When do gray whales mate

However, this has not been well documented, as fewer studies have focused on this population. A third north Atlantic gray whale population existed as recently as the 's and was described by whalers and colonists in North America, Iceland, Great Britain and Scandinavia. They have since been extirpated from the north Atlantic, likely due to over-hunting by whalers along with other anthropogenic influences e.

Gray whales feed in shallow coastal waters with muddy or sandy bottoms. They are migratory and rely on a variety of coastal habitats. During summer, they stay in waters of up to 60 m in depth and within 0. During fall, eastern gray whales migrate along the west coast of North America and spend winter in waters of less than 4 m in depth. These waters tend to be hyper-saline and are between 15 and 20 degrees C.

Winter calving grounds usually have muddy or sandy bottoms and may contain eelgrass beds or be adjacent to mangrove swamps. Gray whales have mottled gray backs, a trait shared among several mysticete species. They are often hosts to dense infestations of skin parasites e. In gray whales, these parasites often cover the entire body, however, in other baleen whales right whales, Eubalaena australis and humpback whales, Megaptera novaeangliae , infestations are limited to specific areas of the body.

Gray whale calves weigh between kg and kg at birth and are about 4. Adult females are slightly larger than males and are between Males are between Gray whales can weigh as much as 36, kg. Unlike humpback whales Megaptera novaeangliae , with which they are commonly confused, gray whales do not have dorsal fins.

Rather, they have a large hump at the anterior end of the tail stock, followed by 7 to 15 knobs or knuckles of decreasing size. Gray whales have small, paddle-shaped flippers, compared to the large white flippers of humpback whales.

The caudal fin has 2 wide, gray flukes separated by a deep notch. Their upper jaw extends past the lower jaw, and they have 2 to 5 throat pleats, which allow the mouth and throat to expand while feeding.

Adults have to cream-colored baleen plates that are 5 to 25 cm in length. Although little is known of gray whale mating behavior, group mating events of three or more individual have been documented. Gray whales have a high reproductive rate, relative to other baleen whales. Gray whales mate throughout the year, however, most conceptions occur during the fall migration.

After 13 to 14 months of gestation, females give birth to a single calf one occurrence of twin fetuses was reported in , which nurses until it is 6 to 7 months old. Eastern gray whale calves are born in late January in the warm coastal waters of Baja California, Mexico; however, early calving during the fall migration has been documented.

Although less information is available for western gray whales, their winter calving grounds are thought to be along the coast of the South China Sea and likely have characteristics that are similar to the calving grounds of their eastern counterparts.

Calving grounds are typically in shallow lagoons that are less than 4 m in depth and are hyper-saline. Preference for shallow water during calving may have contributed to the extirpation of the north Atlantic population in the mid 's.

Sexual maturation in gray whales occurs around 8 years of age, but has been documented in individuals as young as 5 and as old as Nevertheless, studies suggest that size may be a better indicator of sexual maturity than age. Males average Sixty percent of the population consists of sexually mature adults. The average generation length number of years between an individual's birth and the age at which they give birth for gray whales is 22 years.

Gray whales replenish fat reserves during the summer. Pregnant females are especially dependent on these reserves. From the time they leave the summer feeding grounds in the fall, to when they return in early summer, females rely on fat reserves for energy and milk production.

During times of limited food availability, interval between individual calving events may be extended. Gray whale cows often hold newborn calves to the surface to help them breathe and are fiercely defensive of their young, especially against potential predators such as orcas Orcinus orca and human whalers.

Gray whales inherit their mother's feeding grounds and are often seen, 1 year after they become independent, in their mother's feeding grounds.

Information on the lifespan of gray whales is limited, however, estimates range from 25 to 80 years old. Mortality rates are highest for young gray whales with an average annual calf mortality of 5. Annual adult mortality is estimated to be between 0. Due to their large size and consequent feeding requirements, gray whales cannot be held in captivity. Gray whales prefer to stay close to shore.

As a result, they are one of the more recognizable whale species. They have regular and predictable breathing patterns, exhaling 3 to 5 times from their blowhole, about 15 to 30 seconds apart. Prior to diving, they raise their tail flukes out of the water, after which they may stay submerged for as long as 15 minutes. Individuals may spyhop while looking for predators or fellow whales.

