153-407: The dugong ( / ˈ d ( j ) uː ɡ ɒ ŋ / ; Dugong dugon ) is a marine mammal . It is one of four living species of the order Sirenia , which also includes three species of manatees . It is the only living representative of the once-diverse family Dugongidae ; its closest modern relative, Steller's sea cow ( Hydrodamalis gigas ), was hunted to extinction in the 18th century. The dugong
306-581: A Philippine subspecies. Others postulate that the populations formed part of a super-population where migration between Ryukyu , Taiwan , and the Philippines was common. It has been confirmed that dugongs once inhabited the water of the Mediterranean possibly until after the rise of civilizations along the inland sea . This population possibly shared ancestry with the Red Sea population, and
459-581: A monophyletic group with hyraxes and the aardvark , one of the earliest offshoots of eutherians . The fossil record shows sirenians appearing in the Eocene , where they most likely lived in the Tethys Ocean . The two extant families of sirenians are thought to have diverged in the mid-Eocene, after which the dugongs and their closest relative, the Steller's sea cow , split off from a common ancestor in
612-605: A utaki that outsiders are strictly forbidden to enter. Dugong populations in these areas were reduced by historical hunts as payments to the Ryukyu Kingdom , before being wiped out because of large-scale illegal hunting and fishing using destructive methods such as dynamite fishing after the Second World War. Populations around Taiwan appear to be almost extinct, although remnant individuals may visit areas with rich seagrass beds such as Dongsha Atoll . Some of
765-405: A blunt snout and reduced dentition rely on suction feeding . Though carnivorous, they house gut flora similar to that of terrestrial herbivores, probably a remnant of their herbivorous ancestry. Baleen whales use their baleen plates to sieve plankton, among others, out of the water; there are two types of methods: lunge-feeding and gulp-feeding. Lunge-feeders expand the volume of their jaw to
918-413: A certain range their entire lives. Large numbers often move together from one area to another. It is thought that these movements are caused by changes in seagrass availability. Their memory allows them to return to specific points after long travels. Dugong movements mostly occur within a localized area of seagrass beds, and animals in the same region show individualistic patterns of movement. Daily movement
1071-446: A depth of around 10 m (33 ft), although in areas where the continental shelf remains shallow dugongs have been known to travel more than ten kilometres (6 mi) from the shore, descending to as far as 37 metres (121 ft), where deepwater seagrasses such as Halophila spinulosa are found. Special habitats are used for different activities. It has been observed that shallow waters are used as sites for calving, minimizing
1224-672: A descendant of the Proto-Austronesian language , began to break up by at least 2000 BCE, possibly as a result of the southward expansion of Austronesian peoples into Maritime Southeast Asia from the island of Taiwan . The history of the Malay language can be divided into five periods: Old Malay, the Transitional Period, the Classical Malay, Late Modern Malay and Modern Malay. Old Malay is believed to be
1377-627: A divergence of the Monachinae (monk seals) and Phocinae lineages 22 mya. Fossil evidence indicates the sea otter ( Enhydra ) lineage became isolated in the North Pacific approximately two mya, giving rise to the now-extinct † Enhydra macrodonta and the modern sea otter, Enhydra lutris . The sea otter evolved initially in northern Hokkaidō and Russia, and then spread east to the Aleutian Islands , mainland Alaska , and down
1530-526: A dugong can change due to the growth of algae on the skin. The body is sparsely covered in short hair, a common feature among sirenians which may allow for tactile interpretation of their environment. These hairs are most developed around the mouth, which has a large horseshoe-shaped upper lip forming a highly mobile muzzle. This muscular upper lip aids the dugong in foraging . The dugong's tail flukes and flippers are similar to those of dolphins . These flukes are raised up and down in long strokes to move
1683-471: A few are specialists. They typically hunt non-schooling fish, slow-moving or immobile invertebrates or endothermic prey when in groups. Solitary foraging species usually exploit coastal waters, bays and rivers. When large schools of fish or squid are available, pinnipeds hunt cooperatively in large groups, locating and herding their prey. Some species, such as California and South American sea lions, may forage with cetaceans and sea birds. The polar bear
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#17327653334341836-501: A few eat other mammals. While the number of marine mammals is small compared to those found on land, their roles in various ecosystems are large, especially concerning the maintenance of marine ecosystems, through processes including the regulation of prey populations. This role in maintaining ecosystems makes them of particular concern as 23% of marine mammal species are currently threatened. Marine mammals were first hunted by aboriginal peoples for food and other resources. Many were also
1989-402: A few times during their lives and invest considerable parental care in their young. The time between births is unclear, with estimates ranging from 2.4 to 7 years. Mating behaviour varies between populations located in different areas. In some populations, males will establish a territory that females in estrus will visit. In these areas, a male will try to impress the females while defending
2142-527: A lingua franca derived from Classical Malay as well as Makassar Malay , which appears to be a mixed language . Malay historical linguists agree on the likelihood of the Malayic homeland being in western Borneo . A form known as Proto-Malayic was spoken in Borneo at least by 1000 BCE, it has been argued to be the ancestral language of all subsequent Malayic languages . Its ancestor, Proto-Malayo-Polynesian ,
2295-719: A maximum depth of 39 metres (128 ft); they spend most of their lives no deeper than 10 metres (33 ft). Communication between individuals is through chirps, whistles, barks, and other sounds that echo underwater. Different sounds have been observed with different amplitudes and frequencies, implying different purposes. Visual communication is limited due to poor eyesight and is mainly used for activities such as lekking for courtship purposes. Mothers and calves are in almost constant physical contact, and calves have been known to reach out and touch their mothers with their flippers for reassurance. Dugongs are semi-nomadic , often traveling long distances in search of food, but staying within
2448-555: A mid vowel [e, o] . Orthographic note : both /e/ and /ə/ are written with ⟨e⟩ . Orthographic /e, o/ are relatively rare, so the letter ⟨e⟩ usually represents /ə/ . There are some homographs; for example, perang is used for both /pəraŋ/ "war" and /peraŋ ~ piraŋ/ "blond". (In Indonesia, "blond" may be written perang or pirang .) Some analyses regard /ai, au, oi/ as diphthongs. However, [ai] and [au] can only occur in open syllables, such as cukai ("tax") and pulau ("island"). Words with
2601-698: A number of features for efficient locomotion such as torpedo-shaped bodies to reduce drag; modified limbs for propulsion and steering ; tail flukes and dorsal fins for propulsion and balance. Marine mammals are adept at thermoregulation using dense fur or blubber , circulatory adjustments ( counter-current heat exchange ); and reduced appendages, and large size to prevent heat loss. Marine mammals are able to dive for long periods. Both pinnipeds and cetaceans have large and complex blood vessel systems pushing large volumes of blood rich in myoglobin and hemoglobin , which serve to store greater quantities of oxygen . Other important reservoirs include muscles and
2754-438: A number of terrestrial habitats, both continental and island. In temperate and tropical areas, they haul-out on to sandy and pebble beaches, rocky shores , shoals , mud flats , tide pools and in sea caves . Some species also rest on man-made structures, like piers , jetties , buoys and oil platforms . Seals may move further inland and rest in sand dunes or vegetation, and may even climb cliffs. Most cetaceans live in
2907-629: A period of glaciation in the Pleistocene or from the eastern part of Siberia , (from Kamchatka and the Kolym Peninsula). The oldest known polar bear fossil is a 130,000-to-110,000-year-old jaw bone, found on Prince Charles Foreland in 2004. The mitochondrial DNA (mtDNA) of the polar bear diverged from the brown bear roughly 150,000 years ago. Further, some clades of brown bear, as assessed by their mtDNA, are more closely related to polar bears than to other brown bears, meaning that
