We had a showdown today just off of Rottnest Island as a protective mother Humpback defended her calf from a 1.5 meter shark that had been sighted in the area. Full body breaches had all 30+ tonnes landing on the surface and we could see in the distance her body clear from the ocean below shortly followed by massive plumes of white water. Her calf also breached a few times to help mum out but it wasn't long before mum had her little one close and they left the area in a big hurry before finally calming back down again close to us.
We have sighted this behaviour many times where a mother and calf pod will go from a resting sate to full defence mode with maximum energy and aggression in their surface activity. Shortly after they will gather their calf and leave the area at high speed before slowing down in a more suitable resting spot. Sharks do not always need to bite a whale to get this response, they can just be in the vicinity of a whales reactionary distance and most of the time they will be sure to let the shark know their thoughts!