Gray whales often feed close to shore in very shallow waters, which may lead to the appearance of an individual being stranded. Gray whale cows are fiercely protective of their young. Historical accounts of whalers who attempted to exploit their calving lagoons, frequently referred to cows as "Devilfish". They are also referred to as "mussel diggers" for their bottom feeding behavior. Although little is known of their actual home range size, gray whales annually migrate between their polar summer feeding grounds and their temperate to tropical calving grounds.

They have one of the longest migrations of any mammal species, traveling from 16, to 22, km per year. During migration, they swim at a steady speed of 4.

Little is known about perception and communication in gray whales. Most whales communicate using a variety of high and low frequency "whale songs", including prolonged deep moans.

Evidence suggests that gray whales use a simple array of short pulses and moans. Short pulses may be used for basic echolocation. Gray whales are mysticetes i. Newborns are dark gray to black, some may have distinctive white markings, and a calf weighs between 1,, pounds. Babies weigh between 1,, pounds when they are about 15 feet long.

Mating and calving occur mainly in the lagoons of Baja California, Mexico, the shallow, warm lagoons are great nurseries. Calving and mating are sometimes seen during the migration. The warm water helps the calves stay warm until they gain blubber, also the salty water makes the babies more buoyant, so it is easier for them to nurse. It allows the calves to build up a thick layer of blubber, they need blubber for energy to swim during the northward migration, and blubber keeps them warm in the colder waters.

The mother supports her calf at the surface for its first few breaths of air; she then brings the baby up to the surface with her own back and flukes. Calves are usually born in late December to early February in the lagoons of Baja California, Mexico, more than half of the births occur in Laguna Ojo de Liebre. Within about three hours of birth, a calf can keep itself afloat and swim on a steady course, a calf may rest on its mothers back or fins until it becomes a stronger swimmer.

Gray whales feed on small crustaceans such as amphipods, and tube worms found in bottom sediments, they can eat a ton a day of shrimp like amphipods. Gray whales are like cattle on an open range, they travel wherever they can find food. I have seen the resident grays whales off Depoe Bay feed for weeks in one area, then move miles and feed for a month. Since gray whales have no teeth, they capture and strain their baleen, which hangs from the roof of the mouth; grays are the only bottom feeding whales.

When they feed, a whale dives to the bottom, rolls on its right side and gulps mouthfuls of mud from the bottom. As the whale closes its mouth, water and sediments squirt out through the baleen plates. This leaves the amphipods stuck to the baleen inside their mouths. Whales then use their tongues to loosen the amphipods from the baleen, and swallow. Baleen whales have a series of fringed, overlapping baleen plates hanging like curtains from each side of the upper jaw.

Baleen is made of a fingernail-like material called keratin. The plates are off-white and about inch-long. Baleen plates filter water out and trap food in, the baleen is replaced about every 5 years. Gray whales cover about miles a day; they can travel from Unimak Pass in Alaska to Baja California in an average of days. No, some gray whales are found year-round on the coasts of British Columbia, Washington, Oregon, and California.

When do gray whales make their yearly migration? In October, the whales begin to leave their feeding grounds, they swim south during the fall and winter to their mating and calving lagoons in Baja California, Mexico. The southward journey takes around months. The whales return north during the late winter and spring mid-February to early June. There are several reasons; there are fewer hours of daylight, changes in water temperature, and changes in food supply as the northern pack ice increases.

Gray whales travel in groups, first to go south are the pregnant cows, the other adults and juveniles will follow about a month later. When whales head back north the last to leave are the new mothers and calves. The coastline may help them navigate the long distance, and being benthic bottom feeders, they have evolved with an orientation toward the seafloor where their food is located.

While the Blue Whale is known to be the largest species of whale at 96ft. The gray whale received its name from its obvious coloration, gray. Many other names have been ascribed to the gray whale, including desert whale and devil fish. Although, it could be because of their fierce defense they put up when hunted.

During the months of November and December the breeding process begins. Spy hopping a form of cetacean behavior that consists of rising vertically out of the water, head first, and scanning the entire surrounding area while rotating and circling are courtship traditions that take place during early morning hours. By the afternoon time, whales divide into groups of 3 , which consist of 1 female and 2 males. Both males are associated in the mating ritual, but the dominant mate will be identified by extending a single flipper, adhered motionless above the surface of the water as a signaling device.

The female then advances by using graceful contact, grazing the male with her flippers until they both lye belly-to-belly.