3060-434: A phonetic diphthong in a closed syllable, such as baik ("good") and laut ("sea"), are actually two syllables. An alternative analysis therefore treats the phonetic diphthongs [ai] , [au] and [oi] as a sequence of a monophthong plus an approximant: /aj/ , /aw/ and /oj/ respectively. There is a rule of vowel harmony : the non-open vowels /i, e, u, o/ in bisyllabic words must agree in height, so hidung ("nose")
3213-431: A root word ( affixation ), formation of a compound word (composition), or repetition of words or portions of words ( reduplication ). Nouns and verbs may be basic roots, but frequently they are derived from other words by means of prefixes , suffixes and circumfixes . Malay does not make use of grammatical gender , and there are only a few words that use natural gender; the same word is used for 'he' and 'she' which
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#17327653334343366-442: A seal to appear. When the seal exhales, the bear smells its breath, reaches into the hole with a forepaw, and drags it out onto the ice. The polar bear also hunts by stalking seals resting on the ice. Upon spotting a seal, it walks to within 100 yards (90 m), and then crouches. If the seal does not notice, the bear creeps to within 30 to 40 feet (9 to 10 m) of the seal and then suddenly rushes to attack. A third hunting method
3519-431: A unique skull and teeth. Its snout is sharply downturned, an adaptation for feeding in benthic seagrass communities. The molar teeth are simple and peg-like, unlike the more elaborate molar dentition of manatees. The dugong has been hunted for thousands of years for its meat and oil . Traditional hunting still has great cultural significance in several countries in its modern range, particularly northern Australia and
3672-430: A volume bigger than the original volume of the whale itself by inflating their mouth. This causes grooves on their throat to expand, increasing the amount of water the mouth can store. They ram a baitball at high speeds in order to feed, but this is only energy-effective when used against a large baitball. Gulp-feeders swim with an open mouth, filling it with water and prey. Prey must occur in sufficient numbers to trigger
3825-426: Is 2.0.3.3 3.1.3.3 , meaning they have two incisors, three premolars , and three molars on each side of their upper jaw, and three incisors, one canine, three premolars, and three molars on each side of their lower jaw. Like other sirenians, the dugong experiences pachyostosis , a condition in which the ribs and other long bones are unusually solid and contain little or no marrow . These heavy bones, which are among
3978-402: Is dia or for 'his' and 'her' which is dia punya . There is no grammatical plural in Malay either; thus orang may mean either 'person' or 'people'. Verbs are not inflected for person or number, and they are not marked for tense; tense is instead denoted by time adverbs (such as 'yesterday') or by other tense indicators, such as sudah 'already' and belum 'not yet'. On the other hand, there
4131-456: Is a complex system of verb affixes to render nuances of meaning and to denote voice or intentional and accidental moods . Malay does not have a grammatical subject in the sense that English does. In intransitive clauses, the noun comes before the verb. When there is both an agent and an object , these are separated by the verb (OVA or AVO), with the difference encoded in the voice of the verb. OVA, commonly but inaccurately called "passive",
4284-521: Is a potential danger for local dugongs. On Phu Quoc, the first 'Dugong Festival' was held in 2014, aiming to raise awareness of these issues. In Thailand, the present distribution of dugongs is restricted to six provinces along the Andaman Sea , and very few dugongs are present in the Gulf of Thailand . The Gulf of Thailand was historically home to a large number of animals, but none have been sighted in
4437-453: Is affected by the tides. In areas where there is a large tidal range, dugongs travel with the tide to access shallower feeding areas. In Moreton Bay, dugongs often travel between foraging grounds inside the bay and warmer oceanic waters. At higher latitudes dugongs make seasonal travels to reach warmer water during the winter. Occasionally individual dugongs make long-distance travels over many days and can travel over deep ocean waters. One animal
4590-430: Is allowed but * hedung is not. Pronunciation Pronunciation Pronunciation Study by Uri Tadmor which was published in 2003 shows that mutation of ⟨a⟩ in final open syllable is an areal feature. Specifically, it is an areal feature of Western Austronesia. Uri Tadmor classify those types into four groups as below. Malay is an agglutinative language , and new words are formed by three methods: attaching affixes onto
4743-568: Is an Austronesian language that is an official language of Brunei , Indonesia , Malaysia , and Singapore . It is also spoken in East Timor and parts of Thailand . Altogether, it is spoken by 290 million people (around 260 million in Indonesia alone in its own literary standard named " Indonesian ") across Maritime Southeast Asia . The language is pluricentric and a macrolanguage , i.e., several varieties of it are standardized as
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4896-406: Is designated the bahasa persatuan/pemersatu ("unifying language" or lingua franca ) whereas the term "Malay" ( bahasa Melayu ) is domestically restricted to vernacular varieties of Malay indigenous to areas of Central to Southern Sumatra and West Kalimantan . Classical Malay , also called Court Malay, was the literary standard of the pre-colonial Malacca and Johor Sultanates and so
5049-482: Is divided into Bornean and Sumatran Malay; some of the most widely spoken Sumatran Malay dialects are Riau Malay , Langkat , Palembang Malay and Jambi Malay . Minangkabau , Kerinci and Bengkulu are believed to be Sumatran Malay descendants. Meanwhile, the Jakarta dialect (known as Betawi ) also belongs to the western Malay group. The eastern varieties, classified either as dialects or creoles , are spoken in
5202-530: Is herding, where a pod squeezes a school of fish into a small volume, known as a bait ball . Individual members then take turns plowing through the ball, feeding on the stunned fish. Coralling is a method where dolphins chase fish into shallow water to catch them more easily. Killer whales and bottlenose dolphins have also been known to drive their prey onto a beach to feed on it. Killer whales have been known to paralyze great white sharks and other sharks and rays by flipping them upside down. Other whales with
5355-574: Is illegal and there is widespread disapproval of killing dugongs, poaching remains a major problem. Dugongs are also widely hunted in Papua New Guinea , the Solomon Islands , Vanuatu , and New Caledonia ; where their meat and ornaments made from bones and tusks are highly prized in feasts and traditional rituals. However, hunting dugongs is considered taboo in some areas of Vanuatu. Dugong meat and oil have traditionally been some of
5508-623: Is not a tonal language . The consonants of Malaysian and also Indonesian are shown below. Non-native consonants that only occur in borrowed words, principally from Arabic, Dutch and English, are shown in brackets. Orthographic note : The sounds are represented orthographically by their symbols as above, except: Loans from Arabic : Malay originally had four vowels, but in many dialects today, including Standard Malay, it has six, with /i/ split into /i, e/ and /u/ split into /u, o/ . Many words are commonly pronounced variably, with either [i, u] or [e, o] , and relatively few words require
5661-569: Is not readily intelligible with the standard language , and the same is true with some lects on the Malay Peninsula such as Kedah Malay . However, both Brunei and Kedah are quite close. Malay is now written using the Latin script , known as Rumi in Brunei, Malaysia and Singapore or Latin in Indonesia, although an Arabic script called Arab Melayu or Jawi also exists. Latin script
5814-541: Is now believed to be small and scattered. A small population existed along the southern coast of China , particularly the Gulf of Tonkin (Beibu Gulf), where efforts were made to protect it, including the establishment of a seagrass sanctuary for dugong and other endangered marine fauna ranging in Guangxi . Despite these efforts, numbers continued to decrease, and in 2007 it was reported that no more dugong could be found on
5967-651: Is official in Malaysia, Singapore, and Indonesia. Malay uses Hindu-Arabic numerals . Rumi (Latin) and Jawi are co-official in Brunei only. Names of institutions and organisations have to use Jawi and Rumi (Latin) scripts. Jawi is used fully in schools, especially the religious school, sekolah agama , which is compulsory during the afternoon for Muslim students aged from around 6–7 up to 12–14. Efforts are currently being undertaken to preserve Jawi in Malaysia, and students taking Malay language examinations in Malaysia have
