Musk ox characteristics, habitat, feeding

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Alexander Pearson
Musk ox characteristics, habitat, feeding

The musk ox (Ovibos moschatus) is a placental mammal belonging to the Bovidae family. One of its distinctive characteristics is the coat, having two types: an external one, which is long and grows continuously; and another on the inside, much shorter and with a look similar to wool.

The horns of the musk ox are present in both sexes. However, in the male they are large, with a broad base, which covers almost the entire forehead. Regarding the shape of these structures, it is similar to that of a pointed hook. Regarding the coloration, the body is gray, brown and black. These shades contrast with the limbs, which are white.

Ovibos moschatus

As part of mating, the male secretes a substance with a strong musky odor. In this way, it attracts females, being able to copulate, in the same reproductive season, with several of these.

When the herd is threatened by a predator, the adults form a circle, surrounding the young. Thus, the horns present a solid front, which is effective against Arctic dogs and wolves. However, it makes them vulnerable to hunters..

Article index

  • 1 Characteristics of the musk ox
    • 1.1 - Size
    • 1.2 - Fur
    • 1.3 - Hooves
    • 1.4 -Smell glands
    • 1.5 - Horns
  • 2 Adaptations to the environment
  • 3 Taxonomy
  • 4 Habitat and distribution
    • 4.1 Reinsertions
    • 4.2 Habitat
  • 5 Playback
    • 5.1 Reproductive control
    • 5.2 The breeding
    • 5.3 Reproductive adaptations to the Arctic environment
  • 6 Food
  • 7 Behavior
  • 8 References¬†

Musk ox characteristics

- Size

The musk ox is sexually dimorphic, the female being smaller than the male. It measures between 200 and 250 centimeters and weighs 272 to 363 kilograms. As for the female, her body has a length of 135 to 200 centimeters, with a weight that ranges from 182 to 227 kilograms..

- Fur

Its coat is thick and long, except for the face, which is short. This gives the animal an appearance of having a large body, which instills fear in predators. The length and abundance of the hair makes the tail hidden and it almost covers the entire ear.

Regarding the coloration it is a mixture of gray, black and brown. These shades contrast with their limbs, which are white.

Types of hairs

Musk Ox (Ovibos moschatus). Source: BS Thurner Hof, CC BY-SA 3.0, via Wikimedia Commons

Like the vast majority of mammals that live in cold climates, the Ovibos moschatus it has long protective hairs, which can measure up to 60 centimeters. Its growth is continuous, being able to reach the ground, in the case of older adults.

These provide an insulating layer against low temperatures. In addition, they act as a barrier against the actions of wind, rain and insects..

On the inside, there is the qiviut, a much shorter coat, which provides additional protection. Its characteristics correspond to those of a soft and light wool. This hair begins its growth in autumn, shedding in the spring.

On the back of the body, the guard hairs are shorter, which reveals a patch of a cream or light brown tone. This is known as the saddle. The adult musk ox usually develops a voluptuous mane at shoulder level.

- Hooves

The helmets of this species are made of keratin and function as snow insulators. They are also used to dig in the ice and gain access to some food. This species has two fingers, on which the entire weight of the body falls.

-Scent glands

Preorbital gland

The musk ox has a preorbital gland. Its shape is similar to a pear and extends between the tear bone and the skin. It is made up of apocrine sweat glands, however, the sebaceous glands are associated with the hair follicles located in the central tube.

The secretion occurs mechanically, when the mammal rubs the gland with its front legs. Also, it can move its head against the bark of a tree, thus stimulating the exit of the substance contained in the organ..

The liquid has a sweet odor and, according to chemical analysis, contains cholesterol, benzaldehyde, two types of saturated gamma-lactones, straight chain and monounsaturated.

The preorbital gland is functional in both males and females, however, in males it is much larger. According to experts, the main function is to be part of the threatening behavior of the musk ox.

Musk oxen (Ovibos moschatus)

In their natural habitat, rubbing of these glands and scent marks occur during fights between males. Also, there is usually liquid segregation when the ox has aggressive encounters with other species..

As for the females and the young, they use the secretion of the gland in interspecific encounters.

Preputial gland

When the dominant male is in heat, he has a strong odor that characterizes him. This is a product of the secretion of the preputial gland. The liquid contains p-cresol, benzoic acid and some saturated straight chain hydrocarbons.

