An Overview Of The Humpback Whale
On a planet that’s more than a billion years old, one might think that the biggest animals alive today would probably be apex predators. While this is true, the humpback whale (one of the largest whales in the world) is far from earth’s killing machine. On the contrary, these gentle giants mainly eat small fish and plankton smaller than your fingernails. While some movie adaptations such as Moby Dick portray these massive mammals as aggressive and mindless, humpback whales have been known to swim alongside human divers and even engage in games of chase. Humpback whales are some of the most intelligent mammals to live in the sea and they definitively show this with their complex communications and whale songs. Humpback whales are magnificent animals, but are also endangered and need to be protected.
Humpback whales (also known as Megaptera novaeangliae) start out life with their mothers after 11-12 months in the womb. These whales are from the Animalia kingdom and the mammal class. Since humpback whales are mammals and are viviparous, they do not come from eggs like many of the animals in the sea do. Calves are typically born every 2-3 years, which makes the few babies very valuable to the pod (a group of whales). Newborn calves will be about the length of the mother’s head and slightly pinkish in color. Calves are born tail first to prevent drowning and typically other members of the pod will help the mother by keeping her afloat to breathe as she gives birth. Humpback whales are baleen whales (which means they don’t have teeth) and nurse from their mother’s milk until they are weaned. Each baby drinks about 100 gallons of milk a day. The baby whales actually grow very fast due to their nutritious milk that the mother gives them. As the calf reaches the adolescent stage (typically from 6 to 13 years) it begins to integrate itself with the pod until it reaches sexual maturity. These adolescents will turn from pink to light grey and lengthen up to 20 feet. From ages 14 onwards, humpback whales will mate, migrate, and hunt with their pod, rarely living alone. Male juvenile whales will form their own pods and leave their original pod behind. Female whales also start exploring outside their pod, but they are more likely to return to their original pod. Adult humpback whales “have dark backs, light bellies, pleats on their throats, and a small hump in front of their dorsal fin, leading to the common name of 'humpback.'” (New York Times). Compared to a human, an adult male whale will be as long as a school bus from nose to tail. When it comes to length, however, females are usually longer than males! Males can be as much as 10 feet smaller than their female counterparts. Their Latin name, Megaptera novaeangliae, meaning 'big wing of New England”, refers to their front flippers, which can grow up to 16 feet long. One interesting fact from the Marine Mammal Center remarks about how “Each whale has its own unique pattern on the underside of its tail flukes, which can be used like'fingerprints' to identify individual whales.” It is still unknown about how long a humpback whale will live, but scientists hypothesize that they live anywhere from 48-60 years.
Humpback whales are migrational mammals, which means that they will journey across the world depending on the seasons. These whales can typically be found in shallow coastal areas and coastlines where they have summer feeding grounds near the north and south poles. Humpbacks whales can be found all around the world and typically travel 16,000 miles when migrating. There is not one fixed place where these whales can be found but usually feed during the summer in warmer poles in the northern hemisphere (Alaska and Russia) and during the winter travel to the equator (Hawaii, Mexico, and Southern Asia) to mate and give birth. Additionally, as stated in Wildwhales.org, “It has been proposed that humpback whales may migrate to the tropical areas to avoid killer whale attacks; breeding areas like Hawaii have very few mammal-eating killer whales.” Since humpback whales are baleen whales, they do not eat other whales or large fish. They do not have teeth and instead have plates that hang from their mouths that filter out water from the fish they eat every day. They mainly eat krill, plankton, and shrimp which are found off of the coastal areas they migrate to. Sometimes whales will make what is called a bubble net, where several whales blow bubbles from their blowhole and circle around a shoal of fish in order to trap them in a spiral. Then, another whale will swim down and upwards, opening its mouth, and swallow thousands of small fish in an instant. Their fringed baleen act as a sieve and let the water out of their mouths without loosing any food. After that, the process will be repeated until every whale has eaten. Typically, an adult humpback whale will eat around 4,400-5,500 pounds of krill and small fish a day. This may seem like a scary situation for a human being to be in, but humpback whales actually cannot swallow a person! Their esophaguses are actually so small, that a human would not be physically able to move past their trachea. The whales’ throats are much more adept at swallowing their small prey than any scuba diver that swam too far away from his friends, so there’s no need to worry about recreating Pinocchio.