6120-642: Is possibly the last long-term viable population in East Africa, with only some of its core territory lying within protected waters. The East African population is genetically distinct from those of the Red Sea and those off Madagascar. In Tanzania , observations have recently increased around the Mafia Island Marine Park where a hunt was intended by fishermen but failed in 2009. In the Seychelles , dugongs had been regarded as extinct in
6273-418: Is scarce. West Indian manatees eat up to 60 different species of plants, as well as fish and small invertebrates to a lesser extent. Sea otters are a classic example of a keystone species; their presence affects the ecosystem more profoundly than their size and numbers would suggest. They keep the population of certain benthic (sea floor) herbivores, particularly sea urchins , in check. Sea urchins graze on
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6426-521: Is similar to Kelantanese Malay, but the language has no official status or recognition. Owing to earlier contact with the Philippines , Malay words—such as dalam hati (sympathy), luwalhati (glory), tengah hari (midday), sedap (delicious)—have evolved and been integrated into Tagalog and other Philippine languages . By contrast, Indonesian has successfully become the lingua franca for its disparate islands and ethnic groups, in part because
6579-624: Is the basic and most common word order. The Malay language has many words borrowed from Arabic (in particular religious terms), Sanskrit , Tamil , certain Sinitic languages , Persian (due to historical status of Malay Archipelago as a trading hub), and more recently, Portuguese , Dutch and English (in particular many scientific and technological terms). There is a group of closely related languages spoken by Malays and related peoples across Brunei , Indonesia , Malaysia , Singapore , Southern Thailand , Kampung Alor in East Timor , and
6732-408: Is the development of echolocation in whales and dolphins. Toothed whales emit a focused beam of high-frequency clicks in the direction that their head is pointing. Sounds are generated by passing air from the bony nares through the phonic lips. These sounds are reflected by the dense concave bone of the cranium and an air sac at its base. The focused beam is modulated by a large fatty organ known as
6885-525: Is the lack of possessive pronouns (and suffixes) in eastern dialects. Manado uses the verb pe and Ambon pu (from Malay punya 'to have') to mark possession. So 'my name' and 'our house" are translated in western Malay as namaku and rumah kita but kita pe nama and torang pe rumah in Manado and beta pu nama , katong pu rumah in Ambon dialect. The pronunciation may vary in western dialects, especially
7038-428: Is the most carnivorous species of bear, and its diet primarily consists of ringed ( Pusa hispida ) and bearded ( Erignathus barbatus ) seals. Polar bears hunt primarily at the interface between ice, water, and air; they only rarely catch seals on land or in open water. The polar bear's most common hunting method is still-hunting: The bear locates a seal breathing hole using its sense of smell, and crouches nearby for
7191-720: Is the only marine mammal that catches fish with its forepaws rather than with its teeth. Under each foreleg, sea otters have a loose pouch of skin that extends across the chest which they use to store collected food to bring to the surface. This pouch also holds a rock that is used to break open shellfish and clams, an example of tool use . The sea otters eat while floating on their backs, using their forepaws to tear food apart and bring to their mouths. Marine otters mainly feed on crustaceans and fish. Pinnipeds mostly feed on fish and cephalopods , followed by crustaceans and bivalves , and then zooplankton and warm-blooded prey (like sea birds ). Most species are generalist feeders, but
7344-483: Is the only sirenian in its range, which spans the waters of some 40 countries and territories throughout the Indo-West Pacific . The dugong is largely dependent on seagrass communities for subsistence and is thus restricted to the coastal habitats that support seagrass meadows , with the largest dugong concentrations typically occurring in wide, shallow, protected areas such as bays , mangrove channels ,
7497-437: Is to raid the birth lairs that female seals create in the snow. They may also feed on fish. Sirenians are referred to as "sea cows" because their diet consists mainly of seagrass. When eating, they ingest the whole plant, including the roots, although when this is impossible they feed on just the leaves. A wide variety of seagrass has been found in dugong stomach contents, and evidence exists they will eat algae when seagrass
7650-624: The Cham alphabet are used by the Chams of Vietnam and Cambodia . Old Malay was written using Pallava and Kawi script, as evident from several inscription stones in the Malay region. Starting from the era of kingdom of Pasai and throughout the golden age of the Malacca Sultanate, Jawi gradually replaced these scripts as the most commonly used script in the Malay region. Starting from the 17th century, under Dutch and British influence, Jawi
7803-520: The Eocene . Their evolutionary link to terrestrial mammals was unknown until the 2007 discovery of † Puijila darwini in early Miocene deposits in Nunavut , Canada. Like a modern otter, † Puijila had a long tail, short limbs and webbed feet instead of flippers. The lineages of Otariidae (eared seals) and Odobenidae (walrus) split almost 28 mya. Phocids (earless seals) are known to have existed for at least 15 mya, and molecular evidence supports
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#17327653334347956-486: The Indian Ocean . The variation observed in range size is a result of the different ecological requirements of each species and their ability to cope with a broad range of environmental conditions. The high degree of overlap between marine mammal species richness and areas of human impact on the environment is of concern. Most marine mammals, such as seals and sea otters, inhabit the coast. Seals, however, also use
8109-665: The Lesser Sunda Islands (Indonesia). Dugongs are predominantly not traditionally hunted for food in these regions and they remained plentiful until around the 1970s. Conversely, dugong "tears" are considered aphrodisiacs in other parts of Indonesia , Singapore , Malaysia , Brunei , Thailand , Vietnam , and Cambodia . Dugong meat is considered a luxury food and is also believed to have aphrodisiac properties. They are actively hunted in these regions, in some places to near-extinction. In Palau , dugongs were traditionally hunted with heavy spears from canoes. Although it
8262-727: The Marine National Park, Gulf of Kutch , the only remaining population in western India. It is 1,500 kilometres (800 nautical miles) from the population in the Persian Gulf, and 1,700 kilometres (900 nmi) from the nearest population in India. Former populations in this area, centered on the Maldives and the Lakshadweep , are presumed to be extinct. A population exists in the Gulf of Mannar Marine National Park and
8415-773: The Miocene . The Steller's sea cow became extinct in the 18th century. No fossils exist of other members of the Dugongidae. Molecular studies have been made on dugong populations using mitochondrial DNA . The results have suggested that the population of Southeast Asia is distinct from the others. Australia has two distinct maternal lineages, one of which also contains the dugongs from Africa and Arabia. Limited genetic mixing has taken place between those in Southeast Asia and those in Australia, mostly around Timor . One of
8568-551: The North Atlantic right whale , are critically endangered . Other than being hunted, marine mammals can be killed as bycatch from fisheries, where for example they can become entangled in nets and drown or starve. Increased ocean traffic causes collisions between fast ocean vessels and large marine mammals. Habitat degradation also threatens marine mammals and their ability to find and catch food. Noise pollution , for example, may adversely affect echolocating mammals, and
8721-551: The North Ronaldsay sheep ( Ovis aries ) which normally eats seaweed outside the lambing season, the Eurasian otter ( Lutra lutra ) which is usually found in freshwater but can be found along coastal Scotland , and others. Marine mammals form a diverse group of 129 species that rely on the ocean for their existence. They are an informal group unified only by their reliance on marine environments for feeding. Despite
8874-574: The Old World (such as cetaceans ). The first known quadrupedal sirenian was † Pezosiren from the early middle Eocene. The earliest known sea cows, of the families † Prorastomidae and † Protosirenidae , were both confined to the Eocene, and were pig-sized, four-legged, amphibious creatures. The first members of Dugongidae appeared by the middle Eocene. At this point, sea cows were fully aquatic. Pinnipeds split from other caniforms 50 mya during
