Since it is located directly under the skin, this reserve is easily accessible. Its fat cells are filled and emptied in accordance with the energy needs of the individual. Fasting allows the humpback to dedicate all of its energy to its marathon migration and its reproductive activities.
While the warm Caribbean waters are ideal for breeding or calving, the food they contain is not as rich as the krill or capelin found in the St. Feeding in this region is therefore not worth the effort for the humpback: the energy expended foraging would be greater than the yield of its intake! After giving birth, females continue their fast. This is believed to allow them to prioritize nursing their calf, thereby allowing the latter to grow very quickly in a short period.
Furthermore, fasting is thought to be conducive to converting their fat reserves into fats more easily digested by their offspring. This element plays a key role in species that fast for long periods: it acts as an appetite suppressant and helps break down fat.
In , researchers reportedly detected leptin in one of the deepest layers of blubber of bowhead whales and belugas. They observed the highest levels of leptin in fall, when the members of these two Arctic species were getting ready to migrate, and therefore to fast. The rare sighting gave delighted onlookers the chance see the whale, one of the biggest and fastest in the world, flying through the air in a spectacular show.
Fin whales are quite rare and it's very unusual to see one in their natural habitat, let alone having a personal dance party. The fin whale breached the water three times that means it jumped out of the water then dived back in, kinda like whale dancing. Three times! The two lead authors on the study first proposed in that skin molt could drive the migration for certain Antarctic killer whales.
With new data, they now propose the same for all Antarctic killer whales and possibly all whales that migrate to the tropics. Over eight years, scientists deployed 62 satellite tags on killer whales.
They found that all four types that feed in frigid Antarctic waters migrated as far as 11, kilometers almost 7, miles round trip. Most migrations were fast, non-stop, and largely straight north and back. One whale completed two such migrations in 5.
Researchers also photographed newborn killer whale calves in Antarctica, indicating the whales don't need to migrate to warmer waters to give birth. They suggest that larger whales that migrate to the tropics to molt may have begun giving birth in those same warmer waters. The warm water could speed the growth of calves in an environment with far fewer killer whales, their main predator.
Much like humans, whales and dolphins normally shed outer skin cells continuously. Scientists observed that whales in frigid Antarctic waters are often discolored by a thick yellow film of microscopic diatoms. This indicated that they were not experiencing their normal, "self-cleaning" skin molt. Early whalers referred to blue whales with a heavy coating of diatoms on their white bellies as "sulfur-bottoms.
When whales shed their skin, they also shed the diatoms. The blue whale is a marine mammal belonging to the suborder of baleen whales called Mysticeti. At up to Blue whales can reach speeds of 50 kilometres per hour 31 mph over short bursts, usually when interacting with other whales, but 20 kilometres per hour 12 mph is a more typical traveling speed.
0コメント