Senegal Small Pelagics Fishery

Abstract

The Senegalese small-scale fisheries on small pelagic fish face challenges in terms of overexploitation of the resource, both by artisanal fisheries and by an industrial, large-scale fishery, as well as increasing effects of climate change. Ecologically, the target species show high resilience to climate change through adult mobility, habitat diversity and ecosystem connectivity. Overexploitation and social and economic changes challenge the fishing communities, but they show resilience through high social diversity, mobility and social capital. However, resilience is constrained by certain socio-economic conditions, including limited wealth and reserves, resilience mindsets, knowledge access, and capacity for technology transfer. In addition, weak governance attributes—particularly effective and efficient, polycentric, and cross-scale governance arrangements—may reduce resilience of these small-scale fisheries.

System Overview

Senegalese small-scale fisheries target two Sardinella species (Sardinella aurita (Round Sardinella) and Sardinella maderensis (Flat or Madeiran Sardinella)), as well as Ethmalosa fimbriata (Bonga Shad). Both Sardinella species perform a migration along the West-African coast, and they are harvested by small-scale fisheries in nearshore coastal waters as well as a small industrial local fleet and industrial foreign vessels (Ter Hofstede & Dickey-Collas, 2006). The fishery on both Sardinella species became important in Senegal with the development of artisanal purse seine fishing in the 1970s, following an FAO project to promote different forms of fishing (Ba et al., 2017). This fishery contributes to both food security and employment, with more than 25% of artisanal fishers (16,000 fishers) targeting these two species and providing about 70% of the consumption of fisheries products in Senegal (Ba et al., 2019).

Catch is dominated by S. aurita. Its share in total purse seine landings is above 80% for all regions but Thiès Sud (57%) (Ba et al., 2017). This fishery is mostly artisanal and open access. The production is mainly used for human consumption locally and more importantly on the regional markets (including landlocked countries like Mali and Burkina-Faso) (Lancker et al., 2019). However, the establishment of fishmeal plants increases the demand and thus increases the fishing pressure and may lead to a reduction in the supply for local markets in the mid- to long-term (Ba et al., 2017).

In general, Senegalese fishers are mobile, both in terms of extending the range of fishing operations as well as migrating either temporarily or permanently along the West-African coast. Senegalese fishers are active in neighboring countries, mainly Mauritania, as the workforce in fisheries is low there and the development of fish meal plants increased the demand in Mauritania (Binet et al., 2012). Mobility of the fleet confers resilience to expand fishing opportunities, which is important given that the possibility of diversification of income is limited depending on the local context. Some communities can include agriculture production as alternative income sources (e.g., Kayar). Others, for example in the Sine Saloum, adapt to changing conditions such as declines in fishing opportunities and the loss of arable land by expanding salt harvest as the main source of income. 

Climate Impacts

The abundance of both species is generally determined by strong seasonal patterns, with S. aurita peaks in spring and autumn and S. maderensis in summer. Interannual fluctuations are linked to the precocity and duration of the upwelling season (Thiaw et al., 2017).

Climate change has an impact on the migration and the general distribution of the species harvested in this fishery. S. aurita is a climate sensitive species. Its abundance has been linked to changes in sea surface temperature (SST). Diankha et al. (2015) find an optimal temperature of 22.7°C, and a generally high abundance between 20°C and 24°C for Senegalese waters. SST in Senegalese waters fluctuates between 18.85 and 28.6°C. Recruitment is linked to upwelling and the availability of zooplankton (Baldé et al., 2019). Fewer studies exist of S. maderensis, but those that are available indicate that it is less sensitive to environmental conditions than S. aurita but also may have less adaptive capacity by virtue of more limited migration (Diankha et al., 2018; Ba et al., 2016).

Climate change is also projected to weaken upwelling, which will reduce productivity of the marine ecosystem off Senegal. In addition, sea level rise is projected to flood low-lying coastal areas, and in some locations, to mobilize nutrients and toxic pollutants in soils. Sea level rise as well as more intense and frequent storms threaten infrastructure that supports fisheries in Senegal (Government of Senegal 2016).

Resilience Attributes and Linkages

Climate resilience in Senegal’s small-scale fisheries for small pelagics is currently supported by adaptive capacities of the target species (e.g., adult mobility, habitat diversity, ecosystem connectivity) and mobility of the fishing fleet. Social capital, which includes bonding, bridging and linking social capital, and social diversity forms the basis for collective action and enables the communities to function effectively. However, though social diversity and social capital are present in the fleet, groups don’t necessarily coordinate together. Resilience to ongoing and increasing impacts of climate change may require building additional socio-economic and governance attributes and prioritizing social diversity and social capital within the fishing community and connecting traditional and new knowledge (Mbaye et al., 2020). Subsidies might amplify climate effects through catch potential increasing with climate change, induced by stock distribution changes (Lancker et al., 2019).

The anticipated climate impacts on this fishery are substantial, yet there is limited funding (i.e., wealth and reserves) for fisheries management and of climate change programming (Government of Senegal 2016). In addition, there is limited scientific and institutional capacity for climate-fisheries modeling and adaptation planning in the region, which constrains knowledge access in decision-making processes (Badjeck et al., 2010). Finally, polycentric and cross-scale governance mechanisms will be needed to address climate issues at national and regional scales (Badjeck et al., 2010).

Conclusion

Climate change is already impacting Senegal’s small-scale fisheries for small pelagics and will continue to do so at an increasing rate. The migratory pattern and productivity of the target species (Sardinella aurita and Sardinella mderensis) are linked to the precocity and duration of the upwelling season, which climate change will weaken. In addition, overexploitation by both small-scale and large-scale fisheries exert extra pressure on the resource. The high mobility of the adult stock as well as habitat diversity and ecosystem connectivity support ecological resilience. By continuing to build the resilience capacity of the existing management regimes and fishing communities the small pelagics fishery will be able to adapt to these impacts. Investment in climate change programming and increasing scientific capacity to monitor climate impacts, at national and regional scales, will be key to overcoming climate-related impacts and increase long-term resilience. In summary, overexploitation and social and economic changes challenge the fishing communities, but they show resilience through high social diversity, mobility, and social capital.