Dugong

The dugong (Template:IPAc-en; 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 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, 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; it also possesses 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 parts of its modern range, particularly northern Australia and 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 it 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, the dugong is especially vulnerable to extinction.

Evolution

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 the Oligocene and Miocene but subsequently declined as a result of climatic cooling, oceanographic changes, and human interference.<ref>Template:Cite book</ref>

Etymology and taxonomy

The word "dugong" derives from the Visayan (probably Cebuano) Template:Lang.<ref name="buffon">Template:Cite book</ref><ref name="mw">Template:Cite web</ref><ref name="weekley">Template:Cite book</ref> 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 the animal from the island of Leyte in the Philippines.<ref name="buffon"/><ref name="weekley"/><ref name="burnell">Template:Cite book</ref> The name ultimately derives from Proto-Malayo-Polynesian *duyuŋ. Despite a common misconception, the term does not come from Malay Template:Lang and it does not mean "lady of the sea" (mermaid).<ref name="Blust">Template:Cite web</ref>

Other common local names include "sea cow", "sea pig", and "sea camel".<ref name="Audubon">Reeves, R. R. (2002). National Audubon Society Guide to Marine Mammals of the World. Knopf. Template:ISBN. pp. 478–481</ref> It is known as the balguja by the Wunambal people of the Mitchell Plateau area in the Kimberley, Western Australia.<ref name="Bush Heritage Australia">Template:Cite web</ref>

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.<ref name="IUCNpdf">Marsh, H. et al. (2002). Dugong: status reports and action plans for countries and territories Template:Webarchive. IUCN.</ref> It was first classified by Müller in 1776 as Trichechus dugon,<ref name="paleo5">Template:Cite web</ref> a member of the manatee genus previously defined by Linnaeus.<ref name="paleo2">Template:Cite web</ref> It was later assigned as the type species of Dugong by Lacépède<ref name=paleo3>Dugong . The Paleobiology Database. Retrieved on 22 July 2007.</ref> and further classified within its own family by Gray<ref name="paleo4">Template:Cite web</ref> and subfamily by Simpson.<ref name="paleo5"/>

Dugongs and other sirenians are not closely related to other marine mammals, being more closely related to elephants.<ref name="Sydney"/> Dugongs and elephants share a monophyletic group with hyraxes and the aardvark, one of the earliest offshoots of eutherians. The fossil record shows sirenians appearing in the Eocene, when 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 the Miocene. The Steller's sea cow became extinct in the 18th century. No fossils exist of other members of the Dugongidae.<ref name=AussieFauna/>

Molecular studies have been conducted on dugong populations using mitochondrial DNA. The results have suggested that the population in 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.<ref name="IUCNpdf"/> One of the lineages stretches from Moreton Bay to Western Australia, while the other only stretches from Moreton Bay to the Northern Territory.<ref name="Sydney"/> There is not yet sufficient genetic data to make clear the boundaries between distinct groups.<ref name="IUCNpdf"/>

Anatomy and morphology

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 a dugong can change due to the growth of algae on the skin.<ref name="ADW">Template:Cite web</ref>

An adult's length rarely exceeds Template:Convert. An individual this long is expected to weigh around Template:Convert. Weight in adults is typically more than Template:Convert and less than Template:Convert.<ref name="Burnie">Burnie D and Wilson DE (Eds.), Animal: The Definitive Visual Guide to the World's Wildlife. DK Adult (2005), Template:ISBN</ref> The largest individual recorded was Template:Convert long and weighed Template:Convert,<ref name=AussieFauna/> and was found off the Saurashtra coast of west India.<ref>Wood, Gerald (1983) The Guinness Book of Animal Facts and Feats. Sterling Pub Co Inc. Template:ISBNTemplate:Page?</ref> Females tend to be larger than males.<ref name=AussieFauna/>

The body is sparsely covered in short hair, a common feature among sirenians which may allow for tactile interpretation of their environment.<ref name="BBE">Template:Cite journal</ref> These hairs are most developed around the mouth, which has a large horseshoe-shaped upper lip forming a highly mobile muzzle.<ref name=AussieFauna/> This muscular upper lip aids the dugong in foraging.<ref name="ADW"/>

Diagram of the bones in a dugong forelimb at different stages of life

Bones in the forelimb can fuse variously with age.

The dugong's tail flukes<ref name="NatGeo">Template:Cite web</ref> and flippers<ref name="Sydney">Template:Citation</ref> are similar to those of dolphins. These flukes are raised up and down in long strokes to move the animal forward and can be twisted to turn. The forelimbs are paddle-like flippers which aid in turning and slowing.<ref name=AussieFauna/> The dugong lacks nails on its flippers, which are only 15% of a dugong's body length.<ref name=AussieFauna/> The tail has deep notches.<ref name=animaldiversity>Myers, P. (2002). Dugongidae Template:Webarchive. University of Michigan Museum of Zoology. Retrieved on 10 March 2007.</ref>

