Zambezi populations have plummeted since the nets have been installed.

Given the grave situation shark populations are in, anything that threatens a shark population – even locally – can impact worldwide numbers. Additionally, KwaZulu-Natal Sharks Board indicated in 2006 that nets, amongst other factors, had an impact on the population of six shark species including zambezi sharks, dusky sharks and scalloped hammerheads. And while shark nets are unlikely to result in an extinction alone, they are preventing populations from recovering, further threatening already stressed species.

Indeed, in Australia, another country with shark net installations, the grey nurse shark (also known as ragged-tooth sharks locally) in Eastern Australia is in danger of extinction by 2010. Recent studies have found that shark nets and other forms of fishing have significantly increased their rapid population decline. The population of these sharks is now down to less than 500, and meshing is listed as a key threat to their survival. It is more than possible this species could suffer a similar fate in South Africa as well. Raggedtooth sharks, over the past 30 years, make up over 20% of all shark catches in the nets.

From the KwaZulu-Natal Sharks Board website: “The life history of sharks is such that they are very vulnerable to overfishing. Typically, sharks grow slowly, mature late and give birth to few young. These characteristics mean that only a small proportion of a given shark stock can be caught on a sustainable basis. Also, if a shark stock has been overfished, it takes a long time to recover.”