. >> reporter: this is the port of echizen, home port to more than 50 crab fishing boats. a local man helps the fishermen with their problems. he is a veteran diver. during crab season he's on call 24 hours a day to help on the boat. >> translator: i like to solve problems as soon as possible. fishermen and their families depend on their catch for their livelihood. >> reporter: every day without exception he checks the weather forecast and the height of the waves. he'll even rush to port late at night if a fisherman calls. he's got an emergency call this day. >> translator: it's a boat caught up in its own net. so i'm going out to check it. >> reporter: the boat returned to harbor. but it had to be towed. >> translator: what's going on? >> translator: the problem could be where the red and white nets are connected. >> reporter: he swims toward the bottom of the boat with a search light. the fish net is tangled in the screw propeller. he reports back to the captain with underwater pictures. >> translator: go ahead and cut the net. >> translator: are you sure? >> reporter: c