A dugong's brain weighs a maximum of Template:Cvt, about 0.1% of the animal's body weight.<ref name=AussieFauna/> With very small eyes,<ref name="CaseStudy">Template:Cite web</ref> dugongs have limited vision, but acute hearing within narrow sound thresholds. Their ears, which lack pinnae, are located on the sides of their head. The nostrils are located on top of the head and can be closed using valves.<ref name="Sydney"/> Dugongs have two teats, one located behind each flipper.<ref name=AussieFauna/> There are few differences between the sexes; the body structures are almost the same.<ref name="ADW"/> 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 the anus.<ref>Template:Cite journal</ref> 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.<ref name=AussieFauna/> If the dugong is wounded, its blood will clot rapidly.<ref name="ADW"/>

File:Dugong dugon fin egypt.jpg

Dugong tail fluke

The skull of a dugong is unique.<ref name=animaldiversity/> The skull is enlarged with a sharply down-turned premaxilla, which is stronger in males. The spine has between 57 and 60 vertebrae.<ref name=AussieFauna/> Unlike in manatees, the dugong's teeth do not continually grow back via horizontal tooth replacement.<ref name="evolutionpdf">Template:Citation</ref> 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.<ref name=AussieFauna>Marsh, Helene. "Chapter 57: Dugongidae". Fauna of Australia: Vol. 1B Mammalia. CSIRO. Template:ISBN.</ref> The number of growth layer groups in a tusk indicates the age of a dugong,<ref name="IUCNpdf"/> and the cheek teeth move forward with age.<ref name=animaldiversity/>

The full dental formula of dugongs is Template:DentalFormula, 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.<ref name=animaldiversity/> 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 the densest in the animal kingdom,<ref name=SeaLife>Waller, Geoffrey and Dando, Marc (1996). Sealife: A Complete Guide to the Marine Environment. Smithsonian Institution. Template:ISBN. pp. 413–420</ref> may act as a ballast to help keep sirenians suspended slightly below the water's surface.<ref name="ADW2">Template:Cite web</ref>

Distribution and habitat

Dugong on its side stirring up sand

Dugong on the sea floor at Marsa Alam, Egypt

Dugongs are found in warm coastal waters from the western Pacific Ocean to the eastern coast of Africa,<ref name="NatGeo"/> along an estimated Template:Convert of coastline<ref name="iucn">Template:Cite iucn</ref> between 26° and 27° to the north and south of the equator.<ref name="IUCNpdf"/> 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,<ref name="IUCNpdf"/> which is highly fractured.<ref name="ADW"/> Their distributions during warmer periods of Holocene might have been broader than today.<ref>Erich Fitzgerald, 2005, Holocene Record of the Dugong (Dugong Dugon) From Victoria, Southeast Australia, Marine Mammal Science, 21, pp. 355–361</ref> Today populations of dugongs are found in the waters of 37 countries and territories.<ref name="Sydney"/> Recorded numbers of dugongs are generally believed to be lower than actual numbers, due to a lack of accurate surveys. Despite this uncertainty, the dugong population is thought to be shrinking,<ref name="IUCNpdf"/> 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, the Philippines, and Vietnam. Further disappearances are likely.<ref name="Sydney"/>

Dugongs are generally found in warm coastal waters<ref name="NatGeo"/> with large numbers concentrated in wide and shallow protected bays.<ref name="IUCNpdf"/> The dugong is the only strictly marine herbivorous mammal, as all species of manatee utilise fresh water to some degree.<ref name="IUCNpdf"/> Nonetheless, they can tolerate the brackish waters found in coastal wetlands,<ref>Naik, Prabir Kumar et al. (2008) "Conservation of Chilika Lake, Orissa, India" Template:Webarchive in Sengupta, M. and Dalwani, R. (Editors) Proceedings of Taal 2007: The 12th World Lake Conference: 1988–1992</ref> 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.<ref name="IUCNpdf"/> They are usually located at a depth of around Template:Cvt,<ref name="ADW"/> although in areas where the continental shelf remains shallow dugongs have been known to travel more than Template:Convert from the shore, descending to as far as Template:Convert, where deepwater seagrasses such as Halophila spinulosa are found.<ref name="IUCNpdf"/> Specific habitats are used for different activities. It has been observed that shallow waters are used as sites for calving, minimizing the risk of predation. Deep waters may provide a thermal refuge from cooler waters closer to the shore during winter.<ref name="IUCNpdf"/>

Australia

Australia is home to the largest population, stretching from Shark Bay in Western Australia to Moreton Bay in Queensland.<ref name="Sydney"/> 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 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.<ref name="IUCNpdf"/>

The Great Barrier Reef provides important feeding areas for the species;<ref>Hogan, C. Michael. (2011). "Coral Sea" Template:Webarchive in Encyclopedia of Earth. Eds. P. Saundry & C.J. Cleveland. National Council for Science and the Environment. Washington DC</ref> this reef area houses a stable population of around 10,000, although 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.<ref name="Sydney"/> Dugongs had been occasional visitors along the Gold Coast<ref>The Center of coastal management in the Griffith University. Discovering our coasts – Dugong Template:Webarchive (pdf). Working for our future – today. Gold Coast City Council. Retrieved on April 19, 2017</ref> where a re-establishment of a local population through range expansions has started recently.<ref>Muir K.. 2017. Dugongs makes Gold Coast waters home after moving south from Moreton Island. The Gold Coast Bulletin via The Advertiser (Adelaide) . Retrieved on April 19, 2017</ref>

