This video says about itself:
27 January 2017
In the Pacific, a tiny island 300 miles away from the shore hides a giant mountain beneath the waves that forms a home for thousands of plankton feeding fish. These fish attract tuna, and the tuna attract thousands of sharks. Watch this video to learn more about this fascinating food chain, and hear some weird but true facts about the visiting hammerhead sharks..
Taken From Blue Planet Series 1.