Steller's sea cow

Page protected with pending changes
Source: Wikipedia, the free encyclopedia.
Not to be confused with Steller sea lion.

Steller's sea cow
Temporal range: Pleistocene– C. E. 1768
The skull has a large hole on the snout and large eye sockets on either side and flattens out on the top. The ribcage extends half of the specimen's length, and the rest is vertebrae. There are no leg bones, and the scapula overlaps the front half of the ribcage. The elbow is bent back, with the forearms outstretched towards the direction of the head.
Skeleton at the Finnish Museum of Natural History

Extinct (1768)  (IUCN 3.1)[1]
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Sirenia
Family: Dugongidae
Genus: †Hydrodamalis
Species:
†H. gigas
Binomial name
†Hydrodamalis gigas
(
Zimmermann
, 1780)
The triangular Kamchatka Peninsula is to the left, and on the right half are the small Bering Island, which is rectangular and slanted left, and Copper Island, which is also rectangular and slanted left but smaller than Bering Island.
Map showing the position of the Commander Islands to the east of Kamchatka. The larger island to the west is Bering Island; the smaller island to the east is Copper Island.
Synonyms[2][3][4][5]
List of synonyms
    • Hydrodamalis
    • Rytina
    • Manati
      • M. gigas
        Zimmermann
        , 1780
      • M. balaenurus Boddaert, 1785
      • M. borealis Link, 1795
    • Trichechus
      • T. manatus borealis Gmelin, 1788
      • T. borealis Shaw, 1800
    • Sirene
      • S. borealis Link, 1794
    • Nepus
      • N. stelleri Fischer, 1814
    • Stellerus
    • Haligyna
    • Manatus
      • M. gigas Lucas, 1891

Steller's sea cow (Hydrodamalis gigas) is an

epoch, and likely contracted to such an extreme degree due to the glacial cycle. It is possible indigenous populations interacted with the animal before Europeans. Steller first encountered it on Vitus Bering's Great Northern Expedition when the crew became shipwrecked on Bering Island
. Much of what is known about its behavior comes from Steller's observations on the island, documented in his posthumous publication On the Beasts of the Sea. Within 27 years of its discovery by Europeans, the slow-moving and easily-caught mammal was hunted into extinction for its meat, fat, and hide.

Some 18th-century adults would have reached weights of 8–10 t (8.8–11.0 short tons) and lengths up to 9 m (30 ft). It was a member of the family

social animal living in small family groups and raising its young
, similar to modern sirenians.

Description

The skull has a hole on the snout and large eye sockets on either side and flattens out on the top; no teeth are visible.
The skull of a Steller's sea cow, Natural History Museum of London

Steller's sea cows are reported to have grown to 8 to 9 m (26 to 30 ft) long as adults, much larger than

epoch, along with baleen whales and some few toothed whales,[11] and was likely an adaptation to reduce its surface-area to volume ratio and conserve heat.[12]

Unlike other sirenians, Steller's sea cow was positively

parasites. This rough texture led to the animal being nicknamed the "bark animal". Hair on its body was sparse, but the insides of the sea cow's flippers were covered in bristles.[5] The fore limbs were roughly 67 cm (26 in) long, and the tail fluke was forked.[5]

The sea cow's head was small and short in comparison to its huge body. The animal's upper lip was large and broad, extending so far beyond the lower jaw that the mouth appeared to be located underneath the skull. Unlike other sirenians, Steller's sea cow was toothless and instead had a dense array of interlacing white bristles on its upper lip. The bristles were about 3.8 cm (1.5 in) in length and were used to tear seaweed stalks and hold food.[5] The sea cow also had two keratinous plates, called ceratodontes, located on its palate and mandible, used for chewing.[15][16] According to Steller, these plates (or "masticatory pads") were held together by interdental papillae, a part of the gums, and had many small holes containing nerves and arteries.[5]

Side view of a brown-green dugong: It is similar to a manatee in that the head is pointed downwards, the eyes are small, and the body is stocky. The arms are perpendicular to the body and bend backwards toward the tail. There are no fingernails. The tail is knotched, much like a dolphin tail.
Model in the Natural History Museum, London