Persian Gulf

The Persian Gulf has the second-largest dugong population in the world, inhabiting most of the southern coast,<ref name="IUCNpdf"/> and the current population is believed to range from 5,800 to 7,300.<ref name="reconstructing"/> 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.<ref name="sillitoe">Template:Cite book</ref> A 2017 study found a nearly 25% drop in population since 1950.<ref name="reconstructing">Template:Cite journal</ref> Reasons for this drastic population loss include illegal poaching, oil spills, and net entanglement.<ref name="sillitoe"/>

East Africa and South Asia

In 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 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.<ref>Template:Cite web</ref><ref>Davis ZR P. Madagascar's dugongs on the brink Template:Webarchive. c-3.org.uk</ref> The resident population around Mayotte is thought to number just 10 individuals.<ref name="Cremades">Template:Cite book</ref> In Mozambique, most of the remaining local populations are very small and the largest (about 120 individuals) occurs at Bazaruto Island,<ref>Template:Cite journal</ref> but they have become rare in historical habitats such as in Maputo Bay and on Inhaca Island.<ref>UNESCO. Assessing potential World Heritage marine sites in the Western Indian Ocean – Marine mammals – Dugong, Whales and Dolphins Template:Webarchive. Retrieved on 18 December. 2014</ref><ref>Saving Endangered Dugongs of the Western Indian Ocean Template:Webarchive. dugongs.org</ref> The Bazaruto Island population is possibly the last long-term viable population in East Africa, with only some of its core territory lying within protected waters.<ref name="Trotzuk2022"/>

The East African population is genetically distinct from those of the Red Sea and those off Madagascar.<ref name="Trotzuk2022">Template:Cite journal</ref> In Tanzania, observations have recently increased around the Mafia Island Marine Park where a hunt was intended by fishermen but failed in 2009.<ref name="Wiomsa">Template:Cite web</ref> In the Seychelles, dugongs had been regarded as extinct in the 18th century<ref>Are Dugons extinct on Mauritius? Template:Webarchive. Retrieved on September 04, 2017</ref> 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.<ref>Template:Cite web</ref><ref>Template:Cite journal</ref> 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.<ref>Template:Citation</ref><ref>Template:Cite web</ref>

There are less than 250 individuals scattered throughout Indian waters.<ref name="GOBI2020">Template:Cite web</ref> A highly isolated breeding population exists in the Marine National Park, Gulf of Kutch,<ref>Wells S., Dwivedi N.S., Singh S., Ivan R. Marine Region 10 – Central Indian Ocean Template:Webarchive. p. 19.</ref> the only remaining population in western India. It is Template:Convert from the population in the Persian Gulf, and Template:Convert 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 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-colonizations of the species.<ref>IANS. 2010. Will growing seagrass beds bring back rare sea cows to Chilika? Template:Webarchive. The Thaindian News. Retrieved on April 19, 2017</ref> 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 is now believed to be small and scattered.<ref name="IUCNpdf"/>

Southeast Asia and the West Pacific

Dugong swimming in blue water with a remora attached

Dugong with attached remora off Lamen Island, Vanuatu

A small population existed along the southern coast of China, particularly the Gulf of Tonkin (Beibu Gulf), where efforts were made to protect it,<ref>Template:Cite web</ref> including the establishment of a seagrass sanctuary for dugong and other endangered marine fauna ranging in Guangxi.<ref>Template:Cite report</ref><ref>Template:Cite web</ref> Despite these efforts, numbers continued to decrease, and in 2007 it was reported that no more dugong could be found on the west coast of the island of Hainan.<ref>Template:Cite journal</ref> Historically, dugongs were also present in the southern parts of the Yellow Sea.<ref>Template:Cite web</ref> 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 the summer of 2019.<ref>Template:Cite news</ref><ref>Template:Cite journal</ref>

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,<ref>Marsh, Helene; O'Shea, Thomas J. and Reynolds, John E. (2012) Ecology and Conservation of the Sirenia: Dugongs and Manatees. Cambridge University Press. Template:ISBN. p. 406.</ref> which hosted large populations in the past.<ref name=Adulyanukosol>Template:Cite report</ref> Con Dao is now the only site in Vietnam where dugongs are regularly seen,<ref>Template:Cite report</ref> protected within the Côn Đảo National Park.<ref>Template:Cite web</ref> 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 is a potential danger for local dugongs.<ref name=Adulyanukosol/> On Phu Quoc, the first 'Dugong Festival' was held in 2014, aiming to raise awareness of these issues.<ref name=ThanhNien>Template:Cite news</ref>

