Could very well be. Well spotted.
Whales found in that area are
Southern Right Whales which average around 15-18 metres:

and the
Humpback Whale which average around 12 - 14 metres:

But if it
is a whale, I'd go for the Southern Right, because of the apparent lack of those colossal pectoral fins.
It'd be a real shame is if it's
any kind of whale though, as there aren't as many left in the world as we'd like.