I hear that whale watching season starts in June. Is there a chance that they'll be there in May? Also, where would be the best place to watch them?
Whales are not very common in may, best time is around September and best place is a little town called Hermanus.... but you never know...
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Whale season generally does start in June and yes Hermanus is the best place to view them. I can tell you I was there this past May and stayed in St James St in the False Bay Area. I woke up one morning to see a large pod of dolphins swimming by and a other morning saw 2-3 whales swimming by. All from my window. There are cage diving tours to seal island and boat tours to seal island in May. In June, the "airjaws" season begins where you get to see shark predation.