The Giant Sperm Whale
Did you know it is the Giant Sperm Whale that we see off the Kaikōura coastline all year round? Being the largest of the toothed cetaceans they can measure in at up to 20 metres in length and weigh in at around 60 tonne in weight!
There are some amazing facts about the Sperm Whale that are worth sharing, showing you just how truly amazing these creatures are and in turn how incredibly blessed we are to be able to enter into their natural environment.
Due to the large quantities of oil in their bodies, whales are naturally buoyant in water. It is thought that by regulating the temperature of spermaceti oil in their heads, the Sperm Whale can alter its buoyancy. As the whale is exposed to cold air on the surface, the oil cools down forming a solid wax. The wax is denser than water and helps the whale descend beneath the surface.
By pumping blood into the capillaries around the spermaceti melon, the wax is melted back into a buoyant oil, assisting the whale ascend to the surface.
- The Sperm Whale has 2-30 pairs of conical shaped teeth on their bottom jaw. The top jaw has sockets that the bottom teeth slide into when the mouth is closed.
- The Sperm Whale doesn’t use teeth for chewing, but similar to the action of a crocodile, their jaw snaps shut and food is swallowed whole.
- Each tooth of the Sperm Whale can weigh up to 1 kilogram.
- Male Sperm Whales spend the first 8-12 years of their life with the family pod in tropical waters.
- The females of the pod assist the calves for around 2 years until they are confident swimmers.
- When the males reach puberty, at around the age of 10 years, they leave the family pod forming bachelor pods and move to feeding grounds such as off the Kaikōura coast.
- Male Sperm Whales do not mate until this happens; the whales rarely leave the feeding grounds.
- Sperm whales can live for over 70 years.
Where can they be found?
- Sperm Whales are found in all the world’s oceans, usually in submarine canyons of waters deeper than 400 metres.
- Sperm Whales can be viewed off the Kaikōura coast all year round.
- The Kaikōura Canyon is a feeding ground for male Sperm Whales.
- Male Sperm Whales have around 30-40 cms of blubber (fat) surrounding their vital organs. The blubber acts like a wetsuit, insulating the whales from the cold water. The temperature of the water is far too cold for the females as their layer of blubber isn’t as thick.
- Female Sperm Whales usually inhabit the warmer waters near the tropics.
What do they eat?
- Sperm whales feed on large pelagic fish such as Hapuka (Groper), Ling, Tuna, Black Shark, King Fish but their preferred diet is squid.
- The Sperm Whale feeds on many different species of squid, including the exclusive Giant Squid.
- Despite frequent attempts by numerous scientists here in Kaikōura, the Giant Squid has only been viewed alive in its natural habitat off the coast of Japan.
- The Giant Squid grows to an average length of 12 metres, but has been known to grow to lengths of over 18 metres.
As sound waves (clicks) pass through the spermaceti oil, the sound is enhanced and amplified. The Sperm Whale is thought to be one of the world’s loudest animal. It has been recorded at 230 decibels. It is thought that the Sperm Whale can use its sonar not only to locate its prey but to stun or kill its prey.
Inside the Sperm Whales head:
- The Sperm Whale has the largest brain of any living animal. Their brain is approximately the size of a basketball, approximately 7 times larger than the human brain.
- Also inside the Sperm Whale’s head is the spermaceti melon, containing around 2.5 tonnes of oil.
- Once thought to the sperm or semen, hence the name: Sperm Whale
- Once highly sought after for production of candles, cosmetics, lubrication of sewing machines and industrial machinery. Famous for use in Rolls Royce engines and gearboxes and early Apollo space missions.
- Possibly used by Sperm Whales to assist in echo location and/or buoyancy.
- The Sperm Whales off our coastline dive for 40-60 minutes to depths of up to 1000+ metres.
- The Sperm Whale is the deepest diving mammal in the world, diving for over 2 hours and over to 3000 metres.
As you can see these Sperm Whales that we get to see on our tours are truly magnificent creatures!