Many behavioural antics can be witnessed at their mating and calving grounds. It should be noted that not all the behaviours described may be seen in a single whale watching expedition. Some of the more exciting behavior these graceful and acrobatic whales exhibit include:

• Breach : The whale launches itself clear of the water with three beats of its fluke and in a graceful manner may rotate on its axis and plunge back into the water either on its back or on its belly
• Round out : This is the view of a whale's back (and how the humpback got its nickname!) as it swims. A round out may indicate a deep dive
• Blow : This is the first indication of the presence of whales in the region. The blow is composed of a burst of water vapour and can be expelled at speeds of up to 450 km/hour and rise to about 3 feet. The blow can usually be seen for up to a few kilometers on a calm day
• Pec slap : The whale raises its pectoral fin and smacks the surface of the water. This is believed to be a form of communication and could be used to signal its presence to other whales.
• Pectoral fin extension : Whales sometimes lie at the surface of the water, extending and waving their large pectoral fins
• Pec stroking : Also a form of communication and a way of showing how close they are (between mothers and their calves)
• Tail slap/ fluke slap : Using its tail or fluke to slap the surface of the water. This may be used to signal aggression but as the humpbacks are largely social beings, it can also be used as a playful gesture or for communication
• Peduncle slap : Associated with aggressive behaviour (similar to a fluke slap). Combatants may try to physically displace the primary escort from the female in a "mating pod" by all sorts of physical aggression such as the peduncle slap, head slap, etc.
• Head slap : Normally associated with aggressive behavior
• Head rise/ Spy hop : The whale raises its head in a vertical stance to look around. It is know as a spy hop when a whale's eye is exposed. If the whale raises its head without exposing its eyes, it is know as a head rise
• Fluke up / fluke down dive : The whale arches its body for a deep dive. The last view is its fluke. This is know as a fluke up dive. A fluke down dive is when a whale is surface travelling and does not need to throw its tail high up at a steep angle.
• Whale Song : A complex composition of song units and phrases sung by male humpbacks
• Head Lunge and inflated head lunge : An aggressive behaviour. The male whales sometimes suck in water to make themselves appear bigger than their rivals. This is known as an inflated head lunge
• Head Butting : An aggressive behaviour
• Tail Cocking : An aggressive behaviour. The whale cocks its tail ready to strike its opponent
• Tail extension : Female whales are sometimes seen with their flukes raised above the surface. This is known as a tail extension and is belived to be a feeding position as calves have often been seen bobbing up beside the fluke occasionally
• Motor boating : An aggressive behavior where the whale raises its head and swims, creating a bow wave resembling a ship ploughing through water
• Boat mugging : Close encounters with whales are more often experienced on calm days. On such occasions, a whale or two may swim around and below a vessel, staying for a certain amount of time to inspect the curious object. This is "affectionately" known by whale watchers as "boat mugging"