About fish

It is said that the world's fish and seafood population will collapse by 2048 if habitat destruction and over fishing continue. What do you think? I was really surprised. I think that there are fish and seafood always around us. We, Japanese, get a lot of nutrition from them and to have them is our pleasure. We can't live without them. Besides, there are other problem about fish and seafood. When I was a high school student, I studied that there are shellfish which we can't distinguish the sex because of the abnormality of ecosystem. What if fish and seafood collapse in all over the world? Probably food chain will collapse completely. We are going to destroy ourselves... What should we do? Please tell me your opinion.