Remove The Nets

Harmless blacktip shark on the dissection table at Sharks Board.

Like them or not, sharks play a crucial role on this planet. Remove sharks from the oceans and we are tampering with our primary food and air sources. And the livelihoods of millions that rely on the oceans for their main source of income.

Sharks play a critical role in our oceans – the world’s largest and most important ecosystem. Ocean’s provide billions of tons of foods each year, and more oxygen to this planet than all the rain forests combined.

As the apex predators of the oceans, the role of sharks is to keep other marine life in healthy balance. Remove sharks and that balance is seriously upset. Scientific studies show that elimination of sharks can cause disastrous effects including the collapse of fisheries and the death of coral reefs.

One study in the U.S. indicates that the elimination of sharks resulted in the destruction of the shellfish industry in waters off the mid-Atlantic states of the United States, due to the unchecked population growth of cow-nose rays, whose mainstay is scallops. Other studies in Belize have shown reef systems falling into extreme decline when the sharks have been over-fished. Without predators, the grouper population spiked, which in turn reduced the natural balanced population of algae-eating fish such as the parrot fish, and the coral became overgrown with algae, destroying an entire ecosystem.

On the East Coast of South Africa, the nets have already been linked as one contributing factor to an upset in the ecosystem due to the steep decline of the zambezi shark population – as noted by KwaZulu-Natal Sharks Board scientists themselves.

The impact of the nets. There are less than 500 of this species in Australia - another country with nets.

Nets work by reducing localized shark populations, and during their 60 years of installation in Natal, have had a significant impact on those populations, as per studies conducting by Sharks Board themselves.

The population of sharks – particularly those targeted by nets – are drastically reduced in the Eastern Cape to their numbers prior to the nets installation, thanks in part to the meshing program. If the nets were removed, due to the slow reproductive and maturity rates of sharks, it would take decades for shark populations to recover. Given all the other threats to sharks including habitat destruction and overfishing, it is questionable if the local populations will ever recover. The nets have spent years doing their damage. Removing them at this point would not have an immediate impact.

While data was not effectively collected until 1978, anecdotal data available suggests records of very large numbers of sharks caught when meshing was begun. While annual total shark catches can fluctuate sharply, there is no question that today shark populations are very much smaller than in the 1950‘s & 60’s when attack rates were higher. In Durban, the total catch in the nets was 552 sharks the first year the seven nets were installed. By the second year it had plummeted to 182.

And, many people do not realize that one of the primary reasons nets were installed was due to the whaling that occurred off the coast of Durban. Shark populations were abnormally high due to the remains from the whaling stations that operated off the coast until 1975, providing sharks with a constant source of food. Whale oil and meat, which is a strong attractant to sharks, flowed from Durban beaches to the north or Amanzimtoti to the south - the exact sites of the most shark attacks during the peak of the whaling industry. With this source of food no longer available, it is unlikely shark populations will ever attain the sizes of those off Durban in the 50’s & 60’s.

The end of whaling in 1975 should have signified the reduction and removal of the nets, as shark numbers would have normalized, and there were no longer attractants luring sharks into situations that easily result in attacks. However, 1975 also saw the release of “Jaws”, and the sharks’ fate was sealed for another 30 years.