A dead adolescent whale which washed up on a KwaZulu-Natal south coast beach on Saturday has been hacked by locals eager to get a piece of the marine mammal.

The whale, believed to be a humpback, beached about 1km north of Shelly Beach around 5pm.

Since Saturday, locals have flooded to the spot either to view the whale or cut out a piece of it.

Brenda Johnson, a secretary at the Shelly Beach ski boat club, told SowetanLIVE's sister publication TimesLIVE  the whale was "apparently bleeding from its head".

"No one really knows what happened. People have been cutting and removing pieces of it since it washed up," said Johnson.

It is understood the local authority was still deciding how to remove the whale from the rocky area where it beached.