In Thailand, the present distribution of dugongs is restricted to six provinces along the Andaman Sea,<ref name="BP-20191014">Template:Cite news</ref> and very few dugongs are present in the Gulf of Thailand.<ref>Adulyanukosol K., Poovachiranon S. (2006) "Dugong (Dugong dugon) and seagrass in Thailand: present status and future challenges. Part II: Dugong – Adulyanukosol & Poovachiranon", pp. 41–50 in Proceedings of the 3rd International Symposium on SEASTAR2000 and Asian Bio-logging Science (The 7th SEASTAR2000 workshop)</ref> The Gulf of Thailand was historically home to a large number of animals, but none have been sighted in the west of the gulf in recent years,<ref name="IUCNpdf"/> and the remaining population in the east is thought to be very small and possibly declining.<ref>Hines, Ellen et al. (2004) "Conservation of the Dugong (Dugong dugon) on the East Coast of the Gulf of Thailand (Thailand & Cambodia)". Final Report to: Ocean Park Conservation Foundation Aberdeen, Hong Kong & Project Aware, Australia</ref> 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.<ref name="IUCNpdf"/>

All the islands of the Philippines once provided habitats for sizeable herds of dugongs. They were common until 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.<ref name="Yan">Template:Cite news</ref><ref>Template:Cite news</ref><ref>Template:Cite webTemplate:Dead link</ref> Recently, 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 the Philippines regarding marine trash are harming the coastal environment not only in Palawan but also across the islands of the Philippines.<ref>Template:Cite news</ref> The first documented sighting in Sarangani Bay occurred in July 2024.<ref>Template:Cite news</ref>

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.<ref name="IUCNpdf"/>

A single dugong lives at Cocos (Keeling) Islands although the animal is thought to be a vagrant.<ref>Template:Cite journal</ref><ref name=ConservationCommonwealth>Template:Cite report</ref>

Northern Pacific

Today, possibly the smallest and northernmost population of dugongs exists around the Ryukyu islands, and a population formerly existed off Taiwan.<ref name="IUCNpdf"/> An endangered population of 50 or fewer dugongs, possibly as few as three individuals, survives<ref>"琉球朝日放送 報道部　ニュースQプラス » 独自 古宇利島沖にジュゴンの姿" Template:Webarchive. 琉球朝日放送 報道部　ニュースQプラス.</ref> around Okinawa.<ref name="Okinawa">Template:Cite web</ref> New sightings of a cow and calf have been reported in 2017, indicating a possible breeding had occurred in these waters.<ref>The Okinawa Times Plus. 2017. ジュゴン、沖縄で新たな目撃情報　「子どもの個体」 Template:Webarchive. The Kyodo News. Retrieved on April 13, 2017</ref> A single individual 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.<ref>"奄美でジュゴン40年ぶり確認/琉大と北大が共同調査" Template:Webarchive. Ryūkyū Shimpō.</ref> A vagrant strayed into a port near Ushibuka, Kumamoto, and died due to poor health.<ref>Template:Cite web</ref> 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 a utaki that outsiders are strictly forbidden to enter.<ref>Template:Cite web</ref><ref>Template:Cite news</ref> 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.

In March 2025 a fisherman accidentally caught a dugong in his nets at Fenniaolin in Yilin County in northeast Taiwan, which he released back into the sea. This was the first sighting of a live dugong in Taiwan waters in 88 years.<ref>Template:Cite news</ref>

Populations around Taiwan appear to be almost extinct, although remnant individuals may visit areas with rich seagrass beds such as Dongsha Atoll.<ref>Hsiao-yun S.. 2013. Featured Project – Removing the Veil of Mystery from the Seagrass Beds of Dongsha Atoll National Park|Dongsha Atoll Template:Webarchive. The National Parks of Taiwan by Taiwan Government. Retrieved on 3 January. 2015</ref> Some of the last reported sightings were made in Kenting National Park in the 1950s and 60s.<ref>Template:Citation</ref> There had been occasional records of vagrants at the Northern Mariana Islands before 1985.<ref>Template:Cite web</ref> 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 a Philippine subspecies.<ref>Template:Cite web</ref> Others postulate that the populations formed part of a super-population where migration between Ryukyu, Taiwan, and the Philippines was common.<ref>"OPRF 海洋政策研究財団 人と海洋の共生をめざして｜ニューズレター｜158号｜八重山にジュゴンをとりもどそう". sof.or.jp.</ref>

Extinct Mediterranean population

It has been confirmed that dugongs once inhabited the water of the Mediterranean<ref>Template:Cite web</ref><ref>Template:Cite web</ref> possibly until after the rise of civilizations along the inland sea. This population possibly shared ancestry with the Red Sea population, and the Mediterranean population had never been large due to geographical factors and climate changes.<ref>Template:Cite web</ref> The Mediterranean is the region where the Dugongidae originated in the mid-late Eocene, along with Caribbean Sea.<ref name=edge/><ref>Template:Cite web</ref>

Ecology and life history

A large dugong swimming towards the right with a smaller dugong half its size hugging its back, both in very shallow water with the surface and seabed just above and below them respectively

A mother and calf in shallow water

Dugongs are long-lived, and the oldest recorded specimen reached age 73.<ref name="IUCNpdf"/> They have few natural predators, although animals such as crocodiles, killer whales, and sharks pose a threat to the young,<ref name="Sydney"/> 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.<ref name="IUCNpdf"/>