9027-629: The Oligocene and Miocene but subsequently declined as a result of climatic cooling, oceanographic changes, and human interference. The word "dugong" derives from the Visayan (probably Cebuano ) dugung . The name was first adopted and popularized by the French naturalist Georges-Louis Leclerc, Comte de Buffon , as " dugon " in Histoire Naturelle (1765), after descriptions of
9180-578: The Palk Strait between India and Sri Lanka , but it is seriously depleted. Recoveries of seagrass beds along former ranges of dugongs, such as the Chilika Lake have been confirmed in recent years, raising hopes for re-colorizations of the species. The population around the Andaman and Nicobar Islands is known only from a few records, and although the population was large during British rule, it
9333-414: The anus . The lungs in a dugong are very long, extending almost as far as the kidneys , which are also highly elongated to cope with the saltwater environment. If the dugong is wounded, its blood will clot rapidly. The skull of a dugong is unique. The skull is enlarged with a sharply down-turned premaxilla , which is stronger in males. The spine has between 57 and 60 vertebrae . Unlike in manatees,
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#17327653334349486-516: The equator . Their historic range is believed to correspond to that of seagrasses from the Potamogetonaceae and Hydrocharitaceae families. The full size of the former range is unknown, although it is believed that the current populations represent the historical limits of the range, which is highly fractured. Their distributions during warmer periods of Holocene might have been broader than today. Today populations of dugongs are found in
9639-522: The hippopotamuses . Sirenians, the sea cows, became aquatic around 40 million years ago. The first appearance of sirenians in the fossil record was during the early Eocene, and by the late Eocene, sirenians had significantly diversified. Inhabitants of rivers, estuaries, and nearshore marine waters, they were able to spread rapidly. The most primitive sirenian, † Prorastomus , was found in Jamaica, unlike other marine mammals which originated from
9792-643: The spleen which all have the capacity to hold a high concentration of oxygen. They are also capable of bradycardia (reduced heart rate), and vasoconstriction (shunting most of the oxygen to vital organs such as the brain and heart) to allow extended diving times and cope with oxygen deprivation. If oxygen is depleted ( hypoxia ), marine mammals can access substantial reservoirs of glycogen that support anaerobic glycolysis . Sound travels differently through water, and therefore marine mammals have developed adaptations to ensure effective communication, prey capture, and predator detection. The most notable adaptation
9945-430: The 'melon'. This acts like an acoustic lens because it is composed of lipids of differing densities. Marine mammals have evolved a wide variety of features for feeding, which are mainly seen in their dentition. For example, the cheek teeth of pinnipeds and odontocetes are specifically adapted to capture fish and squid. In contrast, baleen whales have evolved baleen plates to filter feed plankton and small fish from
10098-580: The 18th century until a small number was discovered around the Aldabra Atoll . This population may belong to a different group than that distributed among the inner isles. Dugongs once thrived among the Chagos Archipelago and Sea Cow Island was named after the species, although the species no longer occurs in the region. There are less than 250 individuals scattered throughout Indian waters. A highly isolated breeding population exists in
10251-584: The 1970s when their numbers declined sharply due to accidental drownings in fishing gear and habitat destruction of seagrass meadows. Today, only isolated populations survive, most notably in the waters of the Calamian Islands in Palawan , Isabela in Luzon , Guimaras , and Mindanao . The dugong became the first marine animal protected by Philippine law, with harsh penalties for harming them. Recently,
10404-748: The Kimberley , Western Australia . Dugong dugon is the only extant species of the family Dugongidae , and one of only four extant species of the Sirenia order, the others forming the manatee family. It was first classified by Müller in 1776 as Trichechus dugon , a member of the manatee genus previously defined by Linnaeus . It was later assigned as the type species of Dugong by Lacépède and further classified within its own family by Gray and subfamily by Simpson . Dugongs and other sirenians are not closely related to other marine mammals , being more related to elephants . Dugongs and elephants share
10557-404: The Malay world of Southeast Asia, and was one of the oldest testimonies to the advent of Islam as a state religion in the region. It contains the proclamation issued by a ruler of Terengganu known as Seri Paduka Tuan, urging his subjects to extend and uphold Islam and providing 10 basic Sharia laws for their guidance. The classical Malay language came into widespread use as the lingua franca of
10710-1057: The Malayic languages spoken by the Orang Asli ( Proto-Malay ) in Malaya . They are Jakun , Orang Kanaq , Orang Seletar , and Temuan . The other Malayic languages, included in neither of these groups, are associated with the expansion of the Malays across the archipelago. They include Riau-Johor Malay ( Malaysian and Indonesian ), Kedah Malay , Kedayan/Brunei Malay , Berau Malay , Bangka Malay , Jambi Malay , Kutai Malay , Natuna Malay, Riau Malay , Loncong , Pattani Malay , and Banjarese . Menterap may belong here. There are also several Malay-based creole languages , such as Betawi , Cocos Malay , Makassar Malay , Ambonese Malay , Dili Malay , Kupang Malay , Manado Malay , Papuan Malay , Pattani Malay , Satun Malay , Songkhla Malay , Bangkok Malay , and Sabah Malay , which may be more or less distinct from standard (Malaccan) Malay. Due to
10863-469: The Mediterranean population had never been large due to geographical factors and climate changes . The Mediterranean is the region where the Dugongidae originated in the mid-late Eocene , along with Caribbean Sea . Dugongs are long-lived, and the oldest recorded specimen reached age 73. They have few natural predators, although animals such as crocodiles, killer whales, and sharks pose a threat to
11016-528: The North American coast. In comparison to cetaceans, sirenians, and pinnipeds, which entered the water approximately 50, 40, and 20 mya, respectively, the sea otter is a relative newcomer to marine life. In some respects though, the sea otter is more fully adapted to water than pinnipeds, which must haul out on land or ice to give birth. Polar bears are thought to have diverged from a population of brown bears , Ursus arctos , that became isolated during
11169-763: The Pacific Islands. The dugong's current distribution is fragmented, and many populations are believed to be close to extinction. The IUCN lists the dugong as a species vulnerable to extinction, while the Convention on International Trade in Endangered Species limits or bans the trade of derived products. Despite being legally protected in many countries, the main causes of population decline remain anthropogenic and include fishing-related fatalities, habitat degradation, and hunting. With its long lifespan of 70 years or more and slow rate of reproduction,
11322-642: The Philippines regarding marine trash are harming the coastal environment not only in Palawan but also across the islands of the Philippines . The first documented sighting in Sarangani Bay occurred in July 2024. Populations also exist around the Solomon Islands and New Caledonia , stretching to an easternmost population in Vanuatu . A highly isolated population lives around the islands of Palau . A single dugong lives at Cocos (Keeling) Islands although
11475-581: The Philippines, and Vietnam. Further disappearances are likely. Dugongs are generally found in warm waters around the coast with large numbers concentrated in wide and shallow protected bays. The dugong is the only strictly marine herbivorous mammal, as all species of manatee utilise fresh water to some degree. Nonetheless, they can tolerate the brackish waters found in coastal wetlands, and large numbers are also found in wide and shallow mangrove channels and around leeward sides of large inshore islands, where seagrass beds are common. They are usually located at
11628-681: The actual ancestor of Classical Malay. Old Malay was influenced by Sanskrit, the classical language of India . Sanskrit loan words can be found in Old Malay vocabulary. The earliest known stone inscription in the Old Malay language was found in Sumatra , Indonesia, written in the Pallava variety of the Grantha alphabet and is dated 1 May 683. Known as the Kedukan Bukit inscription , it
11781-487: The animal forward and can be twisted to turn. The forelimbs are paddle-like flippers which aid in turning and slowing. The dugong lacks nails on its flippers, which are only 15% of a dugong's body length. The tail has deep notches. A dugong's brain weighs a maximum of 300 g (11 oz), about 0.1% of the animal's body weight. With very small eyes, dugongs have limited vision, but acute hearing within narrow sound thresholds. Their ears, which lack pinnae , are located on