Although these massive mammals look like a fearsome predator, they are actually far from the top of the food chain. Killer whales are known to attach pods of humpback whales, usually going for small calves and pregnant females. Many adult humpback whales actually bear scars on their fins and tails as a result of these attacks. Sharks are another problem that adult humpback whales have to deal with. More aggressive sharks such as tiger sharks and great white sharks target calves or sick adults. Sharks like these will continue to bite at a whale until it cannot swim. Adult male whales usually can prevent this, with many of these large mammals ramming the attacker until it is fended off or dead. Additionally, there are other predators that threaten the humpback whale, and are one of the main reasons they are endangered. Humans have hunted humpback whales since the early 1800s for their blubber for food and oil for lanterns. From the 17th century to the 20th, humpback whales have been hunted for their oil, meat, and baleen. During the Industrial Revolution, whale oil was even more prized due to its use in building and maintaining new machines. Whale bones were also prized for their use in corsets, knives, and carving. However, although the humpback was one of the five species normally hunted by whalers, it was the least desirable since it sank about half the time after being killed and its baleen was considered useless. Their numbers fell as much as 90% before they were declared endangered in 1966. These whales have since made a comeback, but still are threatened by pollution, discarded fishing nets, collision with ships, and illegal poaching. The humpback whales are still being hunted in places such as Norway, Japan, and Iceland.
One of the humpback whales’ most distinct features is their ability to ‘sing’ underwater. These whales will create their ‘songs’ that can travel for miles in the open ocean. These moans, whistles, and groans are very complex and can repeat and be remembered by the pod even after they have stopped singing. As said in National Geographic, “It is most likely that humpbacks sing to communicate with others and to attract potential mates.” The humpback whales use the songs to ‘speak’ with one another similarly to how dolphins communicate through whistles and clicks. Most of the songs are performed by males, lasting anywhere between 20 minutes and up to hours long. Additionally, humpback whales will periodically perform acrobatics, jumping out of the water, splashing each other, and doing the iconic tail slap as the dive deep underwater. Scientists believe that these activities are another form of communication since the slaps and splashes on the water can be heard for miles around. Humpback whales are very social creatures much like dolphins and monkeys, often accepting new whales to the pod with little aggressive behavior. Another new development for the humpback whales was the possibility of the whales possessing echolocation. Normally, baleen whales do not have the ability to echolocate and even though humpbacks create their complex songs, it was generally assumed that they were not able to echolocate like their peers. However, a recent study has shown that humpback whales produce “Megapclicks”, short clicks and buzzes used to respond to others. With this new data, scientists are now researching more on echolocation, and how the humpback whale may fit into the puzzle.
As humpback whales are known for being one of the most endangered species of whales in the world, it’s no wonder that they get a lot of help from humanitarian organizations. Humpbacks are among the most endangered whales and fewer than 10% of their original population remains. However, in recent years, humpbacks have repopulated exponentially. The current worldwide population is estimated between 35,000-40,000 whales. The Marine Mammal Center is one such organization that has helped humpbacks over the years. They also helped a mother and her calf after they were run over by a pair of boats. Some whale conservations efforts include the Ocean Alliance, a nonprofit organization that promotes the safety and wellbeing of endangered marine life. Others such as Allied Whale and The Whaleman Foundation have committed themselves to researching and ending the market for whale products. The Whaleman Foundation in particular is responsible for is to end commercial whaling and dolphin hunting worldwide while raising awareness of other major threats to dolphins and whales including entanglement in fishing gear, chemical and ocean noise pollution, ship strikes, and climate change. These organizations have put emphasis on the everyday person to do their part in helping the marine life. Additionally, NOAA Fisheries developed a recovery plan in 1991 to identify actions that would protect the species in important breeding and feeding areas. This recovery plan would protect the mating and feeding of humpback whales, making it illegal to fish there, and also create marine parks where diving and recreational swimming is prohibited.