( CNN ) -- `` Planet in Peril : Battle Lines '' traveled to a place off the coast of South Africa known as `` shark alley , '' one of the best places in the world to see great white sharks . CNN traveled to `` shark alley '' off the coast of South Africa , one of the best places in the world to see great whites . Shark tourism has become big business , bringing in more than $ 30 million every year to South Africa . The experience is a major draw for tourists , but it 's controversial . Local surfers and swimmers say it is changing shark behavior and may be causing more attacks . Anderson Cooper swam with these great white sharks -- without a cage -- as part of his report for `` Planet in Peril : Battle Lines . '' He talked about the experience Thursday morning with `` American Morning '' anchors John Roberts and Kiran Chetry . Anderson Cooper : We went diving with great white sharks . There is a big controversy over whether or not these cage tour operators are actually changing sharks ' behavior . They chum the water to attract the sharks , tourists get in the water , and so we had the opportunity to go cage diving and also to go free diving with the sharks , which is a pretty rare thing . There 's not many people on the planet who actually do it , probably for very smart reasons . You 'll see that tonight on `` Planet in Peril . '' Actually , swimming with great white sharks without a cage , which is among the most remarkable experiences of my life , I 've got to say . Anderson dives with great whites » . Kiran Chetry : What do they call that , a free dive with sharks ? Cooper : Yeah , we went free diving with the sharks . The water is chummed with blood , so it 's bloody water , and I was just about to get in , and I turned to the guy and said , `` Do you have any recommendations ? ' '' And he said , `` Project confidence . '' See how great white sharks are lured to the surface » Chetry : There you go . Thanks . John Roberts : He also told you not to breathe , right , because they do n't like the noise of the bubbles ? Cooper : Right , they do n't like air bubbles . Roberts : So , meantime you 're down there hyperventilating . Cooper : It 's all well and good to say `` OK , do n't take a breath , '' but your heart is beating so fast when a huge great white shark is close to you , that you ca n't hold your breath . So I was actually breathing more and causing more air bubbles . And the sharks open up their mouths and extend their jaws when they 're nervous , and that makes me very nervous . Roberts : You 're reminded of when Roy Scheider [ in the movie `` Jaws '' ] said , `` We 're gon na need a bigger boat . '' Cooper : For me , I think it was , `` I need to get back in the boat . ''
Anderson Cooper was free diving with great white sharks in South Africa . Before the bloody water , guide advised him to ` ` project confidence '' Cooper : Free diving was ` ` among the most remarkable experiences of my life ''