As with all sirenians, the sea cow's snout pointed downwards, which allowed it to better grasp kelp. The sea cow's nostrils were roughly 5 cm (2 in) long and wide. In addition to those within its mouth, the sea cow also had stiff bristles 10–12.7 cm (3.9–5.0 in) long protruding from its muzzle.[12][5] Steller's sea cow had small eyes located halfway between its nostrils and ears with black irises, livid eyeballs, and canthi which were not externally visible. The animal had no eyelashes, but like other diving creatures such as sea otters, Steller's sea cow had a nictitating membrane, which covered its eyes to prevent injury while feeding. The tongue was small and remained in the back of the mouth, unable to reach the masticatory (chewing) pads.[12][5]

The sea cow's spine is believed to have had seven

phalanges (finger bones), Steller's sea cow possibly did not have a manus at all.[18]

The sea cow's heart was 16 kg (35 lb) in weight; its stomach measured 1.8 m (6 ft) long and 1.5 m (5 ft) wide. The full length of its

intestinal tract was about 151 m (500 ft), equaling more than 20 times the animal's length. The sea cow had no gallbladder, but did have a wide common bile duct. Its anus was 10 cm (0.33 ft) in width, with its feces resembling those of horses. The male's penis was 80 cm (2.6 ft) long.[5] Genetic evidence indicates convergent evolution with other marine mammals of genes related to metabolic and immune function, including leptin associated with energy homeostasis and reproductive regulation.[19]

Ecology and behavior

Two large, oval-shaped plates haveh a ridge running down the middle, and grooves run diagonally from either side of the ridge. Many bristles of varying sizes and widths occur, but all are stiff at the base and taper out at the end. The several small rectangular teeth have numerous holes in them.
Illustrations of the dentition of Steller's sea cow by Johann Christian Daniel von Schreber, mid-1800s

Whether Steller's sea cow had any natural

killer whales and sharks, though its buoyancy may have made it difficult for killer whales to drown, and the rocky kelp forests in which the sea cow lived may have deterred sharks. According to Steller, the adults guarded the young from predators.[6]

Steller described an

endoparasite in the sea cows, which was likely an ascarid nematode.[15]

Like other sirenians, Steller's sea cow was an obligate

Laminaria saccharina, Nereocyctis luetkeana, and Thalassiophyllum clathrus. Steller's sea cow only fed directly on the soft parts of the kelp, which caused the tougher stem and holdfast to wash up on the shore in heaps. The sea cow may have also fed on seagrass, but the plant was not common enough to support a viable population and could not have been the sea cow's primary food source. Further, the available seagrasses in the sea cow's range (Phyllospadix spp. and Zostera marina) may have grown too deep underwater or been too tough for the animal to consume. Since the sea cow floated, it likely fed on canopy kelp, as it is believed to have only had access to food no deeper than 1 m (3.3 ft) below the tide. Kelp releases a chemical deterrent to protect it from grazing, but canopy kelp releases a lower concentration of the chemical, allowing the sea cow to graze safely.[15][6][23] Steller noted that the sea cow grew thin during the frigid winters, indicating a period of fasting due to low kelp growth.[23] Fossils of Pleistocene Aleutian Island sea cow populations were larger than those from the Commander Islands, indicating that the growth of Commander Island sea cows may have been stunted due to a less favorable habitat and less food than the warmer Aleutian Islands.[12]

1898 illustration of a Steller's sea cow family

Steller described the sea cow as being highly social (

gregarious). It lived in small family groups and helped injured members, and was also apparently monogamous. Steller's sea cow may have exhibited parental care, and the young were kept at the front of the herd for protection against predators. Steller reported that as a female was being captured, a group of other sea cows attacked the hunting boat by ramming and rocking it, and after the hunt, her mate followed the boat to shore, even after the captured animal had died. Mating season occurred in early spring and gestation took a little over a year, with calves likely delivered in autumn, as Steller observed a greater number of calves in autumn than at any other time of the year. Since female sea cows had only one set of mammary glands, they likely had one calf at a time.[5]

The sea cow used its fore limbs for swimming, feeding, walking in shallow water, defending itself, and holding on to its partner during copulation.[5] According to Steller, the fore limbs were also used to anchor the sea cow down to prevent it from being swept away by the strong nearshore waves.[6] While grazing, the sea cow progressed slowly by moving its tail (fluke) from side to side; more rapid movement was achieved by strong vertical beating of the tail. They often slept on their backs after feeding. According to Steller, the sea cow was nearly mute and made only heavy breathing sounds, raspy snorting similar to a horse, and sighs.[5]

