Why Do Whales Breach?

Ever wondered why sperm whales breach? This is a question we get asked often by our visitors, so I have put together what is hopefully some helpful information to this interesting question. While our visitors might think the whales are doing this to make for that Kodak moment it is likely they are breaching for other purposes.

Whale Watch Kaikoura tour vessel next to a sperm whale breaching

Sperm whale breaching - Photo Credit: Jaime Brown

Likely theorises for breaching include competitive displays between males (we only have the male sperm whales off the Kaikoura Coastline), it could be a warning of danger coming such as predators in the area. Another theory is that it could be some form of communication – sound travels faster in water than air and it could be a quick way to transmit information to other whales in the area. It has also been suggested that it might be a technique to stun or scare their prey which in turn helps them feed as well as shed loose skin which may be irritating them.

Video of a Sperm Whale breaching

There have been times out on our tours when we have seen first-hand these theories put into practise. I recall one day seeing a sperm whale named Droopy Flukes breach beside our vessel around 20 times, during this amazing display we noticed that he shed a layer of skin going from a dark brown colour to a much lighter shade of brown. While it was a spectacular sight to see I am sure it was also a great feeling for the whale to be rid of that itchy shedding skin. 

Sperm whales are known to eat a lot of squid, squid has beaks which are hard to digest and often end up causing constipation for the whales. We have seen sperm whales breach to relieve them-selves of this discomfort leaving behind evidence of this on the surface... As you can imagine the force and pressure of an 18-20m / 45-55 tonne whale propelling itself out of the water is indeed spectacular and would help relieve this irritation.

Giant Squid Beak

Giant Squid Beak

More recently we have had a couple of humpback whales spend some time in Kaikoura, during their time here they have also been observed breaching rather regularly much to the delight of the passengers and crew alike. Theories around humpback whales breaching are much the same to the sperm whales however with the humpback whales they too maybe trying to get rid of parasites built up on their sensitive skin.

 Whale breaching in Kaikōura, New Zealand

Close-up of humpback whale breaching in Kaikōura, New Zealand

One of the humpback whales that recently visited with us actually had some fishing net caught around it’s long pectoral fin which seemed to have been there for quite some time, this was obviously causing the young whale some distress but eventually after a lot of breaching and slapping of its fin on the water it was able to free itself of this netting.


Humpback whale breaching to get rid of the netting that's caught on its fin

Netting caught on the humpbacks pectoral fin

It really is a blessing to be able to view these beautiful creatures in their natural environment. We never know what to expect from one day to the next when out whale watching so as you can imagine when we do get to see a sperm whale breach (or a humpback whale for that matter) even the crew get very excited to see something so amazing take place. I know some of my fondest memories of my time out on the sea are of those moments when the whales would do something out of the ordinary and take you by complete surprise and leave you with a precious memory of nature at its best.

Sperm whale breaching in Kaikōura. Photo Credit: NZ Whale & Dolphin Trust

Sperm whale breaching - Photo Credit: NZ Whale & Dolphin Trust


Close-up of humpback whale breaching in Kaikōura, New Zealand

Photo Credit: Allan Cronin




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