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DugongDugong dugon

Every figure, record and mechanism on the Dugong profile was written from a source, and this is the working table behind it: 52 claims checked word for word against these sources. The left column is what the page says. The right column is the source's own words, copied, not paraphrased; a ... marks a cut and[brackets] an insertion. Open any source and check it yourself.

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Source
01

AnAge: The Animal Ageing and Longevity Database

Dugong (Dugong dugon) longevity, ageing, and life history. AnAge: The Animal Ageing and Longevity Database.

The page saysmay live more than 50 years
The source saysIt is estimated that these animals live more than 50 years in the wildNote: tagline
The page saysDugongs are estimated to live more than 50 years in the wild, and one estimate suggests they may reach 73.
The source saysIt is estimated that these animals live more than 50 years in the wild, with one estimate suggesting that they may live up to 73 years
The page saysgrazes seagrass for an estimated 50 years or more
The source saysIt is estimated that these animals live more than 50 years in the wild, with one estimate suggesting that they may live up to 73 yearsNote: vibe.reason; same quote as the body claim "Dugongs are estimated to live more than 50 years in the wild"

Source
02

Macdonald

Macdonald. Dugong dugon (dugong). Animal Diversity Web, University of Michigan.

The page saysrips up seagrass with a flexible upper lip
The source saysDugongs use their flexible upper lip to rip up entire seagrass plants.Note: tagline
The page saysA sea cow
The source saysDugongs ( Dugong dugon ), also known as sea cows
The page saysTropical coastal waters, generally shallow, from East Africa to Vanuatu
The source saysencompassing tropical waters from East Africa to VanuatuNote: stats.habitat
The page saysgenerally shallow
The source saysDugongs generally inhabit shallow watersNote: stats.habitat
The page saysSeagrass, and marine algae when seagrass is scarce
The source saysWhen seagrass is scarce, dugongs also eat marine algae.Note: stats.diet
The page saysSeagrass, and marine algae when seagrass is scarce
The source saysThey consume seagrass, particularly of the families Potamogetonaceae and HydrocharitaceaeNote: stats.diet
The page saysRips up whole seagrass plants with a flexible upper lip
The source saysDugongs use their flexible upper lip to rip up entire seagrass plants.Note: stats.superpower
The page saysDugongs are plant-eating grazers.
The source saysDugongs are primary consumers
The page saysSeagrass is their main food
The source saysSeagrass beds consisting of phanerogamous seagrasses, their primary source of nourishment
The page saysthey harvest it with a flexible upper lip that rips up entire plants
The source saysDugongs use their flexible upper lip to rip up entire seagrass plants.
The page saysIf a plant will not come up whole, the dugong tears off the leaves.
The source saysIf the entire plant cannot be uprooted, they rip off leaves.
The page saysThe grazing leaves furrows in the seagrass bed that can be seen from the surface.
The source saysTheir grazing leaves distinctive furrows in the seagrass beds that can be detected from the surface.
The page saysSensory bristles cover a dugong's upper lip and help it find food.
The source saysSensory bristles that cover their upper lip assist in locating food.
The page saysBristles also cover the rest of its body.
The source saysBristles also cover the dugong’s body.
The page saysAn adult dugong weighs 230 to 400 kg and is 2.4 to 4 m long.
The source saysAdult dugongs weigh from 230 to 400 kg and can range from 2.4 to 4 m in length.
The page saysA long intestine aids the digestion of seagrass, and the dugong has a low metabolism.
The source saysTheir long intestine aids the digestion of seagrass. They also have a low metabolism.
The page saysA dugong's age is estimated by counting the growth layers in a tusk.
The source sayswhich is estimated by counting the growth layers that make up a dugong’s tusks
The page saysTusks are projections of the incisor teeth, and they are usually only visible through the skin in mature males and old females.
The source saysTusks are present in all dugongs, but they are usually only visible through the skin in mature males, whose tusks are prominent, and in old females. Their tusks are projections of the incisor teeth.
The page saysMating can be violent, and the protruding tusks leave scars on females and on competing males.
The source saysThis can be violent, as witnessed by scars observed on the body of females and on competing males from their protruding tusks.
The page saysDugongs live in tropical waters from East Africa to Vanuatu, about 26 degrees north and south of the equator.
The source saysencompassing tropical waters from East Africa to Vanuatu, about 26 degrees both north and south of the equator
The page saysThe biggest population lives off northern Australia, between Shark Bay and Moreton Bay.
The source saysThe largest population of sea cows is found in the northern waters of Australia between Shark Bay (Western Australia) and Moreton Bay (Queensland).
The page saysThe second biggest lives in the Arabian Gulf.
The source saysThe second largest population is found in the Arabian Gulf.
The page saysThey stay in shallow water, usually about 10 m deep, and occasionally dive as deep as 39 m to feed.
The source saysDugongs generally inhabit shallow waters, remaining at depths of around 10 m, although they occasionally dive to depths of 39 m to feed.
The page saysTheir nostrils sit on top of the head, and valves keep them shut during a dive.
The source saysPaired nostrils, used in ventilation when the dugong surfaces every few minutes, are located on top of the head. Valves keep them shut during dives.
The page saysA dugong surfaces every few minutes to breathe.
The source saysused in ventilation when the dugong surfaces every few minutes
The page saysThey chirp, whistle and bark to communicate.
The source saysdugongs use chirps, whistles, barks and other sounds that echo underwater in order to communicate
The page saysthey use hearing more than sight
The source saysdugongs have developed exceptional hearing, which they use more than their sight
The page saysTheir eyesight is poor
The source saysThe vision of dugongs, however, is quite poor
The page saysSharks, crocodiles and killer whales feed on juveniles.
The source saysSharks , crocodiles , and killer whales , however, feed on juvenile dugongs.
The page sayshunted to extinction
The source saysHydrodamalis gigas (Steller’s sea cow), hunted to extinction
The page says7 to 10 m long
The source sayswith a body length of 7 to 10 m
The page saysNo, though they are cousins. A dugong's tail has a straight or concave edge and works like a propeller, while a manatee's tail is shaped like a paddle.
The source saysa tail with a straight or concave perimeter that is used as a propeller. Their tail differentiates them from manatees, the tail of which is paddle-shaped.
The page saysPregnancy lasts 13 to 14 months, and a female produces one calf every 2.5 to 7 years, depending on where she lives.
The source saysthey only produce one calf every 2.5 to 7 years depending on location. This may be due to the long gestation period, which is between 13 and 14 months.Note: 'may be due to' hedges the cause of the slow rate, not the 13 to 14 month gestation
The page saysThe calf weighs about 30 kg at birth and suckles for 18 months or longer.
The source saysAt birth, calves are about 30 kg in weight, 1.2 m in length, and very vulnerable to predators. Calves nurse for 18 months or longer
The page saysThreats include hunting, fishing nets, boat strikes and habitat loss.
The source saysThe are hunted by some ethnic tribes in Australia and Malaysia, caught in gill and mesh nets set by fishers, struck by boats and ships, and are losing habitat and resources due to anthropogenic activities.Note: 'some' scopes who hunts dugongs, not whether hunting is a threat
The page saysTusks that tell its age
The source sayswhich is estimated by counting the growth layers that make up a dugong’s tusksNote: heading
The page saysThey are quite shy: approached with care, they investigate a diver or boat from long range but hesitate to come closer.
The source saysThey are quite shy, and when approached cautiously, they investigate diver or boat at a long range but hesitate to come any closer.
The page saysShy and shark-wary
The source saysThey are quite shyNote: heading; shark-wary is the Shark Bay tiger shark study below
The page saysA lip that ploughs the seabed
The source saysTheir grazing leaves distinctive furrows in the seagrass bedsNote: heading
The page saysA dugong has a low metabolism
The source saysTheir long intestine aids the digestion of seagrass. They also have a low metabolism.Note: vibe.reason; same quote as the body claim "A long intestine aids the digestion of seagrass, and the dug"