Although they are social animals, they are usually solitary or found in pairs due to the inability of seagrass beds to support large populations.<ref name="ADW"/> Gatherings of hundreds of dugongs sometimes happen,<ref name="NatGeo"/> but they last only for a short time.<ref name="ADW"/> Because they are shy and do not approach humans, little is known about dugong behavior.<ref name="ADW"/> They can go six minutes without breathing (though about two and a half minutes is more typical),<ref>Template:Cite journal</ref> and have been known to rest on their tails to breathe with their heads above water.<ref name="NatGeo"/> They can dive to a maximum depth of Template:Convert; they spend most of their lives no deeper than Template:Convert. 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.<ref name="ADW"/>

Dugongs are semi-nomadic, often traveling long distances in search of food, but staying within a certain range their entire lives.<ref name="ADW"/> 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.<ref name="Sydney"/> Dugong movements mostly occur within a localized area of seagrass beds, and animals in the same region show individualistic patterns of movement. Daily movement 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.<ref name="IUCNpdf"/> One animal was seen as far south as Sydney.<ref name=AussieFauna/> Although they are marine creatures, dugongs have been known to travel up creeks, and in one case a dugong was caught Template:Convert up a creek near Cooktown.<ref name="Sydney"/>

Feeding

A river flowing into the ocean forming a small delta

Typical dugong feeding area in Moreton Bay

Dugongs, along with other sirenians, are referred to as "sea cows" because their diet consists mainly of seagrass, particularly the genera Halophila and Halodule.<ref name="ADW"/> When eating they ingest the whole plant, including the roots,<ref name="Sydney"/> although when this is impossible they will feed on just the leaves.<ref name="IUCNpdf"/> A wide variety of seagrass has been found in dugong stomach contents, and evidence exists they will eat algae when seagrass is scarce.<ref name=AussieFauna/> Although almost completely herbivorous,<ref name="ADW"/> they will occasionally eat invertebrates, such as jellyfish, sea squirts, and shellfish.<ref name="Sydney"/> Dugongs in Moreton Bay, Australia, are omnivorous, feeding on invertebrates such as polychaetes<ref>Berta, Annalisa; Sumich, James L.; Kovacs, Kit M. (2005) Marine Mammals: Evolutionary Biology, Amesterdam: Elsevier. Template:ISBN</ref> or marine algae when 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.<ref name="IUCNpdf"/>

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 the value of a seagrass bed.<ref name="Sydney"/> 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.<ref name="IUCNpdf"/> In the Great Barrier Reef, dugongs feed on low-fiber high-nitrogen seagrass such as Halophila and Halodule,<ref name="Sydney"/> to maximize nutrient intake instead of bulk eating. Seagrasses of a lower seral are preferred, where 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 Template:Convert, and dugongs have been seen feeding as deep as Template:Convert.<ref name="IUCNpdf"/> Dugongs are relatively slow-moving, swimming at around Template:Convert.<ref name=edge>Template:Cite web</ref> When moving along the seabed to feed they walk on their pectoral fins.<ref name=animaldiversity/>

Dugong feeding may favor the subsequent growth of low-fibre, high-nitrogen seagrasses such as Halophilia and Halodule.<ref name="Preen-1995">Template:Cite journal</ref> Species such as Zosteria capricorni are more dominant in established seagrass beds,<ref name="Heinsohn-1976">Template:Cite journal</ref> but grow slowly, while Halophilia and Halodule grow quickly in the open space left by dugong feeding.<ref name="Preen-1995"/> This behavior is known as cultivation grazing and favors the rapidly growing, higher nutrient seagrasses that dugongs prefer.<ref name="Preen-1995"/> Dugongs may also prefer to feed on younger, less fibrous strands of seagrasses,<ref name="Heinsohn-1976"/> 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.<ref name="ADW"/> They will dig up an entire plant and then shake it to remove the sand before eating it. They have been known to collect a pile of plants in one area before eating them.<ref name="animaldiversity"/> The flexible and muscular upper lip is used to dig out the plants. This leaves furrows in the sand in their path.<ref name="ADW"/>

Reproduction and parental care

A dugong mother with a calf half its size traveling just above the seabed

Dugong mother and offspring from East Timor

A dugong reaches sexual maturity between the ages of eight and eighteen, older than in most other mammals.<ref name=EoM>Template:Cite book</ref> Females know that a male has reached sexual maturity by the eruption of the male's tusks, since tusks erupt in males when testosterone levels reach a high enough level.<ref>Template:Cite journal</ref> 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.<ref name="IUCNpdf"/> There is evidence that male dugongs lose fertility at older ages.<ref name=AussieFauna/>

Despite the longevity of the dugong, which may live for 50 years or more, females give birth only a few times during their lives and invest considerable parental care in their young.<ref name=EoM/> The time between births is unclear, with estimates ranging from 2.4 to 7 years.<ref name="IUCNpdf"/>

