The humpback whale is an animal that can reach 15 meters and weigh up to 40 tons.Every year, large groups of humpback whales ( Megaptera novaeanglie ) arrive from Antarctica to the Brazilian coast with the intention of breeding in warmer waters. Found on the Brazilian coast from Rio Grande do Sul to Pará, they are found in greater numbers in places between southern Bahia and northern Espirito Santo, in a region known as Banco dos Abrolhos. It is believed that about 11 thousand humpback whales visit the Brazilian coast all year round.
An adult humpback whale reaches an average of 15 meters in length and its weight can reach 40 tons. Your puppy can be born 4 meters long and its weight can reach 1.5 tons. This animal, found in all the world’s oceans, has a life expectancy of around 60 years.
These whales feed on small crustaceans called krill. For a long time, it was believed that they did not eat during the reproductive phase, but lived on their fat reserve until they reached the feeding area. However, some recent research has shown that some do a dive up to approximately 300m in depth. This may indicate that even during the reproduction phase, they descend to feed quickly. Another hypothesis is that they are communicating, since the propagation of the sound is better in the depths.
Humpback whales have great strategies for feeding. A common behavior among them is the formation of groups that initiate the release of air near a school of krill. When they release air, they form a kind of bubble layer that prevents the school from escaping. They then fill the mouth with water with krill and, subsequently, eliminate the water by the fins, leaving only the small crustacean in your mouth, a kind of filtration. Some whales also feed by making a very loud sound or hitting their tail in the water, which ends up confusing the school.
During the reproduction phase, it is common to observe the singing of the males. It is believed that he sings to attract females and who knows how to keep some competitors away. Each population presents a different corner, being a way to differentiate them.
The gestation of these animals lasts about 12 months and usually only one baby is born. After birth, they wait a certain period of time for the puppy to be able to migrate to the area where they feed. During this period, the newborn increases its fat layer, which is essential to survive in the icy waters of Antarctica.
An interesting behavior of the humpback is the jump. She can project more than half of her body out of the water. It is not yet known what the real reason for this behavior is, but some hypotheses are raised. Some authors suggest that it may be a communication strategy, others claim that it is a way to eliminate some parasites, among other hypotheses.
Whales, like us, have in their bodies a characteristic that allows them to be distinguished from each other. The caudal fins of these animals have unique details for each individual, as well as our fingerprints.
These whales were the target of indiscriminate hunting for many years. This fact caused a great decrease in the population of humpback whales around the world, which led the authorities to ban hunting in 1966. After the ban, the population grew again, but it is still considered a vulnerable species according to the IUCN (International Union for the Conservation of Nature).
Whales, even after the hunting ban, face problems caused by humans. It is common to find animals injured due to being run over by boats and being caught in fishing nets accidentally. These injuries usually cause these mammals to die. It is also believed that ecological tourism can disrupt the lives of these animals, since boats with tourists cause breastfeeding to be stopped
In addition to human beings, among the main causes of mortality of humpbacks, we can highlight the attack of orcas and sharks, as well as the separation of young during breastfeeding, diseases and old age.
Worth knowing! In Brazil, we have the Humpback Whale Project , which has as its main objective the protection of these animals. In addition, the Project helps in research regarding the behavior of this species.