Delve into the underwater world of Cape Town’s kelp forests with Jethro, a local freediver and environmentalist. Explaining the vital ecological role of these marine landscapes and sharing the importance of their conservation, Jethro illuminates their beauty and significance.
With imagery captured by talented photographers, explore the towering kelp fronds, learn about their unique biodiversity, and understand their cultural and economic importance to the local community.
Header image: The magical kelp forest from above. Photo: Jason Boswell
So what are kelp forests?
A kelp forest is a unique underwater ecosystem that’s comprised of a type of large, brown seaweed known as kelp. Just like terrestrial forests, kelp forests are characterized by high levels of biodiversity and complex three-dimensional structures.
Kelp, which is a type of macroalgae, can grow remarkably fast in conditions where sunlight, temperature, and nutrient levels are ideal. Some species can grow up to 45 centimetres (18 inches) per day, reaching heights of over 45 meters (150 feet)! They possess a root-like structure called a holdfast that anchors them to the ocean floor, and a stem-like structure called a stipe that connects the holdfast and the leaf-like blades.
Some kelp species also have gas-filled bladders that help the blades reach towards the sunlight at the ocean’s surface, forming a canopy.
This architecture creates different layers or zones in the kelp forest: the canopy at the top, the understory in the middle, and the bottom layer near the ocean floor. Each zone has distinct light, temperature, and nutrient conditions, and harbours different species of marine life.
Digging deeper into Cape Town’s kelp forests
Locally we call our kelp forests, the Great African Sea Forest. In local languages, it is known as the forest of the Groot Seeamboes, Imbambosi or scientifically, as Ecklonia Maxima.
South Africa’s kelp forests are dominated by two species of kelp: Ecklonia maxima, also known as sea bamboo, and Laminaria pallida. Sea bamboo, the larger of the two, can grow up to 12 meters (39 feet) tall, creating a dense underwater forest that provides shelter and food for many species. Laminaria pallida tends to grow in deeper or more turbulent waters where sea bamboo can’t thrive.
These kelp forests are found along the western and southern coasts of South Africa, in the Benguela Current. This region is characterized by upwelling, where cold, nutrient-rich water rises from the deep sea to the surface, providing an abundance of nutrients for kelp growth.
Why they’re important, environmentally and culturally
Spotted Gully Sharks swimming in the Kelp Forest; Photo by Danel Wentzel
The kelp forest ecosystem is the most biodiverse ecosystem in the world, where you can find all sorts of creatures in all shapes and sizes. They can range from the minuscule brightly-coloured nudibranch to the shy and elusive Spotted Gully Shark. Kelp forests are used by marine creatures mainly as a nursery for their young, protection from predators, and food.
Everything is interconnected. If you remove one component, everything will collapse. For example, overfishing predatory species can lead to an overpopulation of sea urchins, which can then overgraze the kelp, leading to what is called an “urchin barren.” A once rich and diverse kelp ecosystem turns into a sort of semi-desert. So maintaining a balance is vital!
Kelp forests’ importance to humans
Not only is the kelp forest valuable to these amazing marine creatures, they are also very valuable to us humans. In South Africa there is a growing awareness and connection with kelp forests. With the growth of an already established diving community, we have seen an increase in one-on-one access and connection with our forests in particular.
Red Roman swimming in the Kelp Forest; Photo by Ben Wiid
Over centuries kelp forests have been a critical source of food for coastal communities, particularly the small-scale fishing communities which have been active for generations. Fishermen in these communities grew up spending time in the local harbour learning from their elders about ways of fishing, how the ocean works, and how to support their families by making fishing a livelihood. Because fishermen depend on the ocean for their livelihood, they are some of its greatest defenders, ensuring that the oceans are protected and not exploited.
Small-scale fishing boats in the fishing community of Kalk Bay; Photo by Gunnar Oberhoesel
Kelp forests are also used as a source of tourism and income by local businesses. Some local businesses such as dive centres use kelp forests as a place to teach their students how to become divers or simply to explore all that can be found in these forests. South Africa has a unique ecosystem that can’t be found anywhere else. As a result, many people visit our country to explore these beautiful underwater forests.
With that said, it is crucial that we protect these forests to ensure the longevity of these ecosystems and the economical benefits that come from these habitats.
What we can do to ensure they’re protected and thriving
Everyone can do their bit to ensure that our Kelp Forests and oceans are protected for years to come. You can start small, whether it may be attending beach clean-ups or trying by all means to reduce the amount of single-use plastic that you use on a daily basis.
It has been estimated that by the year 2050 there may be more plastic in our oceans than fish, which is really alarming. This shows that plastic is a design failure and it’s now our chance to work together to make sure that this estimation doesn’t become a reality.
As previously mentioned, one of the best things to do is to avoid the usage of single-use plastic. This gesture will not only help heal our oceans and their ecosystems, but also force companies to reduce their plastic production. Consider using reusable products such as reusable shopping bags, metal water bottles, etc.
