The sheer vastness of the oceans on this planet make it seem almost impossible that our actions could bring them to the point of no return, but a new report has found that we are causing an alarming decline of marine ecosystems and the species who rely on them.According to the World Wildlife Fund‘s (WWF) recently released Living Blue Planet Report, marine populations have declined by an astonishing 49 percent between 1970 and 2012, with with some fish species, including tuna, declining by almost 75 percent.