Mating behaviour varies between populations located in different areas.<ref name="ADW"/> In some populations, males establish a territory that females in estrus then visit.<ref name="IUCNpdf"/> In these areas, the male attempts to impress females while defending the area from other males, a practice known as lekking.<ref name="ADW"/> In other areas many males attempt to mate with the same female,<ref name="IUCNpdf"/> sometimes inflicting injuries on the female or each other.<ref name="Sydney"/> During this event the female copulates with multiple males, who fight to mount her from below. This greatly increases the chances of conception.<ref name="ADW"/>

Females give birth after a 13- to 15-month gestation, usually to just one calf.<ref name=EoM/> Birth occurs in very shallow water, with occasions known where the mothers were almost on the shore.<ref name=AussieFauna/> As soon as the young is born the mother pushes it to the surface to take a breath.<ref name="NatGeo"/> Newborns are already Template:Convert long and weigh around Template:Convert.<ref name="Sydney"/> Once born, calves stay close to their mothers, possibly to make swimming easier.<ref name=AussieFauna/> The calf nurses for 14–18 months, although it begins to eat seagrasses soon after birth.<ref name="IUCNpdf"/> A calf leaves its mother only after it has matured.<ref name="ADW"/>

Importance to humans

Dugongs have historically provided easy targets for hunters, who killed them for their meat, oil, skin, and bones. As the anthropologist A. Asbjørn Jøn has noted, they are often considered the inspiration for mermaids,<ref name="NatGeo"/><ref>Template:Cite journal</ref> and people around the world developed cultures around dugong hunting. In some areas, it remains an animal of great significance,<ref name=AussieFauna/> and a growing ecotourism industry around dugongs has had an economic benefit in some countries.<ref name="ADW"/>

Cave painting that has a shape resembling a dugong

A cave painting of a dugong – Tambun Cave, Perak, Malaysia

There is a 5,000-year-old wall painting of a dugong, apparently drawn by Neolithic peoples, in Tambun Cave, Ipoh, Malaysia. This was discovered by Lieutenant R.L. Rawlings in 1959 while on a routine patrol.<ref>Template:Cite book</ref>

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".<ref name="Blust"/> In Malay, they are sometimes referred to as Template:Lang ("woman of the sea") or Template:Lang ("mermaid princess"), leading to the misconception that the word "dugong" itself means "lady of the sea".<ref name="Marsh"/><ref name="Blust"/><ref name="Medrano">Template:Cite web</ref> 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 the Lesser Sunda Islands (Indonesia). Dugongs are predominantly not traditionally hunted for food in these regions and they remained plentiful until around the 1970s.<ref name="Marsh"/><ref name="UNEP">Template:Cite book</ref>

Conversely, dugong "tears" are considered aphrodisiacs in other parts of Indonesia, Singapore, Malaysia, Brunei, Thailand, Vietnam, and Cambodia.<ref name="Rajamani">Template:Cite journal</ref> 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.<ref name="Marsh">Template:Cite book</ref>

In Palau, dugongs were traditionally hunted with heavy spears from canoes. Although it 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.<ref name="Marsh"/> Dugong meat and oil have traditionally been some of the most valuable foods of Australian Aboriginals and Torres Strait Islanders. Some Aboriginals regard dugongs as part of their Aboriginality.<ref name="Sydney"/>

Local fishermen in Southern China traditionally revered dugongs and regarded them as "miraculous fish". They believed it was bad luck to catch them and they were plentiful in the region before the 1960s. Beginning in the 1950s, a wave of immigrants from other regions that do not hold these beliefs resulted in dugongs being hunted for food and traditional Chinese medicine. This led to a steep decline in dugong populations in the Gulf of Tonkin and the sea around Hainan Island.<ref name="Marsh"/> In Japan, dugongs have been traditionally hunted in the Ryukyu Islands since prehistoric times. Carved ribs of dugongs in the shape of butterflies (a psychopomp) are found throughout Okinawa. They were commonly hunted throughout Japan up until around the 1970s.<ref name="Marsh"/>

Dugongs have also played a role in legends in Kenya, and the animal is known there as the "Queen of the Sea". Body parts are used as food, medicine, and decorations. In the Gulf states, dugongs served not only as a source of food but their tusks were used as sword handles. Dugong oil is important as a preservative and conditioner for wooden boats to people around the Gulf of Kutch in India, who also believe the meat to be an aphrodisiac.<ref name="IUCNpdf"/>

Dugongs have a key role in indigenous marine governance and cultural identity across northern Australia. They are considered part of “sea-country”, a living network of relationships linking people, animals and coastal environments, and contemporary management programs in the Torres Strait and northern Queensland increasingly integrate traditional ecological knowledge with scientific monitoring and co-management arrangements.<ref>Template:Cite journal</ref><ref>Template:Cite book</ref>

