If Japan is a traditional whaling country, why do they have to send their ships all the way to the South Atlantic?

First of all, there a tenuous link at best between modern Japanese whaling and the few villages that have had this industry for hundreds of years. The technology for modern whaling came entirely from the West and it was Western countries,ironically, that hunted most of the whales in Japanese waters close to zero. It was also, by the way,the American occupation authorities that gave the biggest boost to postwar Japanese whaling

More on this topical topic on the Japanese Whaling explained page on your right.