Japanese whaling ships set out to hunt some 300 whales in the name of science after reworking its programme in accordance with an international treaty on scientific whaling.
The Japanese whaling fleet is set to resume the slaughter after a one-year break, in what many are calling a "crime against nature".
Japan continues to argue that its whaling is done for scientific reasons, despite opposition from many countries, including New Zealand.
The country claims that it is trying to prove that the whale population can sustain a return to commercial whale hunting and argues that killing them is part of conducting that research.
In spite of its "scientific reasons", the whale meat ends up on the dinner table and in school lunches.
After a UN ruling in 2014, Japan has sent the last year conducting "non-lethal" research only, taking only whale skin samples. However, the Japanese government says it will now resume its regular hunting season, which runs through to March.
Sea Shepherd has already said it will follow Japans vessels while the country aims to kill a total of 333 winke whales.
Japan could become the next target of the 'Anonymous' cyber hackers group that has launched an assault on Iceland for its views on whaling.
'Anonymous' activists claimed responsibility for shutting down five Icelandic government websites on Friday, which remained inaccessible until midday Saturday last week.
The group posted a video online explaining the action.
"Whales do not have a voice. We will be a voice for them. It's time to speak out about this impending extinction of a species. It's time to let Iceland know we will not stand by and watch as they drive this animal to extinction," a group spokesperson says.
Iceland is one of three countries, including Japan and Norway, that endorses whaling.