Conservation

File:Stamp of Indonesia - 2005 - Colnect 385149 - Dugong Dugong dugon.jpeg

Dugong on a 2005 Indonesian stamp

Dugong numbers have decreased in recent times. For a population to remain stable, the mortality of adults cannot exceed 5% annually. The estimated percentage of females humans can kill without depleting the population is 1–2%.<ref name="Sydney"/> This number is reduced in areas where calving is minimal due to food shortages. Even in the best conditions, a population is unlikely to increase more than 5% a year, leaving dugongs vulnerable to over-exploitation. The fact that they live in shallow waters puts them under great pressure from human activity. Research on dugongs and the effects of human activity on them has been limited, mostly taking place in Australia. In many countries, dugong numbers have never been surveyed. As such, trends are uncertain, with more data needed for comprehensive management.<ref name="IUCNpdf"/> The only data stretching back far enough to mention population trends comes from the urban coast of Queensland, Australia. The last major worldwide study, made in 2002, concluded that the dugong was declining and possibly extinct in a third of its range, with unknown status in another half.<ref name="iucn"/>

The IUCN Red List lists the dugong as vulnerable, and the Convention on International Trade in Endangered Species of Wild Fauna and Flora regulates and in some areas has banned international trade.<ref name=AussieFauna/> Most dugong habitats fall within proposed important marine mammal areas.<ref name="GOBI2020"/> Regional cooperation is important due to the widespread distribution of the animal, and in 1998 there was strong support for Southeast Asian cooperation to protect dugongs. Kenya has passed legislation banning the hunting of dugongs and restricting trawling, but the dugong is not yet listed under Kenya's Wildlife Act as an endangered species. Mozambique has had legislation to protect dugongs since 1955, but this has not been effectively enforced.<ref name="IUCNpdf"/> France has a National Action Plan covering the species, implemented within the Mayotte Marine Natural Park.<ref name="Cremades"/>

Many marine parks have been established on the African coast of the Red Sea, and the Egyptian Gulf of Aqaba is fully protected. The United Arab Emirates has banned all hunting of dugongs within its waters, as has Bahrain. The UAE has additionally banned drift net fishing,<ref name="IUCNpdf"/> and has declared an intention to restore coastal ecosystems dugongs rely on.<ref>Template:Cite web</ref> India and Sri Lanka ban the hunting and selling of dugongs and their products. Japan has listed dugongs as endangered and has banned intentional killing and harassment. Hunting, catching, and harassment are banned by the People's Republic of China. The first marine mammal to be protected in the Philippines was the dugong, although monitoring this is difficult. Palau has legislated to protect dugongs, although this is not well enforced and poaching persists.<ref name="IUCNpdf"/> Indonesia listed dugongs as a protected species in 1999, and in 2018 the Fisheries Ministry began implementing a conservation plan.<ref name="IUCNpdf"/><ref name="Hidayat2024">Template:Cite news</ref> Protection is not always enforced and souvenir products made from dugong parts can be openly found in markets in Bali.<ref>Template:Cite journal</ref> Traditional dugong hunters continued to hunt for many years, and some have struggled to find alternative incomes after ceasing.<ref name="Hidayat2024"/> The dugong is a national animal of Papua New Guinea, which bans all except traditional hunting. Vanuatu and New Caledonia ban the hunting of dugongs. Dugongs are protected throughout Australia, although the rules vary by state; in some areas, indigenous hunting is allowed.<ref name="IUCNpdf"/>

Dugongs are listed under the Nature Conservation Act in the Australian state of Queensland as vulnerable. Most currently live in established marine parks, where boats must travel at a restricted speed and mesh net fishing is restricted.<ref name="Sydney"/> The World Wide Fund for Nature has purchased gillnet licences in northern Queensland to reduce the impact of fishing.<ref>Template:Cite news</ref> In Vietnam, an illegal network targeting dugongs had been detected and was shut down in 2012.<ref name="ThanhNien"/> Potential hunts along Tanzanian coasts by fishermen have raised concerns as well.<ref name="Wiomsa"/>

Human activity

Despite being legally protected in many countries, the main causes of population decline remain anthropogenic and include hunting, habitat degradation, and fishing-related fatalities.<ref name=Audubon/> Entanglement in fishing nets has caused many deaths, although there are no precise statistics. Most issues with industrial fishing occur in deeper waters where dugong populations are low, with local fishing being the main risk in shallower waters.<ref name="IUCNpdf"/> As dugongs cannot stay underwater for a very long period, they are highly prone to death due to entanglement.<ref name="CaseStudy"/> The use of shark nets has historically caused large numbers of deaths, and they have been eliminated in most areas and replaced with baited hooks.<ref name="Sydney"/> Hunting has historically been a problem too, although in most areas they are no longer hunted, except in certain indigenous communities. In areas such as northern Australia, hunting has the greatest impact on the dugong population.<ref name="IUCNpdf"/>

Vessel strikes have proved a problem for manatees, but the relevance of this to dugongs is unknown.<ref name="IUCNpdf"/> Increasing boat traffic has increased danger,<ref name="Sydney"/> especially in shallow waters. Ecotourism has increased in some countries, although the effects remain undocumented. It has been seen to cause issues in areas such as Hainan due to environmental degradation.<ref name="IUCNpdf"/> Modern farming practices and increased land clearing have also had an impact, and much of the coastline of dugong habitats is undergoing industrialization, with increasing human populations.<ref name="Sydney"/> Dugongs accumulate heavy metal ions in their tissues throughout their lives, more so than other marine mammals. The effects are unknown.Template:Citation needed

