Beachgoers walk past colour coded shark warning flags, black indicating poor visibility, on Cape Town's Fish Hoek beach, April 25, 2012. Fish Hoek lies on the edge of False Bay, home to a large concentration of Great White sharks. A fatal shark attack a week ago has triggered a wave of anger against the practise of chumming, the luring of great white sharks with a smelly mixture of fish and oil by tour operators and researchers, with surfers and swimmers calling for a ban on the practice. REUTERS/Mike Hutchings (SOUTH AFRICA - Tags: ENVIRONMENT)