11934-537: The animal from the island of Leyte in the Philippines . The name ultimately derives from Proto-Malayo-Polynesian *duyuŋ. Despite common misconception , the term does not come from Malay duyung and it does not mean "lady of the sea" ( Mermaid ). Other common local names include "sea cow", "sea pig" and "sea camel". It is known as the balguja by the Wunambal people of the Mitchell Plateau area in
12087-497: The animal is thought to be a vagrant. Today, possibly the smallest and northernmost population of dugongs exists around the Ryukyu islands, and a population formerly existed off Taiwan. An endangered population of 50 or fewer dugongs, possibly as few as three individuals, survives around Okinawa . New sightings of a cow and calf have been reported in 2017, indicating a possible breeding had occurred in these waters. A single individual
12240-523: The anthropologist A. Asbjørn Jøn has noted, they are often considered the inspiration for mermaids , and people around the world developed cultures around dugong hunting. In some areas, it remains an animal of great significance, and a growing ecotourism industry around dugongs has had an economic benefit in some countries. There is a 5,000-year-old wall painting of a dugong, apparently drawn by Neolithic peoples, in Tambun Cave , Ipoh , Malaysia. This
12393-493: The area from other males, a practice known as lekking . In other areas many males will attempt to mate with the same female, sometimes inflicting injuries to the female or each other. During this, the female will have copulated with multiple males, who will have fought to mount her from below. This greatly increases the chances of conception. Females give birth after a 13- to 15-month gestation , usually to just one calf. Birth occurs in very shallow water, with occasions known where
12546-519: The area has not fully vegetated. Only certain seagrass meadows are suitable for dugong consumption, due to the dugong's highly specialized diet. There is evidence that dugongs actively alter seagrass species compositions at local levels. Dugongs may search out deeper seagrass. Feeding trails have been observed as deep as 33 metres (108 ft), and dugongs have been seen feeding as deep as 37 metres (121 ft). Dugongs are relatively slow-moving, swimming at around 10 km/h (3 m/s). When moving along
12699-461: The cetaceans genetically and morphologically fall firmly within the Artiodactyla (even-toed ungulates). The term "Cetartiodactyla" reflects the idea that whales evolved within the ungulates. The term was coined by merging the name for the two orders, Cetacea and Artiodactyla, into a single word. Under this definition, the closest living land relative of the whales and dolphins is thought to be
12852-555: The colonial language, Dutch, is no longer commonly spoken. (In East Timor , which was governed as a province of Indonesia from 1976 to 1999, Indonesian is widely spoken and recognized under its Constitution as a 'working language'.) Besides Indonesian , which developed from the Riau Malay dialect, there are many Malay varieties spoken in Indonesia; they are divided into western and eastern groups. Western Malay dialects are predominantly spoken in Sumatra and Borneo , which itself
13005-747: The constitution as one of two working languages (the other being English ), alongside the official languages of Tetum and Portuguese . The extent to which Malay is used in these countries varies depending on historical and cultural circumstances. Malay is the national language in Malaysia by Article 152 of the Constitution of Malaysia , and became the sole official language in Peninsular Malaysia in 1968 and in East Malaysia gradually from 1974. English continues, however, to be widely used in professional and commercial fields and in
13158-516: The court moved to establish the Johor Sultanate, it continued using the classical language; it has become so associated with Dutch Riau and British Johor that it is often assumed that the Malay of Riau is close to the classical language. However, there is no closer connection between Malaccan Malay as used on Riau and the Riau vernacular. Among the oldest surviving letters written in Malay are
13311-412: The densest in the animal kingdom , may act as a ballast to help keep sirenians suspended slightly below the water's surface. An adult's length rarely exceeds 3 metres (10 ft). An individual this long is expected to weigh around 420 kilograms (930 lb). Weight in adults is typically more than 250 kilograms (550 lb) and less than 900 kilograms (1,980 lb). The largest individual recorded
13464-521: The diversity in anatomy seen between groups, improved foraging efficiency has been the main driver in their evolution . The level of dependence on the marine environment varies considerably with species. For example, dolphins and whales are completely dependent on the marine environment for all stages of their life; seals feed in the ocean but breed on land; and polar bears must feed on land. The cetaceans became aquatic around 50 million years ago (mya). Based on molecular and morphological research,
13617-479: The dugong is especially vulnerable to extinction. Dugongs are part of the Sirenia order of placental mammals which comprises modern "sea cows" ( manatees as well as dugongs) and their extinct relatives. Sirenia 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 (early Eocene -recent). They attained modest diversity during
13770-463: The dugong's teeth do not continually grow back via horizontal tooth replacement. The dugong has two incisors ( tusks ) which emerge in males during puberty. The female's tusks continue to grow without emerging during puberty, sometimes erupting later in life after reaching the base of the premaxilla . The number of growth layer groups in a tusk indicates the age of a dugong, and the cheek teeth move forward with age. The full dental formula of dugongs
13923-486: The early settlement of a Cape Malay community in Cape Town , who are now known as Coloureds , numerous Classical Malay words were brought into Afrikaans . The extent to which Malay and related Malayan languages are used in the countries where it is spoken varies depending on historical and cultural circumstances. Malay is the national language in Malaysia by Article 152 of the Constitution of Malaysia , and became
14076-474: The eastern part of the Malay or Nusantara archipelago and include Makassar Malay , Manado Malay , Ambonese Malay , North Moluccan Malay , Kupang Malay , Dili Malay , and Papuan Malay . The differences among both groups are quite observable. For example, the word kita means 'we, us' in western, but means 'I, me' in Manado, whereas 'we, us" in Manado is torang and Ambon katong (originally abbreviated from Malay kita orang 'we people'). Another difference
14229-446: The eruption of tusks in the male since tusks erupt in males when testosterone levels reach a high enough level. The age when a female first gives birth is disputed, with some studies placing the age between ten and seventeen years, while others place it as early as six years. There is evidence that male dugongs lose fertility at older ages. Despite the longevity of the dugong, which may live for 50 years or more, females give birth only
14382-590: The far southern parts of the Philippines . They have traditionally been classified as Malay, Para-Malay, and Aboriginal Malay, but this reflects geography and ethnicity rather than a proper linguistic classification. The Malayic languages are mutually intelligible to varying extents, though the distinction between language and dialect is unclear in many cases. Para-Malay includes the Malayic languages of Sumatra . They are: Minangkabau , Central Malay (Bengkulu), Pekal , Talang Mamak , Musi (Palembang), Negeri Sembilan (Malaysia), and Duano’ . Aboriginal Malay are
14535-812: The floor or to stay submerged. Surface-living animals (such as sea otters) need the opposite, and free-swimming animals living in open waters (such as dolphins) need to be neutrally buoyant in order to be able to swim up and down the water column. Typically, thick and dense bone is found in bottom feeders and low bone density is associated with mammals living in deep water. Some marine mammals, such as polar bears and otters, have retained four weight-bearing limbs and can walk on land like fully terrestrial animals. All cetaceans are carnivorous and predatory . Toothed whales mostly feed on fish and cephalopods , followed by crustaceans and bivalves . Some may forage with other kinds of animals, such as other species of whales or certain species of pinnipeds . One common feeding method
14688-454: The globe, but their distribution is patchy and coincides with the productivity of the oceans. Species richness peaks at around 40° latitude, both north and south. This corresponds to the highest levels of primary production around North and South America , Africa , Asia and Australia . Total species range is highly variable for marine mammal species. On average most marine mammals have ranges which are equivalent or smaller than one-fifth of