Plastic travels in more ways than imaginable. No matter where you are or live, plastic will find its way into our oceans and subsequently into our kelp forests thus harming our ecosystems.
A piece of plastic that found its way into the Kelp Forest; Photo by Danel Wentzel
Cleaning up plastic
A lot of times when you go into the kelp forests for a dive or to explore, you will come across pieces of plastic. Sadly a lot of plastic ends up in our kelp forests and can threaten the creatures that live in these ecosystems.
An easy way to remove this threat is to retrieve the piece of plastic and put it in your wetsuit. When you return to shore you can put it into the nearest bin. This is one way to explore the kelp forest while giving back to it.
In addition to picking up pieces of plastic when you are exploring the kelp forests, you can join underwater clean-ups that regularly happen in our surrounding areas. These land and underwater clean-ups are a way for our communities to ensure that our kelp forests are protected.
Local community clean-up spearheaded by Sentinel Ocean Alliance; Photo by Gunnar Oberhoesel
Increasing Marine Protected Areas
One cause that will have a more direct impact on kelp forests, is the importance of Marine Protected areas. On land we have nature reserves that are set up to protect the fauna and flora within their boundaries — Marine Protected Areas are exactly that but for our ocean!
Marine protected areas (MPAs) are vital for conserving ocean biodiversity and protecting vulnerable species. They safeguard areas where uniquely sensitive ecosystems can be found, and lessen overfishing, pollution, and habitat destruction.
As a freediver who has dived in both protected and non-protected areas. I can personally vouch for the impact of these protected areas. Marine life is more plentiful here. It is vital to protect these areas whether it is through advocacy or via a scientific approach.
A Hottentot swimming in the rich and plentiful kelp forest within an MPA; Photo by Ben Wiid
A more hands-on scientific approach
A scuba diver from Cape RADD doing citizen science; Photo by Cape RADD
If you want to take a more scientific approach to protecting our oceans, there are many citizen science initiatives you can participate in such as Cape RADD’s citizen science snorkelling and scuba diving trips. During these trips, you get to experience the kelp forests first-hand while participating in data capturing, research and assessments of these amazing ecosystems. Should you wish to instead go on a snorkelling or diving excursion, there are many dive centres & marine guides that would be more than happy to take you into the kelp forests.
Exploring the Kelp Forest
Tourists before leaving for a snorkelling trip with Cape RADD; Photo by Cape RADD
It is best to go with people who are informed about kelp forests when snorkelling, freediving and scuba diving in Cape Town. The best dive sites to go to are located in Simons Town, False Bay. There are many dive centres and marine guides based here, a favourite being Impact Divers based at the False Bay yacht club. Impact dives offers a very hands-on service with their clients with many packages available. You can rent your own gear or alternatively go on guided diving trips. It is however important to go with experienced divers in the ocean for safety and educational reasons. Once you have your gear and someone to go with you, a whole magical world awaits you!
Scuba Divers from Impact Divers chilling in the kelp forest; Photo by Impact Divers
My personal favourite dive site
Cape Radd Snorkellers exploring the shallows of Windmill Beach; Photo by Cape RADD
My personal favourite site, Windmill Beach, is incredibly easy to access for anyone who wants to dive. There is ample parking, however, it can get packed during hot summer days! It is recommended to visit Windmill Beach if you are just starting out as it is sheltered and a haven for marine life as a result of it being a Marine Protected Area.
Some of the incredible species that hang out at this site are countless common octopus, numerous fish species, pyjama sharks, the magical Short-tail stingray, and if you are lucky the resident seal can also be spotted. This is why marine protected areas are important as they play host to marine creatures in a safe and protected environment for all to see. Just note that Windmill Beach is just one of the many amazing dive sites in Simons Town.
Some last words from myself
Myself in the kelp forest off Windmill Beach; Photo by Dani Minutelli
From a personal perspective, I implore you to explore our oceans and especially our abundant kelp forests. It is a gift to have them and like all gifts, it is important to protect them. Our next generation deserves to see what we are lucky enough to see and experience. It is up to us to protect our kelp forests, marine life and planet as a whole while additionally encouraging the next generation to do the same.
My friend Loyiso Dunga puts it nicely, “If you bend the bark of the tree while it’s still young, then you can shape it towards whatever direction you desire”, it is up to us to bend and shape the next generation to be custodians of our oceans and our kelp forests.
Myself at a beach clean-up hosted by Sentinel Ocean Alliance; Photo by Gunnar Oberhoesel
In conclusion, I would like to thank those who have given some input in this article, those people being Kholofelo Sethebe and Loyiso Dunga. Lastly, I want to give a huge shout-out to all the amazing divers and photographers who have contributed some photos for this article. Having said that, go out and explore but most importantly, let your future begin!
About the author: Jethro is a freediver, mental health advocate and environmentalist based in Cape Town, focusing on ocean conservation. Since the age of 13 he has championed the cause to protect our oceans. When he isn’t diving, you will find him exploring Cape Town or camping in the Cederberg. For more about him, head to his link tree or website.
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