Despite their large size, as with many other marine megafauna in the region, Steller's sea cows may have been prey for the local

transient orcas (Orcinus orca); it is likely that they experienced predation, as Steller observed that foraging sea cows with calves would always keep their calves between themselves and the shore, and orcas would have been the most likely candidate for causing this behavior. In addition, early indigenous peoples of the North Pacific may have depended on the sea cow for food, and it is possible that this dependency may have extirpated the sea cow from portions of the North Pacific aside from the Commander Islands. Steller's sea cows may have also had a mutualistic (or possibly even parasitic) relationship with local seabird species; Steller often observed birds perching on the exposed backs of the sea cows, feeding on the parasitic Cyamus rhytinae; this unique relationship that disappeared with the sea cows may have been a food source for many birds, and is similar to the recorded interactions between oxpeckers (Buphagus) and extant African megafauna.[24]

Taxonomy

Phylogeny

A gray dugong swimming in the water: The underside is visible, and it has large limbs behind the head, pointed down. They are triangular in shape, similar to a dolphin fin. It has a thin body compared to the head, and a forked tail fluke like that of a dolphin. It has a small eye.
A gray dugong bottom feeding, with plumes of sand trailing from it mouth. It is resting its hands on the ground. Small sprouts of seagrasses litter on the ground, and yellow fish with black stripes are hovering around its snout. The snout has two large nostrils, and the mouth is on the ground.
The closely related dugong
Relations within Sirenia
Sirenia
Based on a 2015 study by Mark Springer[25]
Relations within Hydrodamalinae
Sirenia
Based on a 2004 study by Hitoshi Furusawa[26]

Steller's sea cow was a member of the

mya.[29] Steller's sea cow is a member of the family Dugongidae, the sole surviving member of which, and thus Steller's sea cow's closest living relative, is the dugong (Dugong dugon).[30]

Steller's sea cow was a direct descendant of the

derived than the Cuesta sea cow. This has led some to believe that the Takikawa sea cow is its own species.[26] The evolution of the genus Hydrodamalis was characterized by increased size, and a loss of teeth and phalanges, as a response to the onset of the Quaternary glaciation.[31][5]

Research history

Steller's sea cow was discovered in 1741 by Georg Wilhelm Steller, and was named after him. Steller researched the wildlife of Bering Island while he was shipwrecked there for about a year;[32] the animals on the island included relict populations of sea cows, sea otters, Steller sea lions, and northern fur seals.[33] As the crew hunted the animals to survive, Steller described them in detail. Steller's account was included in his posthumous publication De bestiis marinis, or The Beasts of the Sea, which was published in 1751 by the Russian Academy of Sciences in Saint Petersburg. Zoologist Eberhard von Zimmermann formally described Steller's sea cow in 1780 as Manati gigas. Biologist Anders Jahan Retzius in 1794 put the sea cow in the new genus Hydrodamalis, with the specific name of stelleri, in honor of Steller.[4] In 1811, naturalist Johann Karl Wilhelm Illiger reclassified Steller's sea cow into the genus Rytina, which many writers at the time adopted. The name Hydrodamalis gigas, the correct combinatio nova if a separate genus is recognised, was first used in 1895 by Theodore Sherman Palmer.[5]

Stejneger
's 1925 reconstruction of G. W. Steller measuring a sea cow in 1742

For decades after its discovery, no skeletal remains of a Steller's sea cow were known.

