Sea Cow

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Steller’s Sea Cow Mammal Overview

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Sea cow or better to call it steller’s sea cow is an extremely large underwater mammal that is now extinct. The scientific name for a sea cow is Hydrodamalis gigas. These mammals were first discovered by Arctic explorers and hunters smoothly removed their existence within 30 years from discovery in the 18th century. The animals were mainly found in the Bering Sea near the seashore of the Komandor Islands. Recently, other sirenians like the dugong and manatee are also referred to as steller’s sea cow. However, they are much smaller than the original 18th-century sea cow. A famous naturalist from German by the name of Georg W Steller described the original sea cow’s existence in 1741. He found it during his voyage with Vitus Bering to discover the North Pacific region. The largest sirenian ever known is a sea cow although no specimen exists today. But it is believed that they weighed up to ten metric tons and were about ten meters in length.

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Sea Cow Animal Description

Similar to dugong, the sea cow also had a forked, broad horizontal tail and a comparatively smaller head. To hold across rough sea rocks or move over hard surfaces, their front body had small thickened flippers. Sometimes the skin used to be white spotted or streaked but mostly they had dark brown bark-like skin texture. The vulnerable situation of small animal species is depicted by the sea cow extermination case. The population was 2000 in 1741 while in 1768 there were none. Russian hunters were given sea cows as prized meat for long sea voyages. They usually fall under the animal kingdom and phylum Chordata with class Mammalia. 

Generally, sea cows do not possess teeth but to compact the soft food they have horny mouth plates. Their main source of food was seaweed and kelp found near the seashore or on the ocean’s surface. They were easy hunting targets as most of them used to float on the ocean surface. Submerging ability is what they mostly lacked. The present-day manatee and dugong families all belong to the Sirenia order. Both dugong and the sea cow mammal belong to the same family of Dugongidae and order Sirenia. Only a few sirenians are said to live in cool waters and the steller’s sea cow extinct was one of them. Survival adaptation in cool waters is achieved by the extremely large size of the extinct animal. It provides a much smaller surface area and volume ratio as compared to other tropical sirenians. Better insulation is further provided by the thick hide. 

Ecological Behavior of Steller’s Sea Cow

It is not known whether the animal had any natural predators. But there are possibilities that they were hunted by sharks and killed by whales. But the kelp forests in which they lived must have kept away the sharks. While the killing whales were not able to drown it due to their buoyancy property. It is believed that the young ones were guarded by adults during predation. It is said according to Steller’s documentation, that an ectoparasite used to live on the sea cow’s. But due to the host extinction, all related information was lost. A sirenian was inhabited only by this species of cyamid amphipod. Steller also documented the existence of an ascarid nematode, an endoparasite, living in the sea cows.  

Steller’s Sea Cow Feeding Characteristics

Steller’s sea cow was a strict herbivore just like other sirenian creatures. It used to lift its head every five minutes to breathe and spent the rest of the day eating kelp and ocean surface weeds. As various uncountable species of kelp were its main source of nutrients, it can also be called an algivore. As because it lacked teeth, they mostly fed on soft kelp parts which would be easy to gulp. Hence, the shore used to be filled with heaps of tougher stems of kelp. Seagrass was also a feeding option but it was not an abundant plant that could feed such a large population of sea cow mammal. Another reason for seagrass not being their primary nutrition source is that the plants may have grown too much underwater making it difficult for the sea cows to eat. 

Canopy kelp was grazed by sea cows because it releases comparatively less concentrated toxins as compared to kelp itself. Another reason being, that below 1 meter of the tide, the sea cows had no access to food. The organisms also followed a period of fasting during the winter season due to extremely poor kelp growth. As a result of which they grew thinner during the winter months. Fossils suggest that the population of sea cows in the Pleistocene Aleutian Island was much more than the Commander islands. It might be due to lesser food and unfavourable surviving habitat as compared to the warmer Aleutian lands.

Sea Cow as a Social Being

The sea cow animal is considered to be a highly social being. They were essentially monogamous and helped injured community members to heal. Sea cows lived in small nuclear families and exhibited care of parents by keeping children away from predators. Female sea cows can deliver only one baby at a time as they only have a single set of mammary glands. The mating season was especially during spring as mostly the calves were delivered during autumn of every year. 

Usually, the steller sea cow has four limbs. They are used majorly for eating, walking in low-height water, swimming, defending, and also during copulation. According to Steller’s documentation, it is believed that they used the limbs to anchor or protect themselves whenever strong nearshore waves hit them to stop them from being swept away. It generally moved its tail from one side to another and slowly progressed while grazing on ocean kelp. The vertical beating of the tail usually resulted in rapid and faster motion. After feeding, a characteristic trend seen in them is sleeping on their backs. While sleeping it only made heavy breathing noises like snorting horses otherwise it was mostly mute. 

