Kelp Cutting, The Good/Bad

Written By : Walkerbay Dive School
February 29, 2020

What is kelp cutting?

Kelp cutting in Cape Town, South Africa is a major operation that has been making progress around from Simon’s Town all the way to Danger Point in Gansbaai. Kelp is widely used for toothpastes, herbal ointments, drinks, food etc. One of the biggest uses for kelp is in abalone farms where it is used to add nutrition to the water.

What is the purpose of kelp in the ocean?

The structure of kelp consists out of the holdfast that anchors the plant to the reef, the stipe that acts like a stem followed by the long leaves called blades with gas bubbles attatched to them that heeps the top of the plant afloat. Kelp can be a “Building structure” where many species thrive. Not only does it provide food for sea urchins at the base of the plant, but a home for the crab families in the top leaves. Otters float between the kelp forests to keep from drifting away and they also make a meal out of the sea urchins that live at the kelp’s base. Kelp also helps to break up some of the force of the waves and currents in certain areas.

How do they cut the kelp?

Kelp can be cut in two ways. Firstly the old fashioned way where divers go down and cut the stipe at about 30 cm from the base. The gas bubbles then makes the plant float to the surface where it can be collected by hand and hulled back to land for processing.

The second way is when a big vessel is used to electronically cut the kelp without damaging the seafloor. As soon as the kelp reaches the surface, giant comb like fingers pick the kelp up and transfers it into the vessel.

How does this effect our ecosystems?

Ecosystems has many different parts that makes the removing of kelp a major problem in certain areas. Kelp that is being removed creates open spaces that makes species such as the Great White shark come closer to shore, this influences other species that has never known this kind of predator. Sea urchins will start over populating the reef seeing as there are no more otters to help control the population. Tides that push in and out will now do so with more force to the areas where there is no more kelp . Our ocean already faces chemical pollution, plastic pollution, overfishing and poaching yet we as humans take out the kelp forests and expect no consiquences…..

How can we better this situation?

Keeping track of the growth of these forests are vitally important to us and our ecosystems, many marine teams have been deployed in the areas of Simon’s Town and in Cape Town. The growth of these forests are not only dependant on our next steps but also on our own pollution proble. The more we cut these plants and pollute the ocean, the more they will start dying. Many species are forced to leave their territories and make for a new home but some just go extinct without us knowing about it!

Suspicious activity around kelp forests can be reported at the Marine protection Office at 021 783 0234.