Leonhard Hess Stejneger unearthed many skeletal remains from different individuals in the late 1800s, from which composite skeletons were assembled. As of 2006, 27 nearly complete skeletons and 62 complete skulls have been found, but most of them are assemblages of bones from two to 16 different individuals.[13]

In 2021, the

nuclear genome was sequenced.[19]

Illustrations

The Pallas Picture is the only known drawing of Steller's sea cow believed to be from a complete specimen. It was published by Peter Simon Pallas in his 1840 work Icones ad Zoographia Rosso-Asiatica. Pallas did not specify a source; Stejneger suggested it may have been one of the original illustrations produced by Friedrich Plenisner, a member of Vitus Bering's crew as a painter and surveyor who drew a figure of a female sea cow on Steller's request. Most of Plenisner's depictions were lost during transit from Siberia to Saint Petersburg.[35][36]

Another drawing of Steller's sea cow similar to the Pallas Picture appeared on a 1744 map drawn by Sven Waxell and Sofron Chitrow. The picture may have also been based upon a specimen, and was published in 1893 by Pekarski. The map depicted Vitus Bering's route during the Great Northern Expedition, and featured illustrations of Steller's sea cow and Steller's sea lion in the upper-left corner. The drawing contains some inaccurate features such as the inclusion of eyelids and fingers, leading to doubt that it was drawn from a specimen.[35][36]

Johann Friedrich von Brandt, director of the Russian Academy of Sciences, had the "Ideal Image" drawn in 1846 based upon the Pallas Picture, and then the "Ideal Picture" in 1868 based upon collected skeletons. Two other possible drawings of Steller's sea cow were found in 1891 in Waxell's manuscript diary. There was a map depicting a sea cow, as well as a Steller sea lion and a northern fur seal. The sea cow was depicted with large eyes, a large head, claw-like hands, exaggerated folds on the body, and a tail fluke in perspective lying horizontally rather than vertically. The drawing may have been a distorted depiction of a juvenile, as the figure bears a resemblance to a manatee calf. Another similar image was found by Alexander von Middendorff in 1867 in the library of the Russian Academy of Sciences, and is probably a copy of the Tsarskoye Selo Picture.[35][36]

Early depictions of Steller's sea cow[35][36]

Range

Steller's sea cow distribution; yellow during the Pleistocene; red for archaeological evidence; and blue for historical records

The range of Steller's sea cow at the time of its discovery was apparently restricted to the shallow seas around the

Aleuts from Attu Island and Atka Island there.[38]

The first

Middle Pleistocene rib bone from the Bōsō Peninsula of Japan.[41] The remains of three individuals were found preserved in the South Bight Formation of Amchitka; as late Pleistocene interglacial deposits are rare in the Aleutians, the discovery suggests that sea cows were abundant in that era. According to Steller, the sea cow often resided in the shallow, sandy shorelines and in the mouths of freshwater rivers.[12] Genetic evidence suggests Steller's sea cow, as well as the modern dugong, suffered a population bottleneck (a significant reduction in population) bottoming roughly 400,000 years ago.[19]

Bone fragments and accounts by native Aleut people suggest that sea cows also historically inhabited the

CE.[37]

Interactions with humans

Extinction

Genetic evidence suggests the Steller's sea cows around the Commander Islands were the last of a much more ubiquitous population dispersed across the North Pacific coastal zones. They had the same

inbred population of woolly mammoths on Wrangel Island. During glacial periods and reduction in sea levels and temperatures, suitable habitat substantially regressed, fragmenting the population. By the time sea levels stabilized around 5,000 years ago, the population had already plummeted. Together, these indicate that even without human influence, the Steller's sea cow would have still been a dead clade walking, with the vast majority of the population having already gone extinct from natural climatic and sea level shifts, with the tiny remaining population at major risk from a genetic extinction vortex.[19]

A sea otter swimming on its back, holding a sea urchin and smashing a rock against it
The sea otter is a keystone species and keeps sea urchin populations in check. Its depopulation in the Aleutian Islands may have led to the decline of kelp and subsequently of sea cows.[23]

The presence of Steller's sea cows in the Aleutian Islands may have caused the Aleut people to migrate westward to hunt them. This possibly led to the sea cow's extirpation in that area, assuming it had not already happened yet, but the archaeological evidence is inconclusive.

