Draft:Humpback Whales (megaptera novaeangliae)

Humpback Whale Characteristics

Humpback whales (or megaptera novaeangliae) are one of the most common whales found on the planet. Humpback whales are massive marine animals capable of extraordinary feats of agility. They have vast migrations, traveling more than most other underwater species on Earth to find food and a partner to give birth to their young each year. The underlying reason for their name is their distinct hump located on their backs. Humpback whales are gray and black in color with white undersides. Each humpback whale has two blowholes and the purpose of them is that it allows whales to breathe when they surface from the water. They can hold their breath for about five to ten minutes underwater. Humpback whales are around 46 to 56 feet long and weigh around 44 tons (88,000 pounds). Males are generally larger than females. The flukes (patterns on the tails) are unique and scientists use these patterns to tell one whale apart from another. Another feature that humpback whales have are called barnacles, which are tiny bumps on the head and flippers of the whale. These vary in color and size. A white barnacle can be spotted throughout the humpback whale’s body are called acorn barnacles. An acorn barnacle has a life span of approximately 1 year. These white circles are scars left on the humpback's skin after the barnacles that resided there either died and fell off or were knocked off during breaching or rubbed off when rubbing against other whales. These scars can persist for 10-20 years. When humpback whales sleep, they shut down half of their brain. Being partially awake allows them to continue breathing and be aware of their surroundings. They usually stay in place as they sleep near the surface. As they rest, they are switching which hemisphere of the brain is awake. Just like us, they breathe air, have hair, are warm-blooded, give birth to live young, and feed their calf milk. Humpback whales are extremely active, often slapping their flippers and flukes on the surface of the sea. Humpback whales are famous for breaching and showing their tails when they dive. Whale Contraries

There are many different contraries between blue whales and humpback whales. According to oceanservice.noaa.gov, there are, by far, more humpback whales existing than blue whales. There are 150,000 individual humpbacks left on the planet and only 10,000 blue whales left. These whale numbers have been rebounding since the whale hunts of the 1960’s. The differences continue into the looks of both species of whales. Humpback whales are a bit shorter than blue whales, measuring only 46 to 56 feet. On the other hand, blue whales can grow up to 90 feet long (around 2 school buses). Another difference in appearance is that humpback whales have proportionally long flippers about ⅓ the size of their body, while blue whales have relatively short flippers. Similarly, both whale species have tiny pimple-like bumps on their heads and fins called barnacles. The size and shape of barnacles vary throughout the body. Humpback whales are very intelligent. They have coded different songs to mean different things, such as, when they have found food, an enemy, or a mate, these whales can emit whistling sounds through their blowholes to communicate with one another underwater. Likewise, blue whales can do the same. They can emit low frequency vocalizations, which can travel very long distances. Likewise, both creatures have high intelligence levels.

Intelligence of the Species

Not only are humpback whales extremely intelligent, they also have complex social systems, make tools, and communicate extensively with both songs and social calls. Considered the “acrobats of the ocean”, humpback whales are deep-diving creatures that are both exceedingly playful and endlessly curious. With a brain weighing one ton, these whales demonstrate a high level of intelligence. Humpback whale brains contain specialized brain cells called spindle neurons. These are associated with advanced abilities such as recognizing, remembering, reasoning, communicating, perceiving, adapting to change, problem-solving and understanding. Humpbacks are famous for their breaching - a way of launching themselves out of the water using their tails and slapping the sea with their fins. Scientists believe that these behaviors are forms of communication. For instance, these signals help ward off predators or send messages to other whales. The bigger the splash, the longer the distance their signals carry. Male humpback whales are best known for their deep and bellowing melodies which are intricately coded to share different meanings, depending on the pitch, tone, and volume. According to nathab.com, all of the males in a particular humpback population sing the same song. It’s one that’s completely unique to the population, though the song gradually changes over time. With these series of calls, they are truly, to the core, the “sirens of the sea”.