Sea Cow Uses 

The meat of Steller's sea cow extinct animal was found to be similar to corned beef and even redder, tougher, and tastier as it required more time to cook. The abundant amount of fat is cooked to be used as odourless lamp oil or cooking oil. Steller has described the oil to have a similar taste to almond oil. The thickened leather hides could be used for clothing purposes such as belts and boots or even thin, huge skin boats. The milk of a female sea cow used to be sweet and thick. People made butter out of it or drank it simply like that. 

The bones of such animals were sold at a high price to museums for fossils. Some were sold to make knife handles and other household decorations due to their dense bone structure. Native artisans from Alaska often make handicrafts from this mermaid ivory and selling it in the United States is not illegal as the sea cow is already extinct. However, selling unfossilized bones is illegal and mostly the material is not authentic. Steller’s sea cow has been seen in Rudyard Kipling’s Jungle Book as well as in the 2012 movie, Tales of a sea cow. The extinction of sea cows has been spoken about in Sebald’s Nach der Natur. As far as the current Dugong is concerned, body parts are highly used in decoration, food, and medicines. Tusks are used as sword handles while ribs are used up in carvings. The oil obtained is used as a conditioner and wooden preservatives.

Interaction of Sea Cows with Humans

The reason for the extinction of sea cows are hunters and fur traders. Sea cows could never submerge underwater and remained floating. Hence, they were an easy target for hunters. They were also hunted down for their valuable fat. The hunters used large cables and hooks to drag it to the shallow waters. After dragging it near the shore, other people stabbed it repeatedly with spears until butchered completely. The main challenge here was to bring the animal near shallow waters.

The Aleut people migrated westward to hunt down sea cows as their population was more concentrated near the Aleutian Islands. Possibly it was the main reason for the extinction of the animal in that area. The decline in kelp quantity due to medieval warming could also cause extinction. Sea cows might have also interacted with the Yupik Siberian people, whose main dietary food is marine mammals. It could have been the possible reason for extinction near the St Lawrence Islands. There are plenty of such extinction reasons due to human interaction but these are some of the major ones.

FAQ (Frequently Asked Questions)

1. What are Some of the Folklores Associated with Dugong – The Evolved Sea Cow?

Answer: Dugong is the present-day evolved version of the 18th-century steller’s sea cow after extinction. Many folklores are associated with the existence of dugong in various parts of the world. In Thailand, it is believed that teardrops of a Dugong form a strong Love potion that can lure people. In parts of Indonesia, people consider them as women who are reincarnated after death. Many areas of the Philippines use parts of the dugong’s body to distract away evil spirits. It is thought that they will bring bad luck to the family. Again, Dugongs are seen as pillars of strength and endurance in Papua New Guinea. There are many other stories about the ancient sea cow in various other literature sources. But these superstitions still prevail.

2. What Does a Steller's Sea Cow Look Like?

Answer: The sea cow animal grew up to thirty feet and were huge creatures. The large size was basically to reduce the surface area and volume ratio, make it capable to live in low temperature, and conserve body heat. It had an extremely rough outer skin so that it can glide through rough rocky surfaces. The sea cows never submerged properly due to positive buoyancy. The blubber was also thick to adapt to the tough climates of the Bering Sea. The tail was forked and forelimbs were rough and long allowing movement through rough tides. The skin was usually blackish dark brown with white spots sometimes. As compared to the entire body, the head looked smaller. The upper lip was broad and large so much that the mouth appeared below the skull.

3. What is the Internal Organ Structure of a Sea Cow?

Answer: Halfway between the ears and nostrils, sea cows had small eyes with black iris and no lashes. The mouth had a small tongue that could not reach the chewing pads. The spine is supposed to have seven cervical, three lumbar, seventeen thoracic, and thirty-four tail vertebrae. The ribs were extremely large. It had a fan-shaped scapula becoming narrower near the neck and broader near the posterior region. The bones were both dense and bulky. The full intestinal tract length was about 500 feet. It had a wide bile duct but no gall bladder in specific. The stomach measured almost 6 feet by 5 feet while the size of the heart was huge. The weight of the heart was approximately 16 kilograms.

4. How Were Sea Cows Discovered?

Answer: One of the most common questions is what is a sea cow called. The sea cow was first discovered by Georg Wilhelm Steller who came from Germany for the North Pacific Expedition back in 1741. It is because of the same that even today the animal is known as steller’s sea cow. He was shipwrecked and lived in the Bering Sea forests for about a year. His work, The Beasts of the Sea, was published in 1751 from where we get an ample amount of information regarding sea cows. For years after years, no bones or remains of sea cows were discovered until the 1840s when the first sea cow skull was discovered. Maximum bones were unearthed during the 19th century. By 2006, almost 25 complete skeletons were unearthed. Even now, sea cow bones are found near the Commander Islands. But finding an entire skeleton is extremely difficult. In 2017, a new skeleton was discovered with major bones present but still some missing.