Siberian Yupik people who have inhabited St. Lawrence island for 2,000 years. They may have hunted the sea cows into extinction, as the natives have a dietary culture heavily dependent upon marine mammals. The onset of the Medieval Warm Period, which reduced the availability of kelp, may have also been the cause for their local extinction in that area.[37] It has also been argued that the decline of Steller's sea cow may have been an indirect effect of the harvesting of sea otters by the area's aboriginal people. With the otter population reduced, the sea urchin population would have increased, in turn reducing the stock of kelp, its principal food.[23][39] In historic times, though, aboriginal hunting had depleted sea otter populations only in localized areas,[39] and as the sea cow would have been easy prey for aboriginal hunters, accessible populations may have been exterminated with or without simultaneous otter hunting. In any event, the range of the sea cow was limited to coastal areas off uninhabited islands by the time Bering arrived, and the animal was already endangered.[45][11]

When Europeans discovered them, there may have been only 2,000 individuals left.[19] This small population was quickly wiped out by fur traders, seal hunters, and others who followed Vitus Bering's route past its habitat to Alaska.[46] It was also hunted to collect its valuable subcutaneous fat. The animal was hunted and used by Ivan Krassilnikov in 1754 and Ivan Korovin 1762, but Dimitri Bragin, in 1772, and others later, did not see it. Brandt thus concluded that by 1768, twenty-seven years after it had been discovered by Europeans, the species was extinct.[1][39][47] In 1887, Stejneger estimated that there had been fewer than 1,500 individuals remaining at the time of Steller's discovery, and argued there was already an immediate danger of the sea cow's extinction.[1]

The first attempt to hunt the animal by Steller and the other crew members was unsuccessful due to its strength and thick hide. They had attempted to impale it and haul it to shore using a large hook and heavy cable, but the crew could not pierce its skin. In a second attempt a month later, a harpooner speared an animal, and men on shore hauled it in while others repeatedly stabbed it with bayonets. It was dragged into shallow waters, and the crew waited until the tide receded and it was beached to butcher it.[33] After this, they were hunted with relative ease, the challenge being in hauling the animal back to shore. This bounty inspired maritime fur traders to detour to the Commander Islands and restock their food supplies during North Pacific expeditions.[12]

Impact of extinction

While not a keystone species, Steller's sea cows likely influenced the community composition of the kelp forests they inhabited, and also boosted their productivity and resilience to environmental stressors by allowing more light into kelp forests and more kelp to grow, and enhancing the recruitment and dispersal of kelp through their feeding behavior. In the modern day, the flow of nutrients from kelp forests to adjacent ecosystems is regulated by the seasons, with seasonal storms and currents being the primary factor. The Steller's sea cow may have allowed this flow to continue year-round, thus allowing for more productivity in adjacent habitats. The disturbance caused by the Steller's sea cow may have facilitated the dispersal of kelp, most notably Nereocystis species, to other habitats, allowing recruitment and colonization of new areas, and facilitating genetic exchange. Their presence may have also allowed sea otters and large marine invertebrates to coexist, indicating a commonly-documented decline in marine invertebrate populations driven by sea otters (an example being in populations of the black leather chiton)[48] may be due to lost ecosystem functions associated with the Steller's sea cow. This indicates that due to the sea cow's extinction, the ecosystem dynamics and resilience of North Pacific kelp forests may have already been compromised well before more well-known modern stressors like overharvesting and climate change.[49][24]

Later reported sightings

Sea cow sightings have been reported after Brandt's official 1768 date of extinction.

ethnologist and naturalist, said the natives of Attu Island reported that the sea cows survived into the 1800s, and were sometimes hunted.[43]

In 1963, the official journal of the

Kamchatka,[50] in the Gulf of Anadyr. The crew reported seeing six of these animals ranging from 6 to 8 meters (20 to 26 ft), with trunks and split lips. There have also been alleged sightings by local fishermen in the northern Kuril Islands, and around the Kamchatka and Chukchi peninsulas.[51][52]

Uses

Zoologisk Museum

Steller's sea cow was described as being "tasty" by Steller; the meat was said to have a taste similar to

baidarkas or umiaks.[15]

Towards the end of the 19th century, bones and fossils from the extinct animal were valuable and often sold to museums at high prices. Most were collected during this time, limiting trade after 1900.

Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), which restrict the trade of marine mammal products. Although the distribution is legal, the sale of unfossilized bones is generally prohibited and trade in products made of the bones is regulated because some of the material is unlikely to be authentic and probably comes from arctic cetaceans.[13][54]

The

ethnographer Elizabeth Porfirevna Orlova, from the Russian Museum of Ethnography, was working on the Commander Island Aleuts from August to September 1961. Her research includes notes about a game of accuracy, called kakan ("stones") played with the bones of the Steller's sea cow. Kakan was usually played at home between adults during bad weather, at least during Orlova's fieldwork.[55]

In media and folklore

On slightly yellow paper using black ink, there is Kotick the white seal with his arms protruding straight up out of the water. He is facing a sea cow who is darkly shaded, has large nostrils, small eyes, stocky body, and covered in seaweed. Behind Kotick is another sea cow who is eating seaweed, and in the background there are many other sea cows. One of the sea cows is sticking its tail out of the water, which resembles that of a dolphin. The coastline is visible to the right.
Kotick the white seal talking to sea cows in Rudyard Kipling's The Jungle Book (1895)

In the story The White Seal from The Jungle Book by Rudyard Kipling, which takes place in the Bering Sea, Kotick the rare white seal consults Sea Cow during his journey to find a new home.[56][57]

Tales of a Sea Cow is a 2012

Etienne de France about a fictional 2006 discovery of Steller's sea cows off the coast of Greenland.[58] The film has been exhibited in art museums and universities in Europe.[59][60]

Steller's sea cows appear in two books of poetry:

Winfried Georg Sebald, and Species Evanescens (2009) by Russian poet Andrei Bronnikov. Bronnikov's book depicts the events of the Great Northern Expedition through the eyes of Steller;[61] Sebald's book looks at the conflict between man and nature, including the extinction of Steller's sea cow.[62]

The novel Elolliset (Living things) (2023) by Finnish author and literary scholar Iida Turpeinen uses Steller's sea cow and its demise as a central theme. It features multiple characters at different times in history that were involved with the animal, beginning from Steller’s expedition and telling how the complete skeleton was conserved and ended up in the Helsinki museum of natural history.[63]