Feeding Patterns

Humpback whales make bubble nets to catch food. This effort is called bubble-net feeding. It requires a complicated, highly synchronized effort that shows high biological intelligence. One whale usually leads the endeavor, diving deep then rising up to the surface. From deep below, it'll begin to blow air to create bubbles. This confuses and traps the krill above. Krill are zooplankton - small invertebrates that swarm in the ocean near the surface. Although, these whales have another clever method. They stay still in one place and open their gigantic mouths and slowly let the fish swim inside. When it has reached its satisfaction level, the whale will then drain the water from its mouth. Since humpback whales (as well as other species of whales) have baleen plates on the contrary to teeth, they swallow the abundance of krill whole. Then, the whales take a number two. In one bowel movement, they can excrete over 200 liters of poo. Depending on the type of whale and its dinner, feces can be neon yellow to brick red; fleecy in texture to having the consistency of liquid breadcrumbs. Even though whale poop sounds gross, it is actually beneficial to the environment. Whale poop is rich in iron, which is an important micronutrient for ocean creatures. Tiny marine plants called phytoplankton eat the iron, tiny krill eat the plants and whales and fish eat the krill. By feeding on iron-rich krill, in the deep and returning some of that iron to the surface in the form of poop, whales are preserving a crucial element in the food web. The whale's iron-rich feces act like manure on farm fields and gardens, fertilizing nutrition-poor ocean waters. It provides a base for the entire food chain that the rest of the ocean depended on. Excessive whaling might have broken this iron cycle. With less iron at the surface, everything crashes. Furthermore, whale feces not only helps keep the ocean ecosystem in balance, but scientists have recently discovered that it has the added benefit of helping remove excess carbon dioxide from the environment (the cause of global warming and climate change).

The Migration of the Humpbacks

Humpback whales live in all oceans around the world. They travel great distances every year and have one of the longest migrations of any mammal on the planet. Some populations swim 5,000 miles from tropical breeding grounds to colder, more productive feeding grounds. Humpback whales leave Alaska, their feeding grounds in the fall and swim almost non-stop until reaching their breeding grounds in Hawaii, which can take between 6-8 weeks. During the hotter months of the year, from November to May, humpback whales feed in the waters of the Antarctic. They then migrate north to their subtropical breeding grounds off the Queensland coast in Australia. Between May and July, humpback whales start heading north. At about 3,000 miles each way which is why it takes them so long despite their epic size. Since krill isn't found in Hawaiian waters, humpback whales in Hawaii do not eat while here. They eat extra food to ensure that they can survive during the breeding season after the migration to Hawaii. Adults go for months at a time without eating, losing up to one-third of their body weight. After embarking on their journey, they will search extensively for a safe breeding area for the females. The female whales have a gestation period of 10 to 13 months. Most travel 4000-5000 miles twice a year between their breeding and feeding grounds. Breeding and mating are done in warmer climates during the winter. When they arrive, they can weigh as much as one ton, and are generally 3-5m in length. For the first year of their life, they will remain by their mother's side. They nurse on her high-fat milk for at least 5 months and often as long as a year. The baby humpback whale is first born, the mother will gently nudge it to the surface of the water for its first breath.

Changes in the Environment

Humpback whales tend to dwell in Arctic to tropical waters. They live in shallow waters but go deep underwater to hunt for food. Unfortunately, due to global warming, there has not been a sustainable amount of food for these creatures to feed on and their migration routes have been altered. As ocean temperatures rise, whales are migrating earlier and traveling further. Changes in ocean temperatures are critically endangering these animals. Humpback whales think that it is time to migrate when it is really not. "They are changing their migration cycles. They used to arrive here in July. Now we see them in May," said Ecuadorian marine biologist Cristina Castro as she scanned the horizon for more humpback whales, the species she has studied for the past 18 years. Whales are also continuing north beyond the equator, as far as Costa Rica—a behavior never seen before until now. Warmer waters are killing off the supply of krill, the small crustaceans that are whales' main food source in their Arctic feeding grounds. The whales eat several tons a day to fatten up for their journeys. But now, there isn’t enough krill to last them for even three months. Though these creatures jump up and splash around, they aren’t as healthy as they really appear to be. "You can see their bones. They're sick. They have parasites. We never used to see that," said Ecuadorian marine biologist Cristina Castro that appeared on phys.org. These creatures are exhausted from their longer migration routes since climate change which started not so long ago. They have become skinny and have diseases because of these reasons.

