The shark attack near Cape Town on Monday has shocked local residents and tourists alike. A huge great white shark bit local resident Tyna Webb in half during her daily morning swim.

Unfortunately it has led to renewed calls to place shark nets at Cape beaches. While shark nets have been shown to reduce the (already small) chance of swimmers being attacked by sharks, they have a dirty little secret: they kill dolphins.

Around 60 dolphins a year get caught in the shark nets off the main beaches of Kwazulu-Natal on South Africa's east coast. Dolphins drown if they cannot reach the surface for air.

The shark nets were originally placed at Kwazulu-Natal beaches after "black December" in 1957 when a series of horrific shark attacks killed 5 people near Margate. Although it is now generally recognized that this was a freak incident, possibly related to the discharge of blood into the sea from whaling stations along the coast.

Humans are irrational about risks. Only 6 people are killed in shark attacks a year world-wide. Compare that to the number of victims of traffic accidents (10,000 a year in South Africa alone). There seems to be something terrifying to the human mind about a wild creature or uncontrolled nature.

Of course, the real force behind calls to install shark nets will come from the tourist industry claiming lost income and opportunities. Capitalism can be incredibly selfish, stupid and short-sighted. I hope that true lovers of the ocean will be able to counter this inevitable pressure.

Isabelle Spies, one of Tyna's daughters, said that "a revenge attack would be the last thing that my mom, who was such a gentle person, would want".

"She said that she respected the shark's dominion, that when she went swimming she knew she was entering their domain. My mom's wishes should be respected. She was the person who was attacked, after all."

"A fatal attack is such a rare thing. More important than killing the shark, there should be a look at why there have been more attacks recently."

Geremy Cliff, head of research for the Natal Sharks Board, said it cost R1-million annually to maintain the shark nets at Amanzimtoti. The nets caught around 60 dolphins, 60 turtles, 200 rays and 600 sharks each year. Most of these animals died before they could be freed.

Cape Times, November 17 2004

See also:
National Geographic article about shark net debate
Shark net dilemma for whales in Australia