. >> meet chris fischer.n experienced ex lorer h"@ helped start the research group called ocearch. extraordary -- to study@some of the largest and most dely of the largest and most dely white shark#. >> it's interesting, you know, i didn't understand how important sharks were@to the future of the planet when i began this journey. i'm just someone who loves the ocean. but it turns out, sharks are the top of the food chain. they are the lion of the ocean@-- the great balance keeper. arks, we're going to harm the ocean's delicate ecosys$em, as well. >> so, one of the things we see happen in some areas is, if you remo the sharks, the squ explode like locusts. and then they eat all the bait fish, and the other fish have nothing to eat, and they decline, and you end up with a >> and that's where ocearch comes in. they've launche a long-term %oject to study these giants of the deep. >> well, in an effort to make sure we could look after the future of sharks, we had to have the information necessary to manage their f