Cited by 9Wildlife Ecology and ConservationAnimal Behavior and Welfare StudiesPrimate Behavior and Ecology

Choeropsis liberiensis (Artiodactyla: Hippopotamidae)

Open access
Flacke, Gabriella L, Decher, Jan·2019·Mammalian Species

Abstract

Choeropsis liberiensis (Morton, 1849), commonly called the pygmy hippopotamus or pygmy hippo, is the only extant species in the genus Choeropsis. A solitary, forest-dwelling ungulate endemic to the Upper Guinean forest ecosystem in West Africa, it is classified as “Endangered” by the International Union for Conservation of Nature and Natural Resources and is a Convention on International Trade in Endangered Species of Wild Flora and Fauna (CITES) Appendix II species. The smaller of the two extant hippopotamids, it is relatively uncommon in zoological facilities and private collections worldwide.

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Written from the paper’s full text.

TL;DR

This Mammalian Species account compiles the taxonomy, morphology, physiology, ecology, behavior, genetics, and conservation status of the pygmy hippopotamus (*Choeropsis liberiensis*), the only extant member of its genus and an Endangered Upper Guinean forest endemic. It emphasizes how much of the species' biology rests on captive animals and indirect field evidence, with wild population size and many ecological parameters still unresolved.

Key findings

  • *C. liberiensis* is distinguished from the common hippopotamus by smaller size (wild adult weights recorded at 204 kg for a male and 165 and 170 kg for two females; captive average 160–275 kg, shoulder height 70–80 cm versus >1,500 kg and 130–140 cm in *H. amphibius*), dental formula i 2/1, c 1/1, p 4/4, m 3/3 (total 38), and a distribution restricted to Côte d'Ivoire, Guinea, Liberia, and Sierra Leone.
  • Wild population numbers are unknown; estimates range from 2,000–3,000 worldwide to possibly 15,000 for Côte d'Ivoire alone, with country-level figures such as ≤80 ± 10 for Sierra Leone (White 1986), roughly 150 currently for Sierra Leone, 50–150 for two Guinean reserves, and a modeled ~2,000 females and <600 males in the Gola transboundary landscape (128 of 525 examined 1-km² cells occupied).
  • Reproduction in captivity: estrous cycle 28–40 days (mean 35 days behaviorally; 27–32 days hormonally), gestation 188–210 days (mean ~200), single calf, birth weights 3–8 kg (mean 5.7 kg); a 1919–1975 review of 219 births found 62% calf survival, with most deaths in the first month and higher birth weight positively correlated with survival past 3 months.
  • The captive population at end-2016 comprised 153 males, 229 females, and 9 undetermined-sex animals in 144 institutions, derived from 162 founders; the 2015 population (n = 377) from 60 founders had an average inbreeding coefficient of 0.0600 and gene diversity of 0.9695. Polycystic kidney disease prevalence exceeds 37% in captive animals and may be an X-linked dominant trait.

Methods

  • Species account (Mammalian Species) synthesizing published literature, studbook data, and field reports; no new primary data collection.
  • Sources include field surveys using transect counts of footprints and dung, camera traps, community/hunter questionnaires, radiotelemetry (one female n = 5 and one male home-range study), and zoo-based morphometric, endocrine, anesthetic, and pathology records.
  • Taxonomic treatment follows Boisserie (2005) and Groves and Grubb (2011) in recognizing *Choeropsis* (not *Hexaprotodon*) and two subspecies, *C. l. liberiensis* and *C. l. heslopi*.

