Why Exactly do Whales Breach?

Mysteries of the Deep

Having an encounter with a humpback or southern right whale in its natural environment is a thrilling experience for any ocean lover. When you see their exhalation in the distance as they surface to breathe, it feels like you’ve hit the jackpot and it’s hard not to get all giddy with delight. The combined anticipation of what is to come is palpable, because one never knows quite what to expect.

Humpback whale breaching
It appears that there are many reasons that whales breach.

The whales may only surface to breathe, and disappear again beneath the surface. They may raise their flukes high up in the air before taking a deep dive or they might slap their pectoral fins repeatedly against the water. All of this is exciting for sure, but what all whale-watchers secretly yearn to see –  is a whale breaching out of the water.

There is something almost spiritual about watching a 20-30-ton creature launching its enormous body out of the water with such grace and power, only to come crashing down against the ocean’s surface with an enormous splash. This above-the-surface spectacle results in a collective gasp from all our guests on board. It is, without a doubt, the ultimate whale-watching encounter.

Angels of the sea.
Humpback whales are often referred to as the angels of the sea.

But have you ever wondered why whales breach? Marine scientists have sought to answer this question for years and although there isn’t one definitive answer, there are several interesting theories. It appears that there are several reasons as to why whales breach, depending on the situation.

One theory is that whales breach in an effort to dislodge those free-riding hitchhikers of the sea – barnacles – from their skin.  Barnacles grow and thrive on the skin of a whale in the cold Antarctic waters, but when the whales migrate to warmer waters, the barnacles tend to die off. Some scientists therefore believe that the breaching could serves to rid the whales of some of these dead barnacles and other annoying parasites.

Southern right whale breaching, Knysna
Southern right whale breaching



Another theory is communication. Recent studies suggest that breaching is a vital form of communication. In some cases, whales seem to breach more frequently in rough seas, which we have also often noticed on our Ocean Odyssey trips. Our Indian Ocean can get quite fierce sometimes and when it does, breaching activity often tends to increase. This is probably due to the fact that they can’t talk to each other underwater quite as well as they do in calm seas.

We have also witnessed an increase in breaching when we encounter mating groups, whereby a series of breaches seems to signal the physical prowess of a particular male when they vying for a single female.

Breaching humpback whale near Knysna
Breaching is a true spectacle

A group of scientists from the University of Queensland in Gatton, Australia once studied 94 different groups of humpback whales migrating south along the Queensland coast in 2010 and 2011.“They spent many hours investigating the potential functions of surface‐active behaviours by examining the social and environmental contexts in which they occurred.” What they deduced is that breaching may play a role in communication between distant groups, because the breaching decreased significantly when whale groups were closer together. The study highlighted the diverse roles of surface‐active behaviours in the communication of migrating humpback whales.

Breaching humpback whale
Could it not be that they are simply jumping for joy??

Personally, I believe that sometimes they do it just for the hell of it. I mean who wouldn’t want to jump – or breach – for joy for no reason whatsoever. It seems clear that these above surface behaviours serve several functions in their complex, social, ocean existence.