Fish populations along the coast of West Africa have experienced a notable decrease over the last fifty years, jeopardizing food security and the livelihoods of communities reliant on fishing, according to a recent study.
Fish populations along the West African coast have undergone a drastic reduction over the last fifty years, posing risks to food security and the sustenance of fishing communities that rely on these resources, as highlighted by research from the Institute of Environmental Science and Technology at the Universitat Autònoma de Barcelona (ICTA-UAB) in partnership with Fundação Maio Biodiversidade (FMB).
Small-scale fisheries are crucial for feeding and supporting millions globally, especially in the low-income regions of Africa. However, comprehensive data regarding the types, quantities, and distributions of fish resources remains scarce, which is essential for proper management.
A new study published in the journal Marine Policy reveals significant declines in the catches of small-scale fisheries, not just in the volume of fish caught but also in the sizes of fish for key species within local markets.
Researchers gathered official catch data and integrated it with insights from local fishermen and fish sellers on Maio island in Cabo Verde, which has been recognized as a UNESCO Biosphere Reserve since 2020.
Thais Peixoto Macedo, a researcher at ICTA-UAB and the study’s lead author, explains, “Monitoring fish landings in West African nations is inadequate and fails to accurately reflect local catches, particularly from artisanal fisheries, which results in significant data gaps that obstruct effective management.” She adds that traditional fishers’ observations pointed out trends that are frequently overlooked in official data. “The insights gained here are likely indicative of trends observable on other islands in the archipelago or throughout West African coastal regions and should be incorporated into marine resource management strategies.”
Local communities indicate that specific fishing methods, including scuba spearfishing and semi-industrial fishing practices utilizing purse seines and night lights, are contributing significantly to the decrease in fish populations. They also report instances where semi-industrial vessels operate within the three-nautical-mile zone and in zones designated for artisanal fishing.
Among the species most significantly impacted are groupers (dusky grouper, island grouper, and African hind) as well as small pelagic fish such as mackerel and bigeye scad. “Local fishermen assert that the overfishing of small pelagic fish by semi-industrial operations is adversely affecting their catches of larger pelagic species, such as yellowfin tuna and albacore, which are vital for both local and global markets,” explains Benalsy Varela from FMB, who assisted in the study. Decreases have also been noted in spiny and slipper lobsters, especially those targeted to meet the demands of high-tourism islands.
The study brings attention to a phenomenon referred to as “Shifting Baseline Syndrome,” where people’s perceptions regarding what constitutes a healthy ecosystem change gradually to align with a new norm, causing them to forget previous conditions. Younger fishermen report fewer catches and smaller fish compared to older generations; nevertheless, a significant portion of the younger demographic does not believe that fish stocks are declining.
