Steller's sea cow (
Hydrodamalis gigas) is a large extinct
sireniaSirenia is an order of fully aquatic, herbivorous mammals that inhabit swamps, rivers, estuaries, marine wetlands, and coastal marine waters. Four species are living, in two families and genera. These are the dugong and manatees...
n
mammalMammals are a class of vertebrate animals whose females are characterized by the possession of mammary glands while both males and females are characterized by sweat glands, hair, three middle ear bones used in hearing, and a neocortex region in the brain.Mammals are divided into three main...
. Formerly abundant throughout the North Pacific, its range was limited to a single, isolated population on the uninhabited Commander Islands by 1741 when it was first described by
Georg Wilhelm StellerGeorg Wilhelm Steller was a German botanist, zoologist, physician and explorer, who worked in Russia and present-day Alaska.-Biography:...
, chief naturalist on an expedition led by explorer
Vitus BeringVitus Jonassen Bering was a Danish navigator in the service of the Russian Navy, a captain-komandor known among the Russian sailors as Ivan Ivanovich...
. Within 27 years of discovery by Europeans, the slow moving and easily captured Steller's sea cow was hunted to extinction.
The sea cow grew at least long, much larger than the
manateeManatees are large, fully aquatic marine mammals sometimes known as sea cows. They are noted for their rather friendly nature, large size and paddle-like flippers. The name manatí comes from the Taíno, a pre-Columbian people of the Caribbean, meaning "breast"...
or
dugongThe dugong is a large marine mammal which, together with the manatees, is one of four living species of the order Sirenia. It is the only living representative of the once-diverse family Dugongidae; its closest modern relative, Steller's Sea Cow , was hunted to extinction in the 18th century...
.
Steller's sea cow (
Hydrodamalis gigas) is a large extinct
sireniaSirenia is an order of fully aquatic, herbivorous mammals that inhabit swamps, rivers, estuaries, marine wetlands, and coastal marine waters. Four species are living, in two families and genera. These are the dugong and manatees...
n
mammalMammals are a class of vertebrate animals whose females are characterized by the possession of mammary glands while both males and females are characterized by sweat glands, hair, three middle ear bones used in hearing, and a neocortex region in the brain.Mammals are divided into three main...
. Formerly abundant throughout the North Pacific, its range was limited to a single, isolated population on the uninhabited Commander Islands by 1741 when it was first described by
Georg Wilhelm StellerGeorg Wilhelm Steller was a German botanist, zoologist, physician and explorer, who worked in Russia and present-day Alaska.-Biography:...
, chief naturalist on an expedition led by explorer
Vitus BeringVitus Jonassen Bering was a Danish navigator in the service of the Russian Navy, a captain-komandor known among the Russian sailors as Ivan Ivanovich...
. Within 27 years of discovery by Europeans, the slow moving and easily captured Steller's sea cow was hunted to extinction.
Description
The sea cow grew at least long, much larger than the
manateeManatees are large, fully aquatic marine mammals sometimes known as sea cows. They are noted for their rather friendly nature, large size and paddle-like flippers. The name manatí comes from the Taíno, a pre-Columbian people of the Caribbean, meaning "breast"...
or
dugongThe dugong is a large marine mammal which, together with the manatees, is one of four living species of the order Sirenia. It is the only living representative of the once-diverse family Dugongidae; its closest modern relative, Steller's Sea Cow , was hunted to extinction in the 18th century...
. Steller's work contains two contradictory weights: 4 and 24.3 tons. The true value probably lies between these figures, around 8-10 tons. It looked somewhat like a large seal, but had two stout forelimbs and a
whaleWhale is the common name for marine mammals of the order Cetacea. The term whale is sometimes used to refer to all cetaceans, but in more common English usage it generally excludes the members of the Delphinoidea superfamily, such as dolphins and porpoises...
-like tail. According to Steller, "The animal never comes out on shore, but always lives in the water. Its skin is black and thick, like the bark of an old
oakAn oak is a tree or shrub in the genus Quercus , of which about 400 species exist. "Oak" may also appear in the names of species in related genera, notably Lithocarpus...