Source
03

Wirsing, Heithaus & Dill 2007

Wirsing, Heithaus & Dill (2007). Fear factor: do dugongs (Dugong dugon) trade food for safety from tiger sharks (Galeocerdo cuvier)? Oecologia.

The page saysIn Shark Bay, dugongs used shallow and deep water in proportion to the food in each when large tiger sharks were scarce.
The source saysForagers used shallow and deep habitats in proportion to food availability (input matching) when large tiger sharks were scarce
The page saysWhen large tiger sharks were common, they overused the deep water, which the study calls safe but impoverished.
The source saysoverused deep habitats when sharks were commonNote: 'safe but impoverished': 'allocating time to safe but impoverished foraging patches'
The page saysThe authors describe an apparent food-safety trade-off.
The source saysThis apparent food-safety trade-off has important implications for seagrass community structure in Shark Bay

Source
04

Springer et al. 2015

Springer et al. (2015). Interordinal gene capture, the phylogenetic position of Steller’s sea cow based on molecular and morphological data, and the macroevolutionary history of Sirenia. Molecular Phylogenetics and Evolution.

The page saysIts family once included Steller's sea cow
The source sayssupport the inclusion of H. gigas in Dugongidae with D. dugon and fossil dugongids
The page saysa North Pacific giant
The source sayswas a large, edentulous North Pacific sirenian
The page saysaround 1768
The source saysThe recently extinct (ca. 1768) Steller's sea cowNote: ADW gives 1767 alongside an internally inconsistent '36 years after their discovery'; the 2015 paper's ca. 1768 is used

Source
05

Marsh & Sobtzick 2019

Marsh & Sobtzick (2019). Dugong dugon. The IUCN Red List of Threatened Species 2019: e.T6909A160756767.

The page saysThe IUCN Red List rates the dugong Vulnerable.
The source saysIUCN Red List category: Vulnerable (VU).
The page saysVulnerable
The source saysIUCN Red List category: Vulnerable (VU).Note: stats.conservationStatus; species-level assessment 2015 via GBIF's copy; GBIF check noted here, not cited
The page saysIt is listed as Vulnerable on the IUCN Red List.
The source saysIUCN Red List category: Vulnerable (VU).

How the table was made: a writer drafted the profile from these sources and logged each claim with its quote, a reviewer with nothing but this table checked every sentence said no more than its quote, and a script confirmed each quote appears word for word in the source. The method is in the site'sAbout page.