Limitations

  • Stated: detailed wild information is scarce because in situ research is difficult; most data come from zoo specimens, all of the nominate subspecies. Morphometric measures including body mass are unavailable for wild animals except two females weighed by Hentschel (1990). Population assessments rely on indirect evidence (interviews, bushmeat surveys, footprint/dung transects, camera traps) and require home range, habitat preference, and social behavior data that are lacking; the widely cited ≤3,000 figure originates from gray literature. The radiotelemetry home-range data are biased by translocation, captivity, habituation, small sample size, and only 3 months of post-release tracking. Hematology and biochemistry reference ranges came from >10 but <50 animals of unknown health status and do not meet ASVCP standards. Studbook-based genetic diversity measures assume equal founder relatedness and may contain pedigree errors.
  • Evident from the text: many anatomical, physiological, and disease findings rest on single animals or very small samples (e.g., one subadult female eye measurements, one anesthetized male, seven ejaculates), and several ecological claims (diet, activity pattern, calving season) derive from secondhand reports or conflicting accounts rather than direct observation.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1093/mspecies/sez017

Cites

103 of 103 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

25 of 266 cited sources checked · 13 supported · 0 flagged · accuracy not yet measured

  • Premisecitation

    Choeropsis liberiensis is the only extant species in the genus Choeropsis.

    “Choeropsis liberiensis (Morton, 1849), commonly called the pygmy hippopotamus or pygmy hippo, is the only extant species in the genus Choeropsis.”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites Boisserie 2005 source
  • Premisecitation

    Retention of intrinsic adductor muscles in the feet functions to prevent splaying of the toes, an adaptation to walking on muddy substrates.

    “Retention of intrinsic adductor muscles in the feet functions to prevent splaying of the toes, an adaptation to walking on muddy substrates (Fisher et al. 2007).”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites Fisher et al. 2007 source
  • Premisecitation

    The rhomboid muscle group can either originate in the neck or from the occipital bone in C. liberiensis.

    “For example, the rhomboid muscle group can either originate in the neck (Campbell 1936;Fisher et al. 2007) or from the occipital bone (Macalister 1873).”
    Quote in the paperNot a substantial claim1 of 3 sources checked
    • cites Campbell 1936 source
    • cites Fisher et al. 2007 source
    • cites Macalister 1873

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Premisecitation

    The earliest remains that unequivocally resemble extant hippos appeared in the fossil record in the late Miocene, around 8 million years ago.

    “The earliest remains that unequivocally resemble extant hippos appeared in the fossil record in the late Miocene, around 8 million years ago (Weston 2000), and later within this period its range also extended into parts of Eurasia (Boisserie 2005).”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites Weston 2000 source
    • cites Boisserie 2005 source
  • Premisecitation

    Later within the late Miocene, the range of hippopotamids extended into parts of Eurasia.

    “The earliest remains that unequivocally resemble extant hippos appeared in the fossil record in the late Miocene, around 8 million years ago (Weston 2000), and later within this period its range also extended into parts of Eurasia (Boisserie 2005).”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites Boisserie 2005 source
  • Classified as probably not a substantial claim. 42
  • May combine two claims. 92
  • The quote only partly states this claim. 1
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Rarely there are three total mandibular incisors instead of the single pair in C. liberiensis.

    “Rarely there are three total mandibular incisors instead of the single pair (Johnston 1906).”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites Johnston 1906 source

      The available copy’s passages on Liberian fauna, including the discussion near p. 89, do not address the number of mandibular incisors in C. liberiensis. Searches for the species, pygmy hippopotamus, and incisors found no relevant passage; the copy is truncated, so the decisive description may be missing. (LLM, conf=0.73)

      Experimental — accuracy not yet measured
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Recent molecular phylogenetic studies and comparative morphological analyses support Hippopotamidae and Cetacea as forming a monophyletic group.

