The coastal zone of Cameroon, once a vibrant ecosystem teeming with life, is now faces a silent and growing threat: a dead zone. Dead zones are hypoxic areas of the ocean, in other words areas where the concentration of oxygen is below the norm: there can be a drop of up to 20% of the usual oxygen, which is already significant, and it can be as much as 50% below normal levels. This phenomenon, characterised by oxygen-depleted waters causes a change in the environment, and this of course has an impact on marine biodiversity in the sense that when there is less oxygen, the fish, which need it to breathe, find themselves in a hypoxic situation, and risk dying (Tristan B, 2024) and also posing a significant challenge to the country’s coastal communities.
The causes of Cameroon’s Dead Zone
The primary culprit behind the dead zone is nutrient pollution, principally from industrial effluents which contain untreated industrial wastewater containing organic matter and nutrients discharged into rivers and the sea (M.Sc. Dissertation, 1999),followed by agricultural runoff and untreated sewage. Likewise, studies in the Mount Cameroon coastal region have documented noxious blooms of Cyanophyceae (blue-green algae) linked to high nutrient concentrations, particularly nitrates (Research Gate, 2011). According to MSP-global, 2019, the coastal zone of Cameroon is home to nearly 60% of the national industrial complexes and high urbanisation rates and population growth can increase the discharge of domestic and industrial waste.
These pollutants, rich in nitrogen and phosphorus, fuel the growth of algae blooms which are a precursor to oxygen depletion. When these blooms die and decompose, they consume oxygen from the water, creating hypoxic conditions that suffocate marine life. Although, widespread Dead zones might not be widely reported due to lack of extensive and specific scientific studies focused on measuring the dissolved oxygen levels and identifying large-scale hypoxic zones along the entire Cameroonian coast, the presence of nutrient pollution, algal blooms and industrials/urban discharge suggests or indicates that localised hypoxic events are possible and that the conditions for the development of dead zone may exist in certain areas in Cameroon’s coastal waters.
The impact on Marine Life
The dead zone has had a devastating impact on Cameroon’s coastal ecosystem. Fish kills have become increasingly common, with thousands of fish suffocating and washing ashore. The loss of marine life not only disrupts the food chain but also threatens the livelihoods of coastal communities that rely on fishing for sustenance and income.
Effort to combat the Dead Zone
Although there are conventions on the protection of the oceans signed and ratified by Cameroon and several countries around the world, the Cameroonian government, in collaboration with environmental organisations and local communities, should put in more efforts to combat the dead zone. These effort include;
- Reducing nutrient pollution: implementing stricter regulations on agricultural practices and improving wastewater treatment infrastructure.
- Promoting sustainable fishing practices: implementing fishing quotas and gear restrictions to reduce the pressure on fish populations.
- Raising public awareness: education coastal communities about the importance of protecting the marine environment and promoting sustainable practices
A call for Action
While these efforts are underway, more needs to be done to address the growing threat of the dead zones. Increases investment in research and monitoring is crucial to better understand the dynamics of the dead zone and develop effective mitigation strategies. Additionally, regional cooperation is essential to address the transboundary nature of nutrient pollution.
For the well-being and preservation of these oceans, every consumer can play a part in safeguarding marine life by choosing to buy products from organic farming, for example, more environmentally-friendly cleaning products or biodegradable materials, and by limiting the discharge of agricultural products into the ocean.
Calixte Bikié