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The fisheries for small pelagic species in Angola, Namibia and South Africa fulfil important social and economic roles but have undergone substantial changes in recent years, some of which are likely to be related to climate change. This assessment of vulnerability and possible adaptation options for the main stakeholder groups in these fisheries was based on a framework encompassing ecological, social and economic vulnerability and the broader economic and governance context of the countries. Information was gathered through stakeholder consultations and workshops as well as from published information. Adaptation options were identified primarily through consultation with stakeholders. Namibia was considered to have the most vulnerable fishery because of the poor state of the sardine population and limited alternatives. Angola and South Africa were estimated to be moderately vulnerable for different reasons. Alternative sources of livelihoods are scarce, and the wellbeing of stakeholders is highly dependent on the resilience and adaptive capacity of individual fishing companies. For land-based and sea-going workers (fulltime and permanent), skills improvement to increase their flexibility and employability within and beyond fisheries is a primary adaptation option. Key roles for governments include ensuring effective governance and facilitating sustainable economic development, especially in underdeveloped coastal areas. [ABSTRACT FROM AUTHOR]

The Frenchman seabream Polysteganus baissaci is an important commercial fish species found on the slopes of the fishing banks of the exclusive economic zone of Mauritius. Exploitation of this species started in 2007, and it is targeted using hydraulic reels with baited hooks. The introduction of suitable management measures is important for this fishery and a sound understanding of the biology is required. Monthly biological data were collected over a 2-year period from fish landed in the commercial catch, to investigate aspects of the biology. A total of 698 females and 1 129 males (sex ratio 1:1.6) were collected from commercial fishing vessels operating on the Nazareth Bank. Females dominated smaller size classes (30–36 cm total length [TL]), whereas males were mostly present at larger sizes (37–44 cm TL). Although ripe and spent female gonads were found throughout the study period, the gonadosomatic index (GSI) revealed a peak in spawning between April and September, coinciding with the cooler sea temperatures in the region. Male GSI (0.169 [SD 0.0443]) during its peak month (August) was more than 14-times lower than the female GSI (2.470 [SD 1.0185]) during its peak month (July), and this, together with male and female length frequencies and adult sex ratios, provides strong supporting evidence for protogyny in this species. Although this fishery appears to harvest adults exclusively, which is positive in terms of sustainability, the potential hermaphroditism in this species necessitates implementation of a conservative harvest strategy, including effort limitation and a closed fishing season over the peak spawning period. [ABSTRACT FROM AUTHOR]

The stock status of roman Chrysoblephus laticeps was estimated in the Goukamma, a temperate South African marine protected area (MPA). Standardised catch per unit effort (CPUE) from a controlled angling survey on both sides of the MPA border was employed to extrapolate the CPUE at zero fishing mortality. Converted into biomass, the estimate (61% of unexploited biomass) lay midway between those of two biomass-per-recruit (B/R) models for the same population based on angling and diving surveys (i.e. 52% and 69% of unexploited biomass respectively). The extrapolated CPUE at zero fishing mortality (4.4 fish angler-hour-1) in this study compared well with the mean CPUE of 4.6 fish angler-hour-1 determined during a concomitant survey in the core area of the nearby Tsitsikamma MPA - the oldest, and one of the largest, MPAs in Africa. Extrapolations of CPUE have the potential to deliver reliable and consistent estimates of stock status and could offer a practical alternative to conventional B/R models. [ABSTRACT FROM AUTHOR]