14841-800: The health of coastal ecosystems, and similar changes have been observed as sea otter populations recovered in the Aleutian and Commander Islands and the Big Sur coast of California. However, some kelp forest ecosystems in California have also thrived without sea otters, with sea urchin populations apparently controlled by other factors. The role of sea otters in maintaining kelp forests has been observed to be more important in areas of open coast than in more protected bays and estuaries . Malay language Malay ( / m ə ˈ l eɪ / mə- LAY ; Malay: Bahasa Melayu , Jawi : بهاس ملايو )
14994-521: The highlands of Sumatra , Indonesia . Terengganu Inscription Stone (Malay: Batu Bersurat Terengganu ; Jawi: باتو برسورت ترڠݢانو) is a granite stele carrying inscription in Jawi script that was found in Terengganu, Malaysia is the earliest evidence of classical Malay inscription. The inscription, dated possibly to 702 AH (corresponds to 1303 CE), constituted the earliest evidence of Jawi writing in
15147-529: The ice further north that remains frozen year-round. Seals may also migrate to other environmental changes, such as El Niño , and traveling seals may use various features of their environment to reach their destination including geomagnetic fields, water and wind currents, the position of the sun and moon and the taste and temperature of the water. Baleen whales famously migrate very long distances into tropical waters to give birth and raise young, possibly to prevent predation by killer whales. The gray whale has
15300-435: The inability of seagrass beds to support large populations. Gatherings of hundreds of dugongs sometimes happen, but they last only for a short time. Because they are shy and do not approach humans, little is known about dugong behavior. They can go six minutes without breathing (though about two and a half minutes is more typical), and have been known to rest on their tails to breathe with their heads above water. They can dive to
15453-560: The language is sometimes called Malacca, Johor or Riau Malay (or various combinations of those names) to distinguish it from the various other Malayic languages . According to Ethnologue 16, several of the Malayic varieties they currently list as separate languages, including the Orang Asli varieties of Peninsular Malay , are so closely related to standard Malay that they may prove to be dialects. There are also several Malay trade and creole languages (e.g. Ambonese Malay ) based on
15606-763: The languages' words for kinship, health, body parts and common animals. Numbers, especially, show remarkable similarities. Within Austronesian, Malay is part of a cluster of numerous closely related forms of speech known as the Malayic languages , which were spread across Malaya and the Indonesian archipelago by Malay traders from Sumatra. There is disagreement as to which varieties of speech popularly called "Malay" should be considered dialects of this language, and which should be classified as distinct Malay languages. The vernacular of Brunei— Brunei Malay —for example,
15759-610: The last reported sightings were made in Kenting National Park in the 1950s and 60s. There had been occasional records of vagrants at the Northern Mariana Islands before 1985. It is unknown how much mixing there was between these populations historically. Some theorize that populations existed independently, for example, that the Okinawan population was isolated members derived from the migration of
15912-463: The late 1960s, herds of up to 500 dugongs were observed off the coast of East Africa and nearby islands. Current populations in this area are extremely small, numbering 50 and below, and it is thought likely they will become extinct. The eastern side of the Red Sea is home to large populations numbering in the hundreds, and similar populations are thought to exist on the western side. In the 1980s, it
16065-460: The letters from Sultan Abu Hayat of Ternate , Maluku Islands in present-day Indonesia , dated around 1521–1522. The text is addressed to the king of Portugal , following contact with Portuguese explorer Francisco Serrão . The letters show sign of non-native usage; the Ternateans used (and still use) the unrelated Ternate language , a West Papuan language , as their first language . Malay
16218-533: The lineages stretches from Moreton Bay to Western Australia , while the other only stretches from Moreton Bay to the Northern Territory . There is not yet sufficient genetic data to make clear boundaries between distinct groups. The dugong's body is large with a cylindrical shape that tapers at both ends. It has thick, smooth skin that is a pale cream colour at birth, but darkens dorsally and laterally to brownish-to-dark-grey with age. The colour of
16371-499: The local marine trash problem in the archipelago remained unabated and became the biggest threat to the already dwindling population of Dugongs in the country. Litters of plastic waste (single-use sachets, plastic bottles , fast food to-go containers, etc.) and other non-biodegradable materials abound in the coastal areas. As these materials may be mistaken as food by dugongs, these may lead to death due to plastic ingestion. Overpopulation and lack of education of all coastal fisherfolk in
16524-576: The longest recorded migration of any mammal, with one traveling 14,000 miles (23,000 km) from the Sea of Okhotsk to the Baja Peninsula . During the winter, manatees living at the northern end of their range migrate to warmer waters. Marine mammals have a number of physiological and anatomical features to overcome the unique challenges associated with aquatic living. Some of these features are very species-specific. Marine mammals have developed
16677-401: The lower stems of kelp , causing the kelp to drift away and die. Loss of the habitat and nutrients provided by kelp forests leads to profound cascade effects on the marine ecosystem. North Pacific areas that do not have sea otters often turn into urchin barrens , with abundant sea urchins and no kelp forest. Reintroduction of sea otters to British Columbia has led to a dramatic improvement in
16830-476: The majority of their time in the water but need to return to land for important activities such as mating , breeding and molting . Sea otters tend to live in kelp forests and estuaries. In contrast, the polar bear is mostly terrestrial and only go into the water on occasions of necessity, and are thus much less adapted to aquatic living. The diets of marine mammals vary considerably as well; some eat zooplankton , others eat fish, squid, shellfish, or seagrass, and
16983-475: The misconception that the word "dugong" itself means "lady of the sea". A common belief found in the Philippines, Malaysia , Indonesia , and Thailand , is that dugongs were originally human or part-human (usually women), and that they cry when they are butchered or beached . Because of this, it is considered bad luck if a dugong is killed or accidentally dies in nets or fish corrals in the Philippines, some parts of Sabah (Malaysia), and northern Sulawesi and
17136-797: The most valuable foods of Australian Aboriginals and Torres Strait Islanders . Some Aboriginals regard dugongs as part of their Aboriginality. Marine mammal Marine mammals are mammals that rely on marine (saltwater) ecosystems for their existence. They include animals such as cetaceans ( whales , dolphins and porpoises ), pinnipeds ( seals , sea lions and walruses ), sirenians ( manatees and dugongs ), sea otters and polar bears . They are an informal group, unified only by their reliance on marine environments for feeding and survival. Marine mammal adaptation to an aquatic lifestyle varies considerably between species. Both cetaceans and sirenians are fully aquatic and therefore are obligate water dwellers. Pinnipeds are semiaquatic; they spend
17289-556: The mothers were almost on the shore. As soon as the young is born the mother pushes it to the surface to take a breath. Newborns are already 1.2 metres (4 ft) long and weigh around 30 kilograms (65 lb). Once born, they stay close to their mothers, possibly to make swimming easier. The calf nurses for 14–18 months, although it begins to eat seagrasses soon after birth. A calf will only leave its mother once it has matured. Dugongs have historically provided easy targets for hunters, who killed them for their meat, oil, skin, and bones. As
17442-483: The national language ( bahasa kebangsaan or bahasa nasional ) of several nation states with various official names: in Malaysia, it is designated as either Bahasa Malaysia (" Malaysian ") or also Bahasa Melayu ("Malay language"); in Singapore and Brunei, it is called Bahasa Melayu ("Malay language"); in Indonesia, an autonomous normative variety called Bahasa Indonesia (" Indonesian language ")