See also

References

  1. ^
    doi:10.2305/IUCN.UK.2016-2.RLTS.T10303A43792683.en
    . Retrieved 17 February 2022.
  2. OCLC 62265494
    .
  3. OCLC 62265494
    .
  4. ^
    S2CID 36945810
    .
  5. ^
    JSTOR 3503855. Archived from the original
    (PDF) on 2016-10-20.
  6. ^
    OCLC 778803577
    .
  7. ^ "Found: The Massive Skeleton of a Steller's Sea Cow". 17 November 2017. Retrieved 6 December 2017.
  8. ^ "Steller's sea cow – Sunken flagship of the Bering Sea... – The AMIQ Institute". Retrieved 6 December 2017.
  9. ^ "Skeleton of Ancient Sea Cow Found on Bering Island". The Commander Islands Nature and Biosphere Reserve Named Marakov S.V. Retrieved 3 December 2017.
  10. JSTOR 1379236
    .
  11. ^
    PMID 17148336
    .
  12. ^
    doi:10.3133/pp1036
    .
  13. ^
    doi:10.1578/AM.32.3.2006.273
    .
  14. OCLC 757476446
    . Steller described the sea cow's blubber, 8–10 centimeters (3.1–3.9 in) thick, as...
  15. ^
    OCLC 262718627
    .
  16. ^ Haeckel (1895). Systematische Phylogenie der Wirbelthiere (Vertebrata). Entwurf einer systematischen Stammesgeschichte (in German). Vol. 3 (1 ed.). Berlin: Georg Reimer. pp. 142–143. Retrieved 16 July 2021.
  17. OCLC 953575838
    . The skeleton of sirenians displays both pachyostosis and osteosclerosis...
  18. ^ Takahashi, S.; Domning, D. P.; Saito, T. (1986). "Dusisiren dewana, n. sp. (Mammalia: Sirenia), a new ancestor of Steller's sea cow from the upper Miocene of Yamagata Prefecture, northeastern Japan" (PDF). Transactions and Proceedings of the Paleontological Society of Japan. New Series (141): 296–321. ...the phalanges were even more reduced, and possibly even completely lost, in Steller's sea cow.
  19. ^
    PMID 33850161
    .
  20. OCLC 929783662
    .
  21. ^ "WoRMS - World Register of Marine Species - Cyamus rhytinae (J.F. Brandt, 1846)". www.marinespecies.org. Retrieved 2021-08-19.
  22. JSTOR 221694
    . Syrenocyamus rhytinae was recorded from the Steller's Sea Cow...cyamid amphipods are known only from whales and dolphins, and have never (since Steller) been recorded in sirenians.
  23. ^
    PMID 26504217
    .
  24. ^
    S2CID 238770019
    .
  25. PMID 26050523
    .
  26. ^
    S2CID 83992432
    .
  27. OCLC 895212825
    .
  28. ^ "Hydrodamalinae". Fossilworks. Gateway to the Paleobiology Database. Retrieved 12 March 2017.
  29. S2CID 28213762
    .
  30. OCLC 27492815. Archived from the original
    (PDF) on 2013-05-11.
  31. ^
    JSTOR 2412510
    .
  32. OCLC 877954975
    .
  33. ^
    OCLC 851981991
    .
  34. ^ "Look, no hands: Steller's sea cow". The Guardian – Science Animal magic. 25 March 2016. Retrieved 3 December 2017.
  35. ^
    OCLC 836920902
    .
  36. ^ a b c d Buechner, E. (1891). "Nordischen Seekuh". Memoirs of the Imperial Academy of St. Petersburg Science (in German). 38 (7): 1–24.
  37. ^
    PMID 25428930
    .
  38. PMID 12082644
    . In 1825–1826, the Russian-American company transferred Aleut families from Attu Island, the westernmost of the Aleutian chain, as well as from Atka/Andreyanov Islands, to the Commanders
  39. ^
    doi:10.1111/j.1748-7692.1995.tb00294.x
    .
  40. OCLC 488523994
    .
  41. doi:10.14825/kaseki.56.0_26
    .
  42. S2CID 226791158
    .
  43. ^
    doi:10.1111/j.1748-7692.2007.00153.x
    .
  44. ^
    doi:10.1016/j.palaeo.2004.02.009
    .
  45. OCLC 961898476
    .
  46. OCLC 49225731
    . Each year, one or more vessels left Okhotsk or Petropavlosk on Kamchatka for hunting trips to the [Aleutian] islands. Typically, the ships would sail to the Commander Islands, where they would spend some time slaughtering and preserving the mat of Steller's rhytina (a sea cow)...
  47. JSTOR 23049853
    .
  48. PMID 17913138
    .
  49. doi:10.14288/1.0391881
    . Retrieved 2021-08-19.
  50. OCLC 473809649
    .
  51. ^ Berzin, A. A.; Tikhomirov, E. A.; Troinin, V. I. (2007) [1963]. "Ischezla li Stellerova korova?" [Was Steller's sea cow exterminated?] (PDF). Priroda. 52 (8). Translated by Ricker, W. E.: 73–75.
  52. ^ Bertram, C.; Bertram, K. (1964). "Does the 'extinct' sea cow survive?". New Scientist. 24 (415): 313.
  53. ^ Littlepage, Dean. Steller's Island: Adventures of a Pioneer Naturalist in Alaska.
  54. S2CID 35462508
    .
  55. ^ Korsun, S. A. (2013). "Fieldwork on the Commander Islands Aleuts" (PDF). Alaska Journal of Anthropology. 11 (1–2): 169–181.
  56. OCLC 883570362
    .
  57. OCLC 851153394
    .
  58. ^ "Tales of a Sea Cow (2012)". IMDb. Retrieved 20 January 2017.
  59. ^ "Etienne de France, 'Tales of a Sea Cow' — Exhibition at Parco Arte Vivente, Torino, Italy". alan-shapiro.com. Archived from the original on 2014-05-02. Retrieved 2014-05-01.
  60. ^ Bureaud, Annick. "Tales of a Sea Cow: A Fabulatory Science Story" (PDF). Retrieved August 19, 2016.
  61. OCLC 676724013
    .
  62. ^ Sebald, W. G. "Nach der Natur Sebald" (in German). Hanser Literaturverlage. Retrieved 19 January 2017.
  63. ^ Turpeinen, Iida. "Elolliset" (in Finnish). Schildts&Söderströms. Retrieved 6 January 2023.

Further reading

External links

Wikimedia Commons has media related to Hydrodamalis gigas.
Wikispecies has information related to Hydrodamalis gigas.
Retrieved from "https://en.wikipedia.org/w/index.php?title=Steller%27s_sea_cow&oldid=1220569154"