Is it permissible to consume whales?
In the Name of Allah, the Most Gracious, the Most Merciful.
According to the HanafiMazhab, it is only permissible to eat from the ocean all aquatic creatures which are classified as Samak (fish). A fish is classified as any aquatic creature possessing a “backbone/vertebrae”.
Whale (origin Old English hwæl from Proto-Germanic *hwalaz) is the common name for various marine mammals of the order Cetacea.Whales are mammals. They are more closely related to humans than to the many fish and creatures which they share the oceans with. Like us, they are warm blooded, give birth to live young and they suckle their young. 
And Allah Ta’āla Knows Best
Mufti Ismail Desai,
Durban, South Africa
Checked and Approved by,
Mufti Ebrahim Desai.