Changes in the oceans have impacted marine ecosystems and negative impacts of climate change are expected for food security, local cultures and livelihoods. These impacts on ecosystem services already have negative consequences for the health and well-being of indigenous people and local communities dependent on fisheries.
WWF South Africa was part of research and a 2020 publication on Small-scale fisheries in a warming ocean: exploring adaptation to climate change. This reveals alarming insights from some of our popular fisheries in South Africa. According to the report, “Small-scale fisheries are by no means ‘small’ and appear to have an outsized impact on human health and nutrition, poverty alleviation, jobs, and the structure of seafood markets. Small-scale fisheries likely land nearly half the world’s seafood, playing a critical role in food security and nutrition, especially for those living in poverty. “
Workshops were held with fishers and other stakeholders 3 countries, including South Africa. Local indigenous knowledge is a valuable source of information to guide fisheries management towards greater sustainability, as it’s essential to involve the fishers themselves in decisions about their future. Fishers were asked to list the changes they observed during the last 10 years. They listed a lot of changes, which were grouped into three main categories: (1) climatic conditions, (2) impacts on the ecology and biology of marine resources, and (3) fishing practices.
(1) Changes in climatic conditions already observed locally by stakeholders and attributed to climate change in the last 10 years were increased seawater temperature and strength of winds. It appears that climate change is already a tangible reality for most The effects this has on marine resources and fishing activities can also be observed.
Among the changes observed by fishers and other stakeholders were that in (2) ecology and biology of marine resources. Some of the observations include:
- Decrease in fish availability, either due to a decrease in fish abundance or the change in fish distribution (further offshore or deeper).
- Changes in trophic relationships, either regarding fish predators or seabirds.
- In South Africa, fishers remembered seeing fewer seabirds.
- Changes in seasonality and species life cycle, inducing disturbances in fishing practices.
- Some species being found in different places at the same time of the year, pushing fishers to travel further to catch the fish. This already happening with snoek along our coast.
Changes in (3) fishing activities and practices have already been observed locally by stakeholders:
- Increase in distance to the shore for fishing
- Reduced fishing yields
- Reduced areas to fish
- Reduced number of suitable fishing days
- Increase in the number of fishers.
In South Africa fishers listed a lot of already significant changes in their activity because of climate change, in particular decreasing catches meaning they should go fishing farther offshore. This is a clear sign that climate change doesn’t just pose a threat to our marine species, but to fishers and those who depend on our oceans the most.
Climate effects on South African species in the line fishery were also explored in the study which was identified as being the most vulnerable fishery towards climate change.
The report assessed species vulnerability to change i.e. their relative temperature sensitivity and adaptive capacity and the potential regional extent of such changes, along with the species’ individual degrees of exposure.
One of the major linefish species is SASSI green-listed favourite, snoek. Snoek appears on the edge of its temperature range and will probably be severely impacted by sea warming, even if actions are taken to prevent this. This suggests that the low vulnerability index found for snoek is not sufficient to assess the potential impact of climate change as the species prefers rather cool waters and will suffer from the sea warming. Snoek has a medium risk of climate impact. Carpenter seabream also appears on the edge of their temperature range and will probably be severely impacted by sea warming, even in the case of a strong mitigation scenario. Carpenter is green listed for the line fishery and its stock status is optimally exploited, yet it is one of the most threatened species in terms of biomass. Carpenter seabream has a medium risk of climate impact and is highly vulnerable to climate change. The species has a particularly high risk of impact linked to temperature. Red-listed geelbek, also known as Cape salmon is classified as highly vulnerable, but is in fact a species already living in hot temperatures and thus it will probably suffer less from the sea warming expected in the South African EEZ, even in the worst climate change scenario. Geelbek is on the SASSI red list and is considered a collapsed species. Geelbek has a high vulnerability and high risk of impact linked to climate change. It is also one of the most threatened species in terms of biomass.
Fisheries that are successfully managed to achieve resource sustainability will be better positioned in the long term to adapt to the effects of climate change. This is because marine resources are likely to be more robust to the effects of climate change if the compounding stresses from overfishing, habitat degradation, pollution and other anthropogenic factors are reduced.
Adaptive fisheries management was proposed in the study the form of: Enforcement of effective monitoring, control and surveillance; Precautionary targets and an ecosystem-based approach; and Research on fisheries adaptation. Mitigation suggestions include reduction of greenhouse gases such as: Reducing fishing vessel speed; Replacing towed fishing gears with passive gears; Increasing fuel and vessel efficiency, etc.
With all study participants acknowledging that the effects of climate change are already visible in their fisheries, it was immediately clear that local ecological knowledge and multi-stakeholder co-management will be key to adapting to a sustainable future for the small-scale sector. We are all beneficiaries of our oceans and we need to positively impact our environment, in order to have our best shot.
Kirtanya Lutchminarayan, WWF-SASSI Project Officer