History of Whaling

Commercial whaling led to the depletion of most of the world's populations of humpback whales. Humans hunted humpback whales for the purpose of marketing their oil, meat, and whalebone from the 17th to early 20th centuries. Whaling has been an important economic activity in multiple regions throughout human history. Whale oil was highly used to light lamps along with other things as well. For these reasons, the whale oil market was booming. Commercial whaling was conspicuously reduced during the 19th century, due to the development of alternatives to whale oil for lighting, and the dramatic collapse in whale populations. Whales were captured using harpoons with wooden floats attached to long ropes. Once these animals are exhausted from dragging the floats, they would be killed with long lances and towed to shore. Their blubber would be removed and boiled down into oil in large iron vats called try-pots. After the ban in 1986, whaling became illegal, due to the fact that the species were crucially extinct. The United States Congress passed the Marine Mammal Protection Act (MMPA). The Act makes it illegal for any person residing in the United States to kill, hunt, injure, or harass all species of marine mammals (including humpback whales), regardless of their population status. Humpback whales are still hunted in Greenland and by the Bequians of St. Vincent and The Grenadines, for sustenance purposes, but only 1-2 whales are caught per year. In spite of this, Japan, Norway, and Iceland have killed nearly 40,000 large whales since the ban. Over 100,000 dolphins, small whales, and porpoises are also killed in various countries each year. Though, definite efforts have been made to this end. The population numbers of these species have been rebounding ever since the MMPA was passed, so there was some improvement from before. Although, this ban only relates to the US and to no other countries. Currently, many people are supporting the fact that their country should protect the creatures which are on the verge of endangerment. Whaling as an industry began around the 11th Century when the Basques started hunting and trading the products from the northern right whale (now one of the most endangered of the whale species). They were followed first by the Dutch and the British, and later by the Americans, Norwegians and many other nations. The whaling progressed with new technology, which led to the spread of hunting to the Antarctic. Here in Antarctica, there were huge concentrations of feeding whales that made large-scale whaling highly profitable. The First World War provided a large market for explosives using glycerine from whale oil provided by British and Norwegian whaling in the Antarctic. Meanwhile, Japanese whaling had developed separately as a coastal industry, mainly for humpback, right, and gray whales. By 1925, the League of Nations recognized that whales were over-exploited and that there was a need to regulate whaling activities. In 1930, the Bureau of International Whaling Statistics (IWC) was set up in order to keep track of catches. This was followed by the first international regulatory agreement, the Convention for the Regulation of Whaling, which was signed by 22 nations in 1931. However, some of the major whaling nations, including Germany and Japan, did not join and 43,000 whales were slaughtered that same year. Today the IWC has 52 member states, including whaling countries, ex-whaling countries, and countries that have never had whaling industries but joined either to have a voice in the conservation of whales.

Glossary

Acorn barnacle - a stalkless barnacle that attaches itself to a variety of surfaces including rocks, ships, and marine animals

Baleen plates - A bone in the whale’s mouth

Barnacles - A series of bumps on the whale’s mouth and body, they vary in size and color

Breaching - A rise and break through the surface of the water that whales usually perform

Calf - An infant (baby) whale

Commercial whaling - The practice of hunting and killing whales for the purpose of selling and trading their meat and other products derived from them

Flukes - The flat horizontal lobes that form the tail of all whale and dolphin species

Gestation period - The period of time between conception and birth

Harpoon - a barbed missile resembling a spear that is attached to a long rope and thrown by hand or fired from a gun, used for catching whales and other large sea creatures

Lances - a steel-tipped spear carried by mounted knights or light cavalry

Krill - a small shrimplike planktonic crustacean of the open seas, it is eaten by a number of larger animals, notably the baleen whales

Low frequency vocalizations - has long wavelengths, can travel long distances, and has high endurance, whales can emit these kinds of vocalizations

Migration cycles - a natural behavior and component of the life cycle of many species of mobile organisms

Spindle neurons - controls vocalization, facial expression, or autonomic function

“10 Things That Are Amazing About Humpback Whales” Dolphin Safari https://www.dolphinsafari.com

“Do Whales Ever Sleep?” Whale Sense https://whalesense.org

“Facts About Whales” Whale and Dolphin Conservation USA https://us.whales.org.

Graff, Frank. “Whale Poop Makes the Ocean a Better Place” PBS North Carolina https://www.pbsnc.org

“Humpback Whale” NOAA Fisheries https://www.fisheries.noaa.gov

“Whaling” WWF https://wwf.panda.org