    “Recent molecular phylogenetic studies and comparative morphological analyses have supported Hippopotamidae and Cetacea as forming a monophyletic group (Shimamura et al. 1997;Nomura et al. 1998;Ursing and Arnason 1998;Nomura and Yasue 1999;Geisler and Uhen 2003;Boisserie 2005;Boisserie et al. 2005;Fisher et al. 2007);”
    Quote in the paperNot a substantial claim2 of 3 sources checked
    • cites Shimamura et al. 1997 source
    • cites Boisserie 2005 source
    • cites Fisher et al. 2007 source

      The Abstract says molecular studies indicate that hippos and cetaceans are sister taxa. In “Functional and Phylogenetic Considerations,” the authors say their forelimb comparisons support the molecular data, but they call for further study to determine whether hippos were closely allied to Cetacea. The paper therefore supports the molecular part of the claim, but does not establish that its comparative morphological analysis supports the hippo–cetacean clade. (LLM, conf=0.87)

      Experimental — accuracy not yet measured
  • May combine two claims.

    Premisecitation

    Proportionally, the brain case is larger and the muzzle is shorter in C. liberiensis than in the common hippopotamus.

    “Proportionally, the brain case is larger and the muzzle is shorter in C. liberiensis than in the common hippopotamus (Fig. 2; Johnston 1906).”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites Johnston 1906 source

      The passage near p. 89 discusses Liberian animals but does not compare the skulls of C. liberiensis and the common hippopotamus. Searches for the species name, brain case, muzzle, and skull comparison found no relevant passage in our copy, whose end may be missing. (LLM, conf=0.74)

      Experimental — accuracy not yet measured
  • Classified as probably not a substantial claim. May combine two claims.

    Premisecitation

    Boisserie (2005) concluded that the mix of primitive and derived features of the extant pygmy hippo gives it a distinct lineage, validating the genus Choeropsis for the pygmy hippo and restricting the genus Hexaprotodon to the fossil lineage found mostly in Asia.

    “Most recently, Boisserie (2005) concluded that the mix of primitive and derived features of the extant pygmy hippo gives it a distinct lineage, validating the genus Choeropsis for the pygmy hippo and restricting the genus Hexaprotodon to the fossil lineage found mostly in Asia (Falconer and Cautley 1836).”
    Quote in the paperSubstantial claim1 of 2 sources checked
    • cites Boisserie 2005 source
    • cites Falconer and Cautley 1836

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Interpretationcitation

    Overall, the myology of C. liberiensis resembles ruminants more closely than suids, and both extant hippo species are unique in retaining several primitive features in the forelimb, consistent with the hypothesis that hippopotamids diverged from other Artiodactyla early in the history of this group.

    “Overall, the myology of the C. liberiensis resembles ruminants more closely than suids, and both extant hippo species are unique in retaining several primitive features in the forelimb, consistent with the hypothesis that hippopotamids diverged from other Artiodactyla early in the history of this group (Fisher et al. 2007).”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites Fisher et al. 2007 source
  • May combine two claims.

    Premisecitation

    Other recent confirmed records of C. liberiensis are from Gola National Forest in the west, from the Wonegizi National Forest in the north, on the border with Guinea, and in Sapo National Park in the southeast.

    “Other recent confirmed records are from Gola National Forest in the west, from the Wonegizi National Forest in the north, on the border with Guinea, and in Sapo National Park in the southeast (Collen et al. 2011).”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites Collen et al. 2011 source

      The Abstract reports seven camera-trap photographs confirming C. liberiensis in Sapo National Park, Liberia. Our copy does not report confirmed records from Gola National Forest or Wonegizi National Forest, so the citation supports only the Sapo portion of the sentence. (LLM, conf=0.88)

      Experimental — accuracy not yet measured
  • May combine two claims.

    Premisecitation

    The insertion site of the brachialis muscle can be on the radius only or on both the radius and ulna in C. liberiensis.

    “The insertion site of the brachialis muscle can be on the radius only (Macalister 1873;Fisher et al. 2007) or on both the radius and ulna (Campbell 1936); the radius and ulna are functionally or actually fused in artiodactyls.”
    Quote in the paperNot a substantial claim1 of 3 sources checked
    • cites Macalister 1873

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Fisher et al. 2007 source
    • cites Campbell 1936 source
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Hippopotamids are believed to have originated in Africa sometime in the mid-Miocene period, approximately 11-16 million years ago, in the areas of modern-day Kenya and Tunisia.

