A "Facebook for fish" is being used to try and save the critically-endangered Giant Sea Bass. This is just one of the pioneering experiments being carried out by marine biologist, Douglas McCauley, in his mission to protect ocean life.<br /><br />Click here to subscribe to The Economist on YouTube: https://econ.st/2xOgV2D <br /><br />For more from Economist Films visit: https://econ.st/2xOgVzF <br />Check out The Economist’s full video catalogue: http://econ.st/20IehQk <br />Like The Economist on Facebook: https://econ.st/2xOgWDJ <br />Follow The Economist on Twitter: https://econ.st/2xQLtRy <br />Follow us on Instagram: https://econ.st/2xNhARR <br />Follow us on Medium: https://econ.st/2xOgYvl