Sperm Whales are one of the most fascinating and mysterious creatures of the ocean. These magnificent mammals are known for their immense size, remarkable intelligence, and incredible diving abilities. But perhaps one of the most intriguing aspects of the Sperm Whale is its diet.
In this post, we will delve into the underwater world of the Sperm Whale, exploring the secrets of its feeding habits and the ecological impact it has on the ocean’s ecosystems. Join us as we discover the fascinating world of the Sperm Whale’s diet.
Sperm Whale Body Adaptations
Sperm whales are very well adapted to live and hunt in the world’s deepest oceans. Their general appearance consists of a stream-lined, dark body and a more or less squared head. Their eyesight is indeed poor compared to those of humans and other animals, but they substitute this due a perfectly specialized jaw and head.
The Melon – A Powerful Organ!
The head of the sperm whales contains a big adipose tissue, called the melon. Inside this organ there is mainly spermaceti, which is a waxy substance and provided the sperm whale its name. In connection with the melon organ, sperm whales are able to circumvent obstacles and find food even in the dark depths of the ocean.
A Specialized Long Jaw
The long and narrow jaw of sperm whales contributes to this specialized lifestyle as well. In the lower jaw you can find up to 52 teeth while the upper jaw’s teeth rarely break through the gums. However, it’s not just about these small things; also the whole body is adapted to awesome diving capabilities!
Sperm Whale Diving
Dive Depth
The deepest dive ever recorded for a sperm whale has been almost 3 km deep. Humans only can reach these depths with artificial capsules, like submarines. How sperm whales can cope with the enormous pressure down there is still not fully understood.📚 Similar Scientific Articles
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Sperm Whales Dive Cycle
However, we already know a lot about the common dive cycle of this species. After resting at the surface for around 10 minutes sperm whales breathe out one last time and start the deep dive by showing their famous fluke. Then, they will be diving for usually 40-60 minutes, but sometimes longer. The longest recorded dive has lasted almost two hours!
And now you are probably asking yourself what these guys are doing down there for so long?
Sperm Whales Hunting Behavior
As they usually dive down to at least around 600 – 800 meters it is hard to observe for us humans what they are doing all the time. Nevertheless, we got some striking information about their hunting behavior by underwater microphones, also called hydrophones. Using their melon organ, sperm whales can produce the loudest sounds on earth. With up to 233 decibels loud echolocation clicks they are able to find their main food sources without seeing anything.
Besides listening to those clicks, we further gained a lot of knowledge about their food sources by examining the stomach content of stranded individuals. And you will wonder, but this content differs with the location the whale spent most its time!
Sperm Whale Diet
In different seas we also have different animals that can serve as prey for the sperm whales. They need to eat regularly and huge amounts. In order to withstand the harsh environment, sperm whales eat around 3% of their body weight every single day! This makes about one ton of prey on a daily base. That’s a lot! But what do they actually hunt in these huge amounts?
Main Food Source
Usually, sperm whales dive very deep where they predominantly hunt on squids of every size. There are some indications that giant squids may be the favorite prey of sperm whales, although they also do not ignore a small snack squid in between. Giant squids weigh up to one ton and can measure more than 12 meters, so they can feed a sperm whale better than the small-sized squids. However, they also do not give up defenselessly. Several sperm whales can be found with markings around the head, resulting from the desperate fights of the giant squids.
In general, sperm whales eat between 400-800 squids per day, depending on size and hunting success. As squids consist mainly of water and have low energy content, sometimes the whales also substitute with other species they can find in the depths of the oceans.
Additional Food Sources
So besides squid, it is known that in some areas sperm whales hunt on fish, which can make up to half of their prey. Moreover, rays, skates and lobsters are occasionally found in the whales’ stomachs. And interestingly, even sharks seem to be on the menu for those ocean giants!
Most whale species are not able to feed on sharks as they cannot swallow them whole. The throats of other whale species are too thin to swallow a complete shark, but sperm whales make an exception in this. Their throats are much wider and thus, they are capable of swallowing sharks. Some of the sharks, which could be found in the stomachs of sperm whales, have been identified as megamouth sharks, sleeper sharks, basking sharks, blue sharks and even mako sharks!
Threats Connected to the Sperm Whale Diet
Although sperm whales due to their deep diving lifestyle can widely avoid the interference with fishermen, they are still facing quite a few threats and challenges in connection to their diet.
Entanglement & Dragged Gear
Ghost nets and fishing lines are still one of the greatest threats for these amazing animals. They get entangled in floating nets and may swim long distances dragging the attached gear. Fatigue, reduced ability to feed, comprised reproductive success, injuries and even death can be results of these floating dangers.
Depredation
Sperm whales are also known to fish from longline gear from time to time. This behavior is called depredation and can be found particularly in areas susceptible to overfishing and poor marine life. This highly intelligent whale species uses its long jaw to cause tension on the line and thus, shaking the fish off the hook.
Floating nets, plastics and other pollution debris may also occasionally be confused with prey and get ingested by the whales. Studies found different pieces of trash items in the stomachs of sperm whales.
Noise
Moreover, humans cause lots of noises in the oceans. Sperm whales rely on sound to feed and communicate in the water. Although they are the loudest animals, artificially produced noises can cause marine mammals to change frequency and amplitude of their calls, resulting in lower hunting success, decreased foraging behavior, displacement from their preferred habitats and even hearing loss.
Pollution & Climate Change
Furthermore, humans contributed significantly to climate change. Higher temperatures are influencing the habitat of the whales and with this also alter potential food sources in the ocean.
As you can see humans and their pollution are still the biggest threats to sperm whales. Fortunately, at least active whaling ended in most countries around the world, resulting in increasing population sizes.
Sperm Whale Food & The Whale Pump – For a Healthy Environment
Last but not least, sperm whale food or, let’s say what stays after digestion, their feces are an important factor fighting against climate change!
Several studies have shown that the poop of whales helps to stimulate the growth of phytoplankton, which then creates a cleaner and healthier environment by pulling carbon out of the air. This cycle is called whale pump. Estimates state that due to the sperm whales extract about 400.000 tons of carbon from the air every single year!
Moreover, these whales store tons of carbon in their fatty body tissues, which is taken out of the atmosphere for several years. Later when the whales die, they normally sink down to the ground, resulting in a natural carbon sink for hundreds and thousands of years.
Conclusion
In conclusion, the Sperm Whale is a truly remarkable creature, with a diet that is both complex and diverse. From tiny squid to massive giant squid, these whales are capable of hunting a wide variety of prey, which they must consume in large quantities to sustain their massive bodies.
Their diet plays a crucial role in maintaining the delicate balance of the ocean’s ecosystems, and their hunting behavior helps to regulate the populations of their prey. It is through a deeper understanding of the Sperm Whale’s diet that we can continue to unravel the mysteries of these incredible creatures and the role they play in the health of our oceans.
As we continue to explore and study the natural world, let us never forget the importance of these magnificent animals and the crucial role they play in maintaining the health of our planet.
If you want to learn more about these valuable and gentle giants of the deep sea, you can join one of our memorable whale watching tours!
Our knowledgeable team can provide you tons of information about these incredible creatures and why it is so important to raise conservation efforts about them!
Bibliography
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