17595-496: The north of the Northern Territory , with a population of over 20,000 in the Gulf of Carpentaria alone. A population of over 25,000 exists in the Torres Strait such as off Thursday Island , although there is significant migration between the strait and the waters of New Guinea . The Great Barrier Reef provides important feeding areas for the species; this reef area houses a stable population of around 10,000, although
17748-541: The oceans, which have also evolved several specialized aquatic traits. In addition to the above, several other mammals have a great dependency on the sea without having become so anatomically specialized, otherwise known as "quasi-marine mammals". This term can include: the greater bulldog bat ( Noctilio leporinus ), the fish-eating bat ( Myotis vivesi ), the arctic fox ( Vulpes lagopus ) which often scavenges polar bear kills, coastal gray wolf ( Canis lupus ) populations which predominantly eat salmon and marine carcasses,
17901-858: The ongoing effects of global warming degrade Arctic environments. Procaviidae Elephantidae Dugongidae (dugongs) Trichechus manatus (West Indian manatee) Trichechus senegalensis (African manatee) Trichechus inunguis (Amazonian manatee; freshwater species) Hippopotamidae Mysticeti (baleen whales) Odontoceti (toothed whales, except river dolphins ) Ruminantia Perissodactyla Pholidota Feliformia Canidae Ursus maritimus (polar bear) all other ursids Enhydra lutris (sea otter) Lontra felina (marine otter) † Neogale macrodon (sea mink) all other mustelids Otariidae (eared seals) Odobenidae (walruses) Phocidae (earless seals) The term "marine mammal" encompasses all mammals whose survival depends entirely or almost entirely on
18054-621: The open ocean, and species like the sperm whale may dive to depths of −1,000 to −2,500 feet (−300 to −760 m) in search of food. Sirenians live in shallow coastal waters, usually living 30 feet (9.1 m) below sea level. However, they have been known to dive to −120 feet (−37 m) to forage deep-water seagrasses . Sea otters live in protected areas, such as rocky shores, kelp forests , and barrier reefs , although they may reside among drift ice or in sandy, muddy, or silty areas. Many marine mammals seasonally migrate. Annual ice contains areas of water that appear and disappear throughout
18207-431: The option of answering questions using Jawi. The Latin script, however, is the most commonly used in Brunei and Malaysia, both for official and informal purposes. Historically, Malay has been written using various scripts. Before the introduction of Arabic script in the Malay region, Malay was written using the Pallava , Kawi and Rencong scripts; these scripts are no longer frequently used, but similar scripts such as
18360-541: The polar bear might not be considered a species under some species concepts . In general, terrestrial amniote invasions of the sea have become more frequent in the Cenozoic than they were in the Mesozoic. Factors contributing to this trend include the increasing productivity of near-shore marine environments, and the role of endothermy in facilitating this transition. Marine mammals are widely distributed throughout
18513-544: The population concentration has shifted over time. Large bays facing north on the Queensland coast provide significant habitats for dugong, with the southernmost of these being Hervey Bay and Moreton Bay. Dugongs had been occasional visitors along the Gold Coast where a re-establishment of a local population through range expansions has started recently. The Persian Gulf has the second-largest dugong population in
18666-514: The rapidly growing, higher nutrient seagrasses that dugongs prefer. Dugongs may also prefer to feed on younger, less fibrous strands of seagrasses, and cycles of cultivation feeding at different seagrass meadows may provide them with a greater number of younger plants. Due to their poor eyesight, dugongs often use smell to locate edible plants. They also have a strong tactile sense and feel their surroundings with their long sensitive bristles. They will dig up an entire plant and then shake it to remove
18819-541: The region during the Malacca Sultanate era (1402–1511). It was the period the Malay language developed rapidly under the influence of Islamic literature. The development changed the nature of the language with massive infusion of Arabic , Sanskrit , and Tamil vocabularies, called Classical Malay . Under the Sultanate of Malacca the language evolved into a form recognisable to speakers of modern Malay. When
18972-561: The risk of predation. Deep waters may provide a thermal refuge from cooler waters closer to the shore during winter. Australia is home to the largest population, stretching from Shark Bay in Western Australia to Moreton Bay in Queensland . The population of Shark Bay is thought to be stable with over 10,000 dugongs. Smaller populations exist up the coast, including one in Ashmore Reef . Large numbers of dugongs live to
19125-403: The sand before eating it. They have been known to collect a pile of plants in one area before eating them. The flexible and muscular upper lip is used to dig out the plants. This leaves furrows in the sand in their path. A dugong reaches sexual maturity between the ages of eight and eighteen, older than in most other mammals. The way that females know how a male has reached sexual maturity is by
19278-426: The seabed to feed they walk on their pectoral fins. Dugong feeding may favor the subsequent growth of low-fibre, high-nitrogen seagrasses such as Halophilia and Halodule. Species such as Zosteria capricorni are more dominant in established seagrass beds, but grow slowly, while Halophilia and Halodule grow quickly in the open space left by dugong feeding. This behavior is known as cultivation grazing and favors
19431-406: The sides of their head. The nostrils are located on top of the head and can be closed using valves. Dugongs have two teats , one located behind each flipper. There are few differences between the sexes; the body structures are almost the same. A male's testes are not externally located, and the main difference between males and females is the location of the genital aperture to the umbilicus and
19584-590: The sole official language in West Malaysia in 1968, and in East Malaysia gradually from 1974. English continues, however, to be widely used in professional and commercial fields and in the superior courts. Other minority languages are also commonly used by the country's large ethnic minorities. The situation in Brunei is similar to that of Malaysia. In Singapore, Malay was historically the lingua franca among people of different nationalities. Although this has largely given way to English, Malay still retains
19737-435: The status of national language and the national anthem , Majulah Singapura , is entirely in Malay. In addition, parade commands in the military, police and civil defence are given only in Malay. Most residents of the five southernmost provinces of Thailand —a region that, for the most part, used to be part of an ancient Malay kingdom called Pattani —speak a dialect of Malay called Yawi (not to be confused with Jawi), which
19890-635: The summer of 2019. In Vietnam, dugongs have been restricted mostly to the provinces of Kiên Giang and Bà Rịa–Vũng Tàu , including Phu Quoc Island and Con Dao Island , which hosted large populations in the past. Con Dao is now the only site in Vietnam where dugongs are regularly seen, protected within the Côn Đảo National Park . Nonetheless, dangerously low levels of attention to the conservation of marine organisms in Vietnam and Cambodia may result in increased intentional or unintentional catches, and illegal trade
20043-548: The superior courts. Other minority languages are also commonly used by the country's large ethnic minorities. The situation in Brunei is similar to that in Malaysia. In the Philippines , Indonesian is spoken by the overseas Indonesian community concentrated in Davao City . Functional phrases are taught to members of the Armed Forces of the Philippines as well as local students. Malay, like most Austronesian languages,
20196-463: The supply of their choice grasses decreases. In other southern areas of both western and eastern Australia, there is evidence that dugongs actively seek out large invertebrates. This does not apply to dugongs in tropical areas, in which fecal evidence indicates that invertebrates are not eaten. Most dugongs do not feed on lush areas, but where the seagrass is more sparse. Additional factors such as protein concentration and regenerative ability also affect
20349-420: The target for commercial industry, leading to a sharp decline in all populations of exploited species, such as whales and seals. Commercial hunting led to the extinction of the Steller's sea cow , sea mink , Japanese sea lion and Caribbean monk seal . After commercial hunting ended, some species, such as the gray whale and northern elephant seal , have rebounded in numbers; conversely, other species, such as
