If you have ever seen a whale leap out of the water, then you know this is one of the most amazing and powerful things you will ever see. The leap is called a breach, and in this article, I look at why whales do this.
Whales breach as a means of communication with other members of their species. Breaching is also used to catch food, remove ectoparasites, stretch, and play. New evidence states that it helps them to hold their breath for longer when diving.
If you want to find out more information on why whales breach, then please read on.
What Is A Breach?
A whale breach is defined in the Encyclopedia of Marine Mammals as ‘an intentional jump from the water in which at least 40% of the animal’s body emerges.’
Breaching is different from other behaviors of whales that you may see, including lunging and porpoising.
Lunging is when less than 40% of the whale emerges from the water and generally happens when the whale is lunge feeding.
Porpoising happens when whales make small leaps while swimming close to the surface. This helps them to reduce drag. Porpoising is normally done by smaller whales, dolphins, and porpoises.
Breaching is defined and can be seen as an intentional jump from the water. Dolphins and porpoises do breach the water, but this is known as leaping.
Some whales breach from different angles. Sperm whales swim vertically up to the water’s surface to breach, whereas right and humpback whales, which can swim in shallow water, will swim horizontally before they breach.
Their head and fluke rise up and then down by using their speed, which allows them to leap out of the water.
Although breaches are defined as 40% of the whale emerging from the water, full breaches are possible. Humpback whales need to reach near their full speed of 8 meters per second to complete a full breach.
Although breaches can occur in many different ways, the sight that most people have seen in the wild, on video, or in photos is a whale twisting to land on its side or back.
Why Do Whales Breach?
The main reason that scientists now believe that whales breach is for communication. It has been studied that more social species breach more often and that breachings occurred more frequently when social activities happen.
Both males and females breach at any time of the year, alone or in groups.
The social structure of whales relies heavily on communication between different members of the same species, so breaching is thought to be a way for them to communicate.
However, the whale’s sound hitting the surface travels far but does not reach the distance their songs do. Other whales would also not be able to see the leap of a whale above the water. Both of these facts go against the idea of breaching being a means of communication with other members of their species.
However, the sound of the whale reentering the water is a true sign of the physical abilities of the whale that has breached. This would signal to other members about the whale’s size and their intentions.
The breach may indicate to other members in the vicinity a display of strength, courtship, aggression, or annoyance.
How Much Energy Does A Breach Cost?
A full breach uses a lot of energy, with about 1% of a whale’s daily resting metabolic expended. Due to the amount of energy used, the message from the whale must be significant.
Do Whales Breach For Food?
Whales will also breach once or many times at both their breeding grounds and their feeding grounds. Whales often follow the lead of other whales and will often copy another whale when they breach.
Breaching has been shown to help whales search for food. By breaching from the water, surrounding fish can be stunned, trapped, herded, or scared, allowing the whale to feed on them once back in the water.
Lobtailing also helps the whale get food, and scientists believe that breaching also causes fish to act similarly.
Breaching To Get Rid Of Ectoparasites
Many species of whale, especially the larger baleen whales, are infested with ectoparasites. Most of the whale species studied that breach is more heavily infested than species of whales that do not breach.
It is believed that breaching helps the whales remove some of the ectoparasites from their bodies; however, whales and dolphins that do not attract many ectoparasites also breach.
Other Reasons Whales Leap Out of the Water
Scientists also believe that breaching can be done for other reasons. When in rough water, whales still have to inhale air and may breach to breathe in water-free air.
It has also been stated that whales may use the breach to stretch their bodies and see above sea level.
Another belief why whales breach is due to play. By leaping into the air, whales, especially smaller, younger whales, may just be imitating their larger parents. Due to the amount of energy expended, it is not believed that adults breach as an act of play.
After more recent research, scientists have come up with another reason why whales breach. As whales dive to great depths, they need to be able to hold their breath for a long time.
The muscle of a whale is rich in a protein that carries oxygen. The protein is called myoglobin, and studies show that high levels play a large part in how long a whale can hold its breath.
By breaching, the muscles are recharged with myoglobin allowing them to dive to great depths.
When Do Whales Breach?
Young whales breach more often than adult whales. Female sperm whales, although larger than the males, breach much more often.
Baleen whales in the North Atlantic breach more when in their feeding grounds than in their breeding grounds. Humpback whales can be seen to breach about seven times as much as they do when feeding than when around the opposite sex.
Different species breach at different times to other whales, and different sections of animals in the same species may breach at different times.
The thought that breaching is a means of communicating is especially true in sperm whales, right whales, and humpback whales when groups are splitting up or merging.
In groups of right and humpback whales, a breach from one whale often causes other whales in the vicinity to also breach. Clusters of whales up to 10 km across have been seen to breach this way.
When male humpbacks finish their song in the Hawaiian islands where they breed, they can often be seen breaching.
Wind speeds also play a part in the breaching habits of whales. Scientists have noticed that with higher wind speeds, breaching occurs more often. However, there is no specific reason for why this happens.
Some whales have been seen to breach almost 200 times in one display, although they can be seen getting physically tired as the breaches are less impressive with less of their bodies exiting the water.
Which Whales Breach?
Although some faster species, such as Sei, Bryde’s, and fin whales, will breach, they do it less often than slower whales, such as humpbacks, bowheads, gray whales, sperm whales, and right whales.
Slower whales live in larger groups than faster, slimmer whales, which is why scientists believe that these whales breach more often.
Humpback whales can often be seen breaching, as can right whales and sperm whales. Humpback whales and sperm whales can sometimes be seen doing belly flops, but some will make a complete breach out of the water.
Blue whales, fin whales, gray whales, sei whales, and minke whales can also be seen breaching.
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