    “Hippopotamids are believed to have originated in Africa sometime in the mid-Miocene period, approximately 11-16 million years ago, in the areas of modern-day Kenya and Tunisia (Pickford 1983;Boisserie 2005).”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites Pickford 1983 source
    • cites Boisserie 2005 source

      The Introduction says Hippopotamidae most probably had their roots in Africa during the middle Miocene. It mentions a Miocene hippopotamid from Kenya, but does not identify Kenya or Tunisia as places of origin or give the specific 11–16-million-year range. (LLM, conf=0.87)

      Experimental — accuracy not yet measured
  • May combine two claims.

    Premisecitation

    C. liberiensis has retained several features more adapted to a terrestrial lifestyle compared to the common hippopotamus, including proportionally longer limbs and only moderately webbed toes that spread more widely under its own weight.

    “Choeropsis liberiensis has retained several features more adapted to a terrestrial lifestyle compared to the common hippopotamus, including proportionally longer limbs and only moderately webbed toes that spread more widely under its own weight (Johnston 1906 ;Pocock 1923;Fisher et al. 2007).”
    Quote in the paperNot a substantial claim2 of 3 sources checked
    • cites Johnston 1906 source

      The available copy’s passages on Liberian fauna (Chapter II) do not describe Choeropsis liberiensis or compare its limbs and toes with those of the common hippopotamus. Searches for hippopotamus, webbed toes, and the claimed limb proportions found no relevant passage; the copy is truncated, so the relevant discussion may be missing. (LLM, conf=0.72)

      Experimental — accuracy not yet measured
    • cites Pocock 1923 source
    • cites Fisher et al. 2007 source

      The Functional and Phylogenetic Considerations section says hippos retain terrestrial locomotor patterns and have tendons that control toe splay on soft ground. It does not establish that pygmy hippos have proportionally longer limbs, moderately webbed toes, or greater terrestrial adaptation than common hippos; the Abstract says common hippos share the described toe-control features. (LLM, conf=0.85)

      Experimental — accuracy not yet measured
  • May combine two claims.

    Premisecitation

    The trapezius muscle can variably originate from the last two cervical vertebrae or the occipital bone in C. liberiensis, whereas the common hippopotamus lacks an occipital origin.

    “Similarly, the trapezius muscle can variably originate from the last two cervical vertebrae (Campbell 1936) or the occipital bone (Macalister 1873;Fisher et al. 2007) in C. liberiensis, whereas the common hippopotamus lacks an occipital origin.”
    Quote in the paperNot a substantial claim1 of 3 sources checked
    • cites Campbell 1936 source
    • cites Macalister 1873

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Fisher et al. 2007 source
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    The Cetacea and the Hippopotamidae are believed to share a common ancestry, with initial divergence estimated around 54 million years ago.

    “The Cetacea and the Hippopotamidae are believed to share a common ancestry, with initial divergence estimated around 54 million years ago (Ursing and Arnason 1998).”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites Ursing and Arnason 1998 source
  • May combine two claims.

    Premisecitation

    The current estimate for Sierra Leone is roughly 150 C. liberiensis individuals countrywide, primarily within the Gola Forest complex.

    “Data from recent field surveys were not sufficient to determine actual abundance (Conway 2013); the current estimate for Sierra Leone is roughly 150 individuals countrywide, primarily within the Gola Forest complex, including the Moa River islands (Lindsell et al. 2011;Mallon et al. 2011).”
    Quote in the paperNot a substantial claim1 of 3 sources checked
    • cites Conway 2013

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Lindsell et al. 2011 source

      The Results (page not provided) document pygmy hippopotamuses in the Gola area and on Tiwai Island in the Moa River. The Discussion (page not provided) suggests several tens of animals in and around the reserves, but does not give a countrywide estimate of roughly 150 or establish that most of Sierra Leone’s population is there. (LLM, conf=0.88)

      Experimental — accuracy not yet measured
    • cites Mallon et al. 2011

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    Population surveys conducted in Liberia have indicated a minimum of 1,000 C. liberiensis and perhaps several thousand.

