Yesterday, 29 Feb 2012, the City of Cape Town issued a press release of a proposal to trial an exclusion net in Fish Hoek Bay (http://sharkspotters.org.za/media-release-city-to-consider-a-proposed-trial-installation-of-a-shark-exclusion-net-for-fish-hoek-beach). Almost immediately shark nets (as used in KwaZulu Natal) were confused with the proposal of the exclusion net in Fish Hoek. Below is a summary of the key differences. Please post your view of what you think of the City’s idea on our Facebook page and we will be sure to feed it back to the authorities.
|Shark net||Exclusion net|
|What are they?||Shark nets are large-meshed, anchored gill nets||Exclusion nets are fine-meshed nets and are not gill nets|
|How do they work?||Entangle and catch sharks reducing the population and numbers of sharks within the environment and thereby reducing the risk of shark attack||Fine meshed nets are designed to act as a barrier, physically excluding sharks, thereby preventing them from entering an enclosed area|
|Layout and structure||Nets are 213.5 – 304.8 m long by 6.3 m deep, have a black mesh of 51 cm (stretched) and are set parallel to the coast in 10-14 m of water some 300-500 m from shore.||Net is set to enclose a specified area, and stretches from the seafloor to the surface. Mesh size is 6cm stretched (3cm x 3cm on the square). Size of net is dependent on area to be enclosed.|
|Entanglements of marine animals||Not selective and result in by-catch of a range of other marine species such as turtles, dolphins, and whales. Risk of entanglement high||The fine mesh of the nets prevents capture or entanglement of marine species and the net acts as a barrier. Risk of entanglement low.|
|Areas where used||KZN (South Africa), Australia||Hong Kong, Seychelles|
One of the proposed layouts of an exclusion net in Fish Hoek (Courtesy City of Cape Town: email@example.com)