1Kelp: Nature’s Underwater Forest

What is Kelp?
•2

Seaweed refers to the type of marine algae that grows
in the ocean, characterized by three main types: red,brown, and green.
Kelp is brown macro (large) algae.

•Four Species of Kelp Native to South Africa
1

Ecklonia maxima

2

Ecklonia radiata3

Laminaria pallida

4Macrocystis pyrifera

3
Two of these species, Ecklonia maxima and Laminaria
pallida thrive along the Namakwa coastline of South Africa

The Importance of the Kelp Ecosystem

4 It is a carbon sink.
 Kelp provides food security:
o Nutritional cycling with high protein content
o A nutritional supplement for people and animals(e.g abalone feed).
 An important habitat and a food source forfish(sardine ,hake, rock lobster) .
 Serves to protect the coastlines by slowing the powerof waves during storm surges.
 Used for fertilizer, bioplastics, and otherpharmaceutical products.

Threats to Kelp Ecosystem

Restoration and Management

Kelp forests are predicted to decline
in abundance by 1.8% per year
globally, due to several main drivers.

Sea urchins (grazers) are crucial to the kelp
ecosystem because they break down kelp
into small pieces that can be consumed bydetritivore species for nutrients, but canbecome problematic where their numbers
exceed normal levels. Managing sea urchins
involves methods such as culling andharvesting.

Restoration Techniques:
Seeding involves cultivating or spreading
kelp seeds or gametophytes in the ocean.
This method is beneficial because it requires
fewer resources and can be grown in large
quantities.
Transplanting is the introduction of mature
kelp into the ocean. This approach isadvantageous because kelp that is at anolder life stage is more resistant to stressors
resulting in higher survival rates.

The Seaweed Industry in South Africa

Map of seaweed concession areas in South Africa by Dr. Mark Rothman

Currently, the estimated total market
worth of kelp in South Africa stands at ZAR
56.5 million. There are 23 Seaweed
concession areas, with 13 having kelp
rights (areas 5-9, 11-16 and 18-19). The
harvesting of fresh kelp in South Africa
started in the 1980s for biostimulant
production and expanded in the 1990s toinclude kelp fronds and fresh beach-castkelp harvesting for abalone feed. Initially,
the focus was mainly to collect beach-castkelp but now wild-harvested kelp is also
being processed into fertilizers, animal feed,and biostimulants. Beach cast kelp is milled
and sent for export to produce alginate.

The Namakwa Coast and Kelp
The Namakwa Coast is home to four Marine Protected Areas (Orange Shelf Edge,
Child’s Bank, Namaqua National Park and Namaqua Fossil Forest) that help toprotect and preserve some of the crucial biodiversity and species; including kelp in theregion.

Influence of The Benguela Current on Kelp

•Kelps are predominantly cold-water species, that flourish in nutrient-rich waters
and are commonly found in temperate, arctic and sub-antarctic areas.
•Namaqua coast is located along the Benguela current which is a cold, slowmoving current propelled by prevailing winds that create a coastal upwelling. It isthe cold, nutrient-rich waters from this current that fuel high rates of phytoplankton
growth; which nurtures the marine ecosystem resulting in kelp thriving in thisregion.

Blue Carbon Gaps andOpportunities for Kelp

Discovery of a “Lost Species’’
in the Kelp”

There is a growing interest in the carbon
sequestration of underwater ecosystems,with mangroves, tidal marshes, andseagrasses known as blue carbon
ecosystems. Kelp is emerging as asignificant contributor due to its ability tosequester and store carbon. However,further research is needed to measurecarbon quantities, study movement, anddeposition
dynamics,
andassessemissions from disturbances. Once theseevaluations are understood, kelp could
qualify as an actionable ecosystem.

The
criticallyendangeredDe
Winton’s GoldenMole, previouslybelieved to be extinct and known only inPort Nolloth, has been rediscovered in
McDougalls Bay after 86 years. Theseunderground insectivores appear to feed
on invertebrates found in washed-up
kelp, however further research is needed
to confirm this interaction.

The Future of the Kelp Market in South Africa
To date, the kelp market in South Africa is focused on fresh kelp and beach-castkelp harvesting. However, there is a growing interest in diversifying through methods
such as kelp aquaculture; with the total market value of kelp as abalone feedcurrently estimated at ZAR 9.8 million. Studies indicate the potential for sea-based
farming of kelp particularly in Saldanha Bay on the West Coast. While commercial
kelp farming does not exist yet in South Africa, ongoing experiments in Saldanha
Bay may lead the way for its future development.

REFERENCES
1. BSASA (Bivalve Shellfish Farmers’ Association of South Africa) 2023; Final report Kelp Value Chain
Analysis, Market Assessment and Roadmap for Development of Kelp Farming In South Africa
2. Kelp Restoration Guidebook: Lessons Learned from Kelp Restoration Projects Around the World. Available
At:https://kelpforestalliance.com/TNC-KFA-Kelp-Guidebook-2022.pdf
3. Marine Protected Areas South Africa. Available At: https://www.marineprotectedareas.org.za/
4. Mynhardt, S., Mathew, E., Pierre le Roux, J., Little, I., Bloomer, P. and Theron,C.2022. Environmental DNA
from soil reveals the presence of a “lost” Afrotherian species. Biodiversity and Conservation 33, 31-50
5. Policy Brief: Actionable Blue Carbon Ecosystems for Climate Mitigation and Adaptation. (2023)
6. Rothman, M.D., Anderson, R.J., Kandjengo, L. and Bolton, J.J. 2020. Trends in seaweed resource use andaquaculture in South Africa and Namibia over the last 30 years. Botanica Marina, 63(4), 315-325.
7. Seaweed: What is Seaweed? – Journal of Nutrition. Available At:
https://journalofnutrition.org/encyclopedia/seaweed-what-is-seaweed/
8. The Currents of South Africa. Approach Guides. Available At:
https://approachguides.com/blog/currents-south-africa-benguela- agulhas/
8. Troell, M., Robertson-Andersson, D., Anderson, R.J., Bolton, J.J., Maneveldt, G., Halling, C. and Probyn, T.
2006. Abalone farming in South Africa: An overview with perspectives on kelp resources, abalone feed,
potential for on-farm seaweed production and socio-economic importance. Aquaculture, 257, 266-281.
9. The Currents of South Africa. Approach Guides Available At: https://approachguides.com/blog/currentssouth-Africa-benguela-agulhas/
10. World Resource Institute (2023, May 2). What is Kelp and Why is it vital to people
and the planet? Available At: https://www.wri.org/insights/what-kelp-forests-protect#
11. Yorke CE, Page HM, Miller RJ. 2019. Sea urchins mediate the availability of kelp detritus to benthic
consumers. Proc. R. Soc. B 286: 20190846. Available https://dx.doi.org/10.1098/rspb.2019.0846
12. https://www.inaturalist.org/@https://www.americanoceans.org/facts/kelp-vs-seaweed/

For more information:
Julia Levin | Vice President
Conservation South Africa
Email: jlevin@conservation.org