…, its head in proportion to the body is small…, it has no teeth, but only two flat white bones—one above, the other below". It was completely tame, according to Steller. They fed on a variety of
kelp{Taxobox| name =Kelp| image = Kelp In Freycinet Tasmania.jpg| image_width = 300px| image_caption = Kelp on rocky beach in Freycinet, Tasmania| regnum = Chromalveolata| phylum = Heterokontophyta| classis = Phaeophyceae| ordo = Laminariales...
. Wherever sea cows had been feeding, heaps of stalks and roots of kelp were washed ashore. The sea cow was also a slow swimmer and apparently was unable to submerge.
Population and extinction
The population of sea cows was small and limited in range when Steller first described them. Steller said they were numerous and found in herds, but zoologist
Leonhard Hess StejnegerLeonhard Hess Stejneger was an American ornithologist, herpetologist and zoologist. Stejneger specialized in vertebrate natural history studies. He gained his greatest reputation with reptiles and amphibians....
later estimated that at discovery there had been less than 1,500 remaining, and thus had been in immediate danger of extinction from overhunting by humans. They were quickly wiped out by the sailors, seal hunters, and
fur tradeThe fur trade is a worldwide industry dealing in the acquisition and sale of animal fur.-Russian fur trade:Before the colonization of the Americas, Russia was a major supplier of fur-pelts to Western Europe and parts of Asia. Fur was a major Russian export as trade developed in the early Middle...
rs that followed
BeringVitus Jonassen Bering was a Danish navigator in the service of the Russian Navy, a captain-komandor known among the Russian sailors as Ivan Ivanovich...
's route past the islands to
AlaskaAlaska is the largest state of the United States of America by area; it is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...
, who hunted them both for food and for their skins, which were used to make boats. They were also hunted for their valuable subcutaneous fat, which was not only used for food (usually as a
butterButter is a dairy product made by churning fresh or fermented cream or milk. It is generally used as a spread and a condiment, as well as in cooking applications such as baking, sauce making, and frying...
substitute), but also for
oil lampAn oil lamp is a simple vessel used to produce light continuously for a period of time from an oil-based fuel source. The use of oil lamps commences from prehistory and extends to the present day....
s because it did not give off any smoke or odor and could be kept for a long time in warm weather without spoiling. By 1768, 27 years after it had been discovered by Europeans, Steller's sea cow was extinct.
Fossils indicate that Steller's sea cow was formerly widespread along the North Pacific coast, reaching south to
Japanis an island country in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, People's Republic of China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
and
CaliforniaCalifornia is the most populous state in the United States, and the third largest by area. California is the second most populous sub-national entity in the Americas, behind only São Paulo, Brazil...
. Given the rapidity with which its last population was eliminated, it is likely that aboriginal hunting caused its extinction over the rest of its original range (aboriginal peoples apparently never inhabited the Commander Islands).
It has been argued that the sea cow's decline may have also been an indirect response to the harvest of
sea otterThe sea otter is a marine mammal native to the coasts of the northern and eastern North Pacific Ocean. Adult sea otters typically weigh between 14 and 45 kg , making them the heaviest members of the weasel family, but among the smallest marine mammals...
s by aboriginal people from the inland areas. With the otters reduced, the population of
sea urchinSea urchins or urchins are small, spiny, globular animals that compose part of class Echinoidea. They are found in oceans all over the world. Their shell, or "test", is round and spiny, typically from 3 to 10 cm across. Common colors include black and dull shades of green, olive, brown, purple,...
s would have increased and reduced availability of algae, the Steller's Sea Cow's primary source of food. Thus, aboriginal hunting of both species may have contributed to the sea cow's disappearance from continental shorelines. However, in historic times aboriginal hunting had depleted sea otter populations only in localized areas. The sea cow would have been easy prey for aboriginal hunters, who would likely have exterminated accessible populations with or without simultaneous otter hunting. In any event, the sea cow was limited to coastal areas off islands without a human population by the time Bering arrived, and was already endangered.
