The Eschrichtiidae correspond to a family of baleen whales, which currently have a single species, Eschrichtius robustus, and are commonly known as the gray whale. Some studies indicate that it is quite related to other baleen whales, such as fin whales, more than to the whales themselves. This species was on the verge of extinction at the end of the 19th century due to massive hunting, mainly for whale oil. In fact, for many years it was thought to be extinct, until it was re-identified in the 20th century.
These are colossal animals, large in size and capable of migrating over thousands of kilometers in the oceans. Despite the great population recovery, issues such as climate change could affect it today. We invite you to continue reading this PlanèteAnimal sheet in order to be able to document this fabulous marine mammal known as the gray whale.
Origin
- America
- Asia
- Canada
- China
- United States
- Japan
- Mexico
- Russia
Characteristics of the Gray Whale
The gray whale is one of the largest cetaceans in the oceans. The common name refers to its intense gray color; they also have white spots along the body. Another common aspect present on their skin is the presence of parasitic crustaceans, known as whale lice and others called whale barnacles.In addition, in these animals it is common to observe scars, which also turn into a whitish coloring. An adult is between 11 and 15 meters long and weighs 30 to 45 tons.
The gray whale has a narrow, triangular-shaped head that tends to descend and curve into the nostrils above the head. It has broad, shovel-shaped pectoral fins and quite large caudal fins, however, the dorsal fin is seen as a slight pronunciation or small bump. From there and in the caudal direction, species of joints or fleshy bumps are formed that tend to vary from one individual to another. The mouth curves upwards and is rather long, giving the impression that its head is split in two. In contrast, these whales have a beard that usually does not exceed 50 cm and is white to yellowish in color.
Habitat of the gray whale
Currently, the gray whale lives in the oceans of countries such as Canada, China, Japan, Mexico, Russia and the United States.The species is believed to be extinct in Iceland, and in both Koreas. Extinction has been proven in the UK and its presence is uncertain in Vietnam.
Previous data indicates that the current range of this whale is limited to the North Pacific Ocean, generally in the neritic zone (coastal waters) of the countries mentioned. It is important to state that some sightings of gray whales have been documented outside their natural range, as has happened in the Mediterranean Sea (coasts of Israel) and on the coasts of Spain. On the other hand, a stranding has been reported off the coast of El Salvador and one of these whales has been identified in Namibia.
Habits of the gray whale
Although they swim in small groups, these animals are not very social and their main behavioral characteristic is the fact that they constantly migrate at certain times of the year, which makes them one of the marine species with the highest migration rate.They have a habit of lifting half of their body vertically above the water, allowing them to observe their surroundings for about 30 seconds. This is called spyhopping or spy jumping. Also, they can eventually jump out of the water, managing to pull out a body part and falling heavily, splashing a large amount of water.
In general, they usually spend between 6 and 7 months in their hibernation areas and, although a small percentage may stop migrating, most travel long distances on their journeys, indeed these whales are able to travel up to 20,000 km round trip. The usual migratory route allows them to be seen from the coast or at the western coastal areas of Mexico and in areas of the United States such as California, Oregon, Washington, British Columbia and Alaska. Some estimates also indicate that a small group travels between eastern Russia and the Asian coast.However, more accurate satellite-level studies indicate that these groups migrate across the Pacific to hibernation areas in Mexico.
Gray Whale Feeding
Like the whole group of baleen whales, they feed by filtration, that is to say they suck water or mud from the seabed, where they prefer to capture food, then, to Using their tongue, they push the water or mud against the baleen, where the filtration takes place, trapping the animals in these structures, while the watery part is expelled. Among the marine animals that gray whales eat, there is a wide variety of small crustaceans, such as crab larvae, amphipods, krill and mysid shrimp, but also small clams and fish larvae.
These mammals generally feed in the Bering and Chukchi seas, but also along the Pacific coasts adjacent to Canada and the United States.During hibernation, they experience long periods of fasting, during which they feed on the fat they have accumulated. During this period, they can lose up to 30% of their muscle mass. Contrary to what the majority of the population tends to do, it has been identified that a small percentage give up migrating and choose to stay in the feeding area.
The gray whales, when they feed on the bottom, leave a kind of furrows and a large part of the mud that they expel while filtering contains animals that they cannot retain and which the birds benefit from local sailors. A curious aspect that has been detected in a large number of individuals is that when feeding on the seabed, they tend to lean to the right side while sucking up the mud.
Reproduction of the gray whale
As far as reproduction is concerned, cetaceans living in the Eastern Pacific mate and give birth to their young off the coast of California and the Gulf of the same name.Males and females can be with more than one mate during breeding season. The mating season begins in late autumn when their migratory process begins, while births and breeding take place in winter.
In general, a single calf is born in late December or early March, after a gestation period of 11 to 13 months. The mothers maintain a close relationship with their offspring, who feed on highly nutritious milk for about 8 months. The separation of young from their parents usually occurs around the age of 2 years. It is common for mothers and calves to stay fairly close to shore during their migratory journey, most likely to avoid attack by orcas, although the gray whale is capable of dying to defend its offspring from any possible attack.
For more information, we encourage you to read this other article on How do whales reproduce?
Conservation status of gray whales
As we mentioned at the beginning, the gray whale was on the verge of extinction and, although in several regions it has failed to recover, in general the population has recovered, so currently the International Union for Conservation of Nature has listed it as Least Concern. However, some threats still weigh on the species, as accidents with boats have been identified, as well as the trapping of the latter in fish traps, which ends up generating the death of these animals.
It is speculated that another aspect affecting these whales, and which may be the cause of specimens being lost from their usual routes, is climate change, which is affecting ocean temperatures, significantly disrupting the species.
Among conservation measures, the gray whale is subject to various protection programs, such as the International Convention for the Regulation of Whaling.
In general, the oceans are rich in animal diversity and, for centuries, we have been mining it considerably. The Gray Whale is a rare but significant case of the significant recovery of a species from the brink of extinction, showing us that we can take strong action to protect all animals on the planet.