During the male's display of superiority, the foreskin forms a pendulous tube, at the end of which is a group of hairs. Due to the movements carried out by the animals, urine drips from the preputial opening, thus moistening the long fur that covers the belly.

- Horns

The horns are present in both sexes. In males, they are large and heavy, developing large bases that occupy almost the entire forehead of the animal. In an aging adult, it can measure up to 60 centimeters.

The coloring of these structures is cream, with black ends. As for its shape, it is very particular. These grow sideways, starting from the midline of the skull. Then they bend downward, on both sides of the head, to later curve upward at the tips.

In this way, each horn forms a kind of sharp hook. Those that are present in females and youngsters have the same shape and color, but are smaller..

Adaptations to the environment

The Ovibos moschatus lives in Greenland, Canada, and some towns in Alaska. In these regions, during the winter season, the temperature drops significantly. To survive the harsh environment, the body of this animal has undergone some adaptations.

One of these is the thick layer of fatty tissue. During the summer, the musk ox stores a large amount of fat in its body. This fulfills a function of thermal insulation, at the same time that it is an excellent source of energy during winter.

Likewise, the hooves of the extremities are coated with keratin. This favors the use of the front legs to dig in the snow, in search of food..

In this sense, during the winter, this species establishes itself in areas where the snow is shallow, thus reducing the energy expenditure of digging a thick layer of ice to access forage..

Taxonomy

-Animal Kingdom.

-Subkingdom: Bilateria.

-Phylum: Chordate.

-Subfilum: Vertebrate.

-Infrafilum: Gnathostomata.

-Superclass: Tetrapoda.

-Class: Mammal.

-Subclass: Theria.

-Infraclass: Eutheria.

-Order: Artiodactyla.

-Family: Bovidae.

-Subfamily: Caprinae.

-Genus: Ovibos.

-Species: Ovibos moschatus.

Habitat and distribution

Distribution of the musk ox (Ovibos moschatus). In red the natural habitat, in blue the recently introduced population. Source: Worldmap_northern.svg: Gringer (talk) Muskox.png: Masaederivative work: Retired electrician, CC BY-SA 3.0 , via Wikimedia Commons

Previously, musk oxen lived in Asia, northern Europe, Greenland, and North America, including Alaska. By 1800, this species had disappeared from Asia and Europe. During the last years of the 19th century and the first of the 20th century, the population that inhabited Alaska was extinct.

This decline in population was primarily attributed to poaching. However, since then, the Ovibos moschatus it has been successfully reintroduced. That is why, currently, this species is distributed in the arctic regions of northern Canada, Alaska and Greenland..

Reinsertions

Thanks to the actions of national and international organizations, who lead reintegration plans, it is currently located on Nunivak Island, in areas of the northeast, north central and northwest Alaska..

It is also on Nelson Island, the Yukon-Kuskokwim Delta, the Seward Peninsula, and in domestic herds throughout the state. In addition, it is protected in the Arctic National Wildlife Refuge and in the Ivvavik National Park of Yukon.

Likewise, it lives in the Bering National Reserve, in Land Bridge and in the Aulavik National, located in the Northwest Territories. On the other hand, the musk ox has also been introduced in Russia, Norway, Svalbard and Siberia.

Habitat

The natural range of the musk ox includes regions of low rainfall, with shallow layers of snow. The vast majority of populations are located on the tundra, in foraging areas that have been swept away by the wind and where there is less accumulation of snow.

It also tends to live in maritime sub-arctic habitats, in high arctic, and in continental arctic and high arctic. In general, the environment of the Ovibos moschatus it is characterized by a short and variable vegetation growing season, and by a long winter, with low forage availability.

Reproduction

The female musk ox reaches sexual maturity when she is 1 to 4 years old, while the male is able to mate between 3 and 4 years of age..

Generally, the reproduction occurs from the end of August to the month of September. During mating, the dominant male will attempt to bond with all the females in his herd. It competes with other males for reproductive control of the group..

Reproductive control

For this, the males try to intimidate each other, using postures, head movements, roars and depositing their urine on the ground. The best known of these rituals is the head blow. In this, the opponents are located face to face, at a distance of approximately 45 meters.

Then they start a race at a speed of up to 33 or 41 kilometers per hour and collide head-on, horns against horns. This can be repeated 10 to 12 times or until one of the males tires and withdraws. This confrontation rarely has a fatal outcome.