In literature
Sea cows appear in
Rudyard KiplingRudyard Kipling was a British author and poet. Born in Bombay, British India, he is best known for his works of fiction The Jungle Book , Kim , many short stories, including The Man Who Would Be King ; and his poems, including...
's short story "The White Seal", where they show the title character a place of refuge from human hunters. Kipling probably knew (a) that the sea cow was considered extinct and that (b) nevertheless people sometimes claimed to have seen them. Thus, his suggestion is that they are around, but mostly hiding.
In
Jules VerneJules Gabriel Verne was a French author who helped pioneer the science-fiction genre. He is best known for his novels A Journey to the Center of the Earth , From the Earth to the Moon , Twenty Thousand Leagues under the Sea , Around the World in Eighty Days and The Mysterious Island...
's 1870 novel
20000 Leagues Under the Sea, the travelers in
Captain NemoCaptain Nemo is a fictional character featured in Jules Verne's novels Twenty Thousand Leagues Under the Sea and The Mysterious Island . Nemo, one of the most famous Anti-heroes in fiction, is a mysterious figure. He is a scientific genius who roams the depths of the sea in his submarine, the...
's fictional submarine
NautilusThe Nautilus is the fictional submarine featured in Jules Verne's novels Twenty Thousand Leagues Under the Sea and The Mysterious Island . Verne named the Nautilus after Robert Fulton's real-life submarine Nautilus...
encounter various sirenians during their journey.
On February 10 they encounter a female
dugongThe dugong is a large marine mammal which, together with the manatees, is one of four living species of the order Sirenia. It is the only living representative of the once-diverse family Dugongidae; its closest modern relative, Steller's Sea Cow , was hunted to extinction in the 18th century...
in the
Red SeaThe Red Sea is a seawater inlet of the Indian Ocean, lying between Africa and Asia. The connection to the ocean is in the south through the Bab el Mandeb strait and the Gulf of Aden. In the north, there is the Sinai Peninsula, the Gulf of Aqaba, and the Gulf of Suez,...
; Nemo states that hunting has made sirenians scarce, yet Ned Land harpoons the animal to eat. It is described as over 7 m long with a mass of 5000 kg (a size far excessive for a dugong in that habitat, though appropriate for Steller's sea cow, found in colder northern waters but already by then extinct for a century).
On April 12, observing a group of
West Indian ManateeThe West Indian Manatee is a manatee, and the largest surviving member of the aquatic mammal order Sirenia .The West Indian Manatee, Trichechus manatus, is a species distinct from the Amazonian Manatee, T. inunguis, and the West African Manatee, T. senegalensis...
s off
Dutch GuianaSuriname , officially the Republic of Suriname, is a country in northern South America....
, Professor Arronax extols their ecological value.
Thus, environmental themes were expressed in Verne's writing; though some details may be inexact, this book has likely contributed to a wider public awareness of marine biology and interest in conservation.
In the contemporary literature, Steller's sea cow appears in a book of poetry
Species Evanescens by Russian poet Andrei Bronnikov. In this book the poet compares the fate of the exterminated animal with the fate of its discoverer. The book examines the personality of Georg Steller and depicts the Kamchatka expedition during which the discovery of the Steller's sea cow had been made.
See also
- Extinction
In biology and ecology, extinction is the end of an organism or group of taxa. The moment of extinction is generally considered to be the death of the last individual of that species...
- List of extinct animals
- List of extinct animals of North America
- Sirenia
Sirenia is an order of fully aquatic, herbivorous mammals that inhabit swamps, rivers, estuaries, marine wetlands, and coastal marine waters. Four species are living, in two families and genera. These are the dugong and manatees...
- Evolution of sirenians
Sirenia is the order of placental mammals which comprise modern "sea cows" and their extinct relatives. They are the only extant herbivorous marine mammals and the only group of herbivorous mammals to have become completely aquatic. Sirenians are thought to have a 50-million-year-old fossil record...
External links