aquaculture, the intentional or accidental introduction of invasive species, aggregate extraction, coastal tourism, and environmental modification (such as embankments). They are also indirect, resulting from various human activities that generate pollutants (heavy metals, organic matter, nutrients, herbicides, and fungicides) transported via diverse discharges and river systems. The study area (Figure 1) is located in the Gulf of Guinea, in southern Cameroon, encompassing the localities of Nlende Dibe (N02°46’42.9’’, E009°52’56.9’’; elev. -4m), Mboro (N02°43'50.4’’, E009°52’17.4’’; elev. 3m), and Lolabe (N02°41'39.2’’, E009°51’32.1’’; elev. -5m). Key study methods include visual observation and photo-identification: scientists use photographs of dorsal fins or tails (flukes)—featuring unique patterns, scars, and nicks—to identify, census, and track individuals and populations over the long term. Cetacean sightings occur at a rate of 1 to 2 per month, covering both mysticetes and odontocetes. Variations in physicochemical parameters (CO2, O2, pH, temperature, suspended solids, salinity) during the study period indicate a deterioration in water quality.