Lots of creatures live off fish — including me and my seabird friends. Until recently, people shared some of the fish with the rest of us because they only had simple ways of catching them: lines and hooks or hand nets. Then came fossil fuels and modern technology which meant people could build powerful boats (called trawlers) and spot fish shoals (using sonar — a way of 'seeing' underwater with sound, just as dolphins do). Then they could just sweep them up out of the sea by the millions of tons . Another disaster for us animals who depended on the fish for our food because soon there were none left in some of the once-rich fishing grounds. And people haven’t learned from their mistakes. Having ruined some of the best fishing grounds, they’re now doing the same with the remaining ones. If that wasn’t bad enough, humans are now catching the tiny creatures called krill that the fish and some whales in the great southern oceans depend on to live. Krill eat tiny floating plants (phytoplankton) and are a basic part of the food chain in these oceans.
Modern industrial fishing is on quite a different scale to someone with a net or a rod and line. Here's why:
Around 90 million metric tons each year!