Spear fishing had been practiced in SA waters for many decades. Some excellent literature exists on the topic, specific to our own fish species and dive spots.
The South African coastline offers world-class spear fishing, but you have to know the where/when/how of this kind of hunting.
Fortunately the spearing of reef fish is banned on much of the coast, including the clear water stretch from St Lucia mouth to Kosi Bay.
The West Coast is rough, cold and dirty – good only for crayfish and perlemoen (abalone) most of the time. Timing it right, one can take Galjoen, Hottentot and the like in protected kelp bays.
From Cape Point to the Wild Coast offers cool but dive able water, frequently clear enough for spear fishing. Favorite game fish is Yellowtail and Garrick. South Coast and higher up presents warmer, cleaner waters with Great Barracuda, Natal Snoek, King, Queen and similar. In the Sordwana/Kosi area the chances of good water is almost guaranteed throughout the year. (Hence the popularity of Maputoland for scuba).
Sharks are there to be respected for who they are. Fortunately the most experienced spearos are the ones that dive the places when Megasharka Bitasoras makes a nuisance of itself. Hence the low statistics of nasty incidents.
Clubs exist all along the coast and inland in the main centers.
Most spearos enjoy the odd scuba dive too.