20502-484: The value of a seagrass bed. The chemical structure and composition of the seagrass are important, and the grass species most often eaten are low in fiber, high in nitrogen, and easily digestible. In the Great Barrier Reef, dugongs feed on low-fiber high-nitrogen seagrass such as Halophila and Halodule , to maximize nutrient intake instead of bulk eating. Seagrasses of a lower seral are preferred, where
20655-459: The water. Polar bears, otters, and fur seals have long, oily, and waterproof fur in order to trap air to provide insulation. In contrast, other marine mammals—such as whales, dolphins, porpoises, manatees, dugongs, and walruses—have lost long fur in favor of a thick, dense epidermis and a thickened fat layer (blubber) to prevent drag . Wading and bottom-feeding animals (such as manatees) need to be heavier than water in order to keep contact with
20808-405: The waters of 37 countries and territories. Recorded numbers of dugongs are generally believed to be lower than actual numbers, due to a lack of accurate surveys. Despite this, the dugong population is thought to be shrinking, with a worldwide decline of 20 percent in the last 90 years. They have disappeared from the waters of Hong Kong , Mauritius , and Taiwan, as well as parts of Cambodia , Japan,
20961-447: The waters of large inshore islands and inter-reefal waters. The northern waters of Australia between Shark Bay and Moreton Bay are believed to be the dugong's contemporary stronghold. Like all modern sirenians, the dugong has a fusiform body with no dorsal fin or hind limbs . The forelimbs or flippers are paddle-like. The dugong is easily distinguishable from the manatees by its fluked, dolphin-like tail; moreover, it possesses
21114-742: The west coast of the island of Hainan . Historically, dugongs were also present in the southern parts of the Yellow Sea . The last confirmed record of dugongs in Chinese waters was documented in 2008. In August 2022, an article published on the Royal Society Open Science concluded that dugongs were functionally extinct in China, which was based on a large-scale interview survey conducted across four southern Chinese maritime provinces ( Hainan , Guangxi , Guangdong , and Fujian ) in
21267-555: The west of the gulf in recent years, and the remaining population in the east is thought to be very small and possibly declining. Dugongs are believed to exist in the Straits of Johor in very small numbers. The waters around Borneo support a small population, with more scattered throughout the Malay Archipelago . All the islands of the Philippines once provided habitats for sizeable herds of dugongs. They were common until
21420-409: The whale's interest, be within a certain size range so that the baleen plates can filter it, and be slow enough so that it cannot escape. Otters are the only marine animals that are capable of lifting and turning over rocks, which they often do with their front paws when searching for prey. The sea otter may pluck snails and other organisms from kelp and dig deep into underwater mud for clams . It
21573-559: The whole plant, including the roots, although when this is impossible they will feed on just the leaves. A wide variety of seagrass has been found in dugong stomach contents, and evidence exists they will eat algae when seagrass is scarce. Although almost completely herbivorous , they will occasionally eat invertebrates such as jellyfish , sea squirts , and shellfish . Dugongs in Moreton Bay, Australia, are omnivorous, feeding on invertebrates such as polychaetes or marine algae when
21726-462: The world, inhabiting most of the southern coast, and the current population is believed to range from 5,800 to 7,300. In the course of a study carried out in 1986 and 1999 on the Persian Gulf, the largest reported group sighting was made of more than 600 individuals to the west of Qatar . A 2017 study found a nearly 25% drop in population since 1950. Reasons for this drastic population loss include illegal poaching, oil spills , and net entanglement. In
21879-483: The year as the weather changes, and seals migrate in response to these changes. In turn, polar bears must follow their prey. In Hudson Bay , James Bay , and some other areas, the ice melts completely each summer (an event often referred to as "ice-floe breakup"), forcing polar bears to go onto land and wait through the months until the next freeze-up. In the Chukchi and Beaufort seas, polar bears retreat each summer to
22032-490: The young, and a dugong has also been recorded to have died from trauma after being impaled by a stingray barb. A large number of infections and parasitic diseases affect dugongs. Detected pathogens include helminths , cryptosporidium , different types of bacterial infections, and other unidentified parasites. 30% of dugong deaths in Queensland since 1996 are thought to be because of disease. Although they are social animals , they are usually solitary or found in pairs due to
22185-462: Was 4.06 metres (13 ft 4 in) long and weighed 1,016 kilograms (2,240 lb), and was found off the Saurashtra coast of west India . Females tend to be larger than males. Dugongs are found in warm coastal waters from the western Pacific Ocean to the eastern coast of Africa, along an estimated 140,000 kilometres (87,000 mi) of coastline between 26° and 27° to the north and south of
22338-513: Was discovered by Lieutenant R.L. Rawlings in 1959 while on a routine patrol. Dugongs feature in Southeast Asian, especially Austronesian , folklore . In languages like Ilocano , Mapun , Yakan , Tausug , and Kadazan Dusun of the Philippines and Sabah , the name for dugongs is a synonym for "mermaid". In Malay , they are sometimes referred to as perempoen laut ("woman of the sea") or putri duyong ("dugong princess"), leading to
22491-568: Was discovered by the Dutchman M. Batenburg on 29 November 1920 at Kedukan Bukit, South Sumatra , on the banks of the Tatang, a tributary of the Musi River . It is a small stone of 45 by 80 centimetres (18 by 31 in). For centuries, Srivijaya , through its expansion, economic power and military prowess, was responsible for the widespread of Old Malay throughout the Malay Archipelago . It
22644-707: Was estimated there could be as many as 4,000 dugongs in the Red Sea. Dugong populations in Madagascar are poorly studied, but due to widespread exploitation, it is thought they may have severely declined, with few surviving individuals. The resident population around Mayotte is thought to number just 10 individuals. In Mozambique , most of the remaining local populations are very small and the largest (about 120 individuals) occurs at Bazaruto Island , but they have become rare in historical habitats such as in Maputo Bay and on Inhaca Island . The Bazaruto Island population
22797-456: Was gradually replaced by the Rumi script. Malay is spoken in Brunei , Indonesia , Malaysia , East Timor , Singapore and southern Thailand . Indonesia regulates its own normative variety of Malay, while Malaysia and Singapore use a common standard. Brunei, in addition to Standard Malay, uses a distinct vernacular dialect called Brunei Malay . In East Timor , Indonesian is recognised by
22950-544: Was recorded at Amami Ōshima , at the northernmost edge of the dugong's historic range, more than 40 years after the last previous recorded sighting. A vagrant strayed into a port near Ushibuka, Kumamoto, and died due to poor health. Historically, the Yaeyama Islands held a large concentration of dugongs, with more than 300 individuals. On the Aragusuku Islands , large quantities of skulls are preserved at
23103-412: Was seen as far south as Sydney . Although they are marine creatures, dugongs have been known to travel up creeks, and in one case a dugong was caught fifteen kilometres (8 nmi) up a creek near Cooktown . Dugongs, along with other sirenians , are referred to as "sea cows" because their diet consists mainly of seagrass , particularly the genera Halophila and Halodule . When eating they ingest
23256-621: Was the working language of traders and it was used in various ports, and marketplaces in the region. Other evidence is the Tanjung Tanah Law in post-Pallava letters. This 14th-century pre-Islamic legal text was produced in the Adityawarman era (1345–1377) of Dharmasraya , a Hindu-Buddhist kingdom that arose after the end of Srivijayan rule in Sumatra . The laws were for the Minangkabau people , who today still live in
23409-810: Was used solely as a lingua franca for inter-ethnic communications. Malay is a member of the Austronesian family of languages, which includes languages from Southeast Asia and the Pacific Ocean , with a smaller number in continental Asia . Malagasy , a geographic outlier spoken in Madagascar in the Indian Ocean , is also a member of this language family. Although these languages are not necessarily mutually intelligible to any extent, their similarities are often quite apparent. In more conservative languages like Malay, many roots have come with relatively little change from their common ancestor, Proto-Austronesian language . There are many cognates found in
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