If you don't bother to read scientific papers about the present condition of our oceans, you can simply watch the impressive lecture given by Jeremy Jackson at UCLA (University of California, Los Angeles).
"Brave new ocean"
Jeremy Jackson is a marine ecologist based at Scripps Institute of Oceanography. In 2003, Jackson and Daniel Pauly co-founded ‘The Shifting Baselines Ocean Media Project’ to help promote a wider understanding and use of the term in discussions of general conservation. Shifting Baselines is a sort of partnership between ocean conservation and Hollywood to help bring attention to the severity of ocean decline, to point out that the changes people saw in their 20th-century lifetimes were just small snapshots in a larger picture of environmental decline that has been accelerating for 200 years.
For more information:
"Every ecosystem I studied is unrecognizably different from when I started. I have a son who is 30, and I used to take him snorkelling on the reefs in Jamaica to show him all the beautiful corals there. I have a daughter who is 17... I can't show her anything but heaps of seaweed."
-- Jeremy Jackson