While international cooperation to form a conservative unit has been undertaken,<ref>Wasmi A. N. 2017. Twenty-three countries unite in Abu Dhabi to conserve the dugong Template:Webarchive. The National (Abu Dhabi). Retrieved on April 19, 2017</ref> socio-political needs are an impediment to dugong conservation in many developing countries. The shallow waters are often used as a source of food and income, problems exacerbated by aid used to improve fishing. In many countries, legislation does not exist to protect dugongs, and if it does it is not enforced.<ref name="IUCNpdf"/>

Oil spills are a danger to dugongs in some areas, as is land reclamation. In Okinawa, the small dugong population is threatened by United States military activity. Plans exist to build a military base close to the Henoko reef, and military activity also adds the threats of noise pollution, chemical pollution, soil erosion, and exposure to depleted uranium.<ref name="IUCNpdf"/> The military base plans have been fought in US courts by some Okinawans, whose concerns include the impact on the local environment and dugong habitats.<ref name="Okinawa"/><ref>King T.. (25 November 2014). "Pity the Dugongs: U.S. DOD Says Court Has No Jurisdiction" Template:Webarchive on The Huffington Post. Retrieved on 5 January. 2015</ref> It was later revealed that the government of Japan was hiding evidence of the negative effects of ship lanes and human activities on dugongs observed during surveys carried out off Henoko reef.<ref>Associated Press. (21 December 2013). 辺野古、船がジュゴンに悪影響　防衛省、観察記録示さず. Japan News Network. Retrieved on 3 January 2015 Template:Webarchive</ref> One of the three individuals has not been observed since June 2015, corresponding to the start of the excavation operations.<ref>Template:Cite web</ref>

Environmental degradation

If dugongs do not get enough to eat they may calve later and produce fewer young.<ref name="Sydney"/> Food shortages can be caused by many factors, such as a loss of habitat, death and decline in the quality of seagrass, and a disturbance of feeding caused by human activity. Sewage, detergents, heavy metals, hypersaline water, herbicides, and other waste products all negatively affect seagrass meadows. Human activity such as mining, trawling, dredging, land reclamation, and boat propeller scarring also cause an increase in sedimentation which smothers seagrass and prevents light from reaching it. This is the most significant negative factor affecting seagrass.<ref name="IUCNpdf"/>

Halophila ovalis—one of the dugong's preferred species of seagrass—declines rapidly due to lack of light, dying completely after 30 days. Extreme weather such as cyclones and floods can destroy hundreds of square kilometres of seagrass meadows, as well as wash dugongs ashore. The recovery of seagrass meadows and the spread of seagrass into new areas, or areas where it has been destroyed, can take over a decade. Most measures for protection involve restricting activities such as trawling in areas containing seagrass meadows, with little to no action on pollutants originating from land. In some areas, water salinity is increased due to wastewater, and it is unknown how much salinity seagrass can withstand.<ref name="IUCNpdf"/>

Dugong habitat in the Oura Bay area of Henoko, Okinawa, Japan, is currently under threat from land reclamation conducted by the Japanese Government in order to build a US Marine base in the area.<ref>Template:Cite web</ref> In August 2014, preliminary drilling surveys were conducted around the seagrass beds there.<ref>The Asahi Shimbun Company (18 August 2014). "Protesters kept at bay as Okinawan seabed survey for relocating U.S. air station gets under way". 朝日新聞デジタル. Template:Webarchive</ref> The construction is expected to seriously damage the dugong population's habitat, possibly leading to local extinction.<ref>Template:Citation</ref>

Capture and captivity

The Australian state of Queensland has sixteen dugong protection parks, and some preservation zones have been established where even Aboriginal Peoples are not allowed to hunt.<ref name="Sydney"/> Capturing animals for research has caused only one or two deaths;<ref name="IUCNpdf"/> dugongs are expensive to keep in captivity due to the long time mothers and calves spend together, and the inability to grow the seagrass that dugongs eat in an aquarium.<ref name="Sydney"/> Only one orphaned calf has ever been successfully kept in captivity.<ref name="ADW"/>

Template:As of only three dugongs are held in captivity worldwide. A female from the Philippines lives at Toba Aquarium in Toba, Mie, Japan.<ref name="IUCNpdf"/> A male also lived there until he died on 10 February 2011.<ref>Template:Cite web</ref> The second resides in Sea World Indonesia,<ref>Template:Cite web</ref> after having been rescued from a fisherman's net and treated.<ref>Template:Cite news</ref> The last one, a male, is kept at Sydney Aquarium, where he has resided since he was a juvenile.<ref>Template:Cite web</ref> Sydney Aquarium had a second dugong for many years, until she died in 2018.<ref>In Memory of Wuru Template:Webarchive, Sydney Aquarium</ref>

Gracie, a captive dugong at Underwater World, Singapore, was reported to have died in 2014 at the age of 19, from complications arising from an acute digestive disorder.<ref>Template:Cite web</ref>

External links

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