The males that participate in these are between 6 and 8 years old. The older ones don't have enough strength and the younger ones don't have the size to compete. Once dominance is established, the male tries to keep the females together, to defend them..

The brood

After approximately eight months of gestation, the calf is born. Soon after, about 45 minutes after being born, she is on her feet and is breastfed by the mother.

The young man weighs from 9 to 11 kilograms, being able to gain around 0.5 kilograms daily. Although they are born with a woolly layer of qiviut and fat, during the first winter they depend on the heat and the food that the mother provides..

Reproductive adaptations to the arctic environment

In addition to the anatomical characteristics that allow it to live in extremely cold conditions, the Ovibos moschatus presents a single reproductive strategy, based on certain physiological and behavioral traits.

In this sense, the female does not go into heat if her organic condition is poor. Thus, a female with low weight, for example, could not survive the winter as a pregnant woman. In this way, it can regain its organic condition and mate next year..

Because the vast majority of young are born before the snow melts and new forage appears, the female needs to be in good health. Not only for the calf to develop normally, but because for three months you will have to suckle it.

Feeding

Musk Ox (Ovibos moschatus), Greenland. Funete: Hannes Grobe), AWI, CC BY-SA 2.5, via Wikimedia Commons

The musk ox is a widespread herbivore that feeds on a great diversity of plant species, including willows, grasses, and sedges..

Their diet is marked by seasonal variability. Thus, the summer season is characterized by rapid growth of short, high-quality plants. On the contrary, in the months of low temperatures, the thick layer of snow affects the forage, which is also of low quality..

During the summer, the Ovibos moschatus Eat preferably wild plants and soft grasses, rich in nutrients. In this period, there is a remarkable abundance of herbs, so the bolus quickly travels through the digestive tract.

This causes a little assimilation of all nutritional substances, an aspect that is compensated by the large amount of food they eat..

In the colder months of the year, eat willows, roots, dwarf birches, mosses, lichens. As a consequence of the scarcity of food and a decrease in its nutritional value, the digestive process is slower.

In this way, the digestive tract can more efficiently absorb proteins, vitamins and other organic compounds important for the fulfillment of vital functions..

Behaviour

The musk ox lives in herds, which vary in number depending on the season. In the winter they are made up of 12 to 14 animals, while in the summer there are between 8 and 20. This species does not have a defined territory, however, it marks its movements with the secretions of the preorbital gland..

Within the group, males and females have separate hierarchical positions, mainly based on age. In addition, the adult musk ox dominates over the young.

Among the privileges that those with the highest hierarchy have, is having access to the best resources. Thus, in the winter, they can displace subordinates from the grass areas.

This species uses various vocal and behavioral abilities. For example, young people often communicate with each other and with their mothers, performing a kind of dance. On the other hand, to demonstrate dominance, the male hierarch may push, trample or chase the other males of the herd.

The pitch of the bleating tends to decrease as the animal ages. Thus, the adult has deeper vocalizations, which can be heard over long distances. In relation to the calls, there are the growl, the snort and the roars.

References

  1. Wikipedia (2019). Muskox. Recovered from en.wikipedia.org.
  2. Elder, S. (2005). Ovibos moschatus. Animal Diversity. Recovered from animaldiversity.org.
  3. Harmsen (2008). Tundra. Science direct. Recovered from sciencedirect.com.
  4. Rowell J1, Betteridge KJ, Randall GC, Fenwick JC. (1987). Anatomy of the reproductive tract of the female muskox (Ovibos moschatus). Recovered from ncbi.nlm.nih.gov.
  5. Alaska Department of Fish and Game (2019). Muskox (Ovibos moschatus) Recovered from adfg.alaska.gov.
  6. Gunn, A. & Forchhammer, M. (2008). Ovibos moschatus (errata version published in 2016). The IUCN Red List of Threatened Species 2008. Recovered from iucnredlist.org.
  7. Gray, David, Flood, Peter, Rowell, Janice. (2011). The structure and function of muskox preorbital glands. Canadian Journal of Zoology Recovered from researchgate.net.
  8. Peter C. Lent (1988). Ovibos moschatus, The American Society of Mammalogists. Recovered from irma.nps.gov
  9. Valerius Geist. (2019). Musk ox.MAMMAL. Recovered from britannica.com.
  10. Anders Noren (2019). Musk Oxen (Ovibos moschatus). Recovered from wilddocu.de.

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