    “Population surveys conducted in Liberia have indicated a minimum of 1,000 (Verschuren 1982) and perhaps several thousand (Eltringham 1993).”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites Verschuren 1982 source
    • cites Eltringham 1993

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    Further threats to C. liberiensis include lack of adequate financial and legal protection for the few remaining intact areas of habitat, poaching for bushmeat, and increasing human settlement adjacent to protected areas.

    “Further threats include lack of adequate financial and legal protection for the few remaining intact areas of habitat, poaching for bushmeat, and increasing human settlement adjacent to protected areas (Anstey 1991b;Critical Ecosystem Partnership Fund 2015;Lindsell et al. 2011;Ransom et al. 2015).”
    Quote in the paperNot a substantial claim1 of 3 sources checked
    • cites Anstey 1991b

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Critical Ecosystem Partnership Fund 2015

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Lindsell et al. 2011 source

      The Discussion (page unavailable) says that 63% of riverine forest in the Gola area lies outside the reserves, so pygmy hippopotamuses may not be well protected. It also identifies an increasing human population and demand for bushmeat as threats to the forest. It does not establish inadequate financial or legal protection, or identify poaching and settlement adjacent to protected areas as specific threats to C. liberiensis. (LLM, conf=0.84)

      Experimental — accuracy not yet measured
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data

    The greatest length of the skull of an adult female Choeropsis liberiensis specimen (ZFMK MAM 1965.0570) from Côte d'Ivoire is 339 mm.

    “Greatest length of skull is 339 mm.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationcitation

    The animals at the higher end of the weight range are undoubtedly overweight.

    “The animals at the higher end of the weight range are undoubtedly overweight (Flacke et al. 2015).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Flacke et al. 2015 source
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    The view validating Choeropsis was also recently embraced by Groves and Grubb (2011).

    “This view was also recently embraced by Groves and Grubb (2011).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Groves and Grubb 2011

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    Average weight in captivity for C. liberiensis ranges from 160 to 275 kg with a shoulder height of 70-80 cm.

    “Average weight in captivity ranges from 160 to 275 kg with a shoulder height of 70-80 cm (Lang 1975);”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Lang 1975

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisenone given

    The common hippopotamus frequents riverine savannahs.

    “C. liberiensis inhabits primary and secondary rainforest and swamps (Bülow 1987;Hentschel 1990), whereas the common hippopotamus frequents riverine savannahs.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Premisereasoning

    C. liberiensis is distinguished from the common hippopotamus Hippopotamus amphibius by its smaller size, dental formula, distribution, and habitat.

    “Choeropsis liberiensis (Fig. 1) is distinguished from the common hippopotamus Hippopotamus amphibius by its smaller size, dental formula, distribution, and habitat.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisenone given

    C. liberiensis is the smaller of the two extant hippopotamids.

    “The smaller of the two extant hippopotamids, it is relatively uncommon in zoological facilities and private collections worldwide.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    The common hippopotamus is found throughout sub-Saharan Africa.

    “the common hippopotamus is found throughout sub-Saharan Africa (Boisserie et al. 2005).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Boisserie et al. 2005 source
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisenone given

    C. liberiensis is gray to black in color with occasional depigmented pink patches on the body and limbs.

    “Choeropsis liberiensis is gray to black in color with occasional depigmented pink patches on the body and limbs (Fig. 1).”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Coarse, bristle-like hairs are found only at the ear margins, on the lips, and at the end of the tail in C. liberiensis.

    “Coarse, bristle-like hairs are found only at the ear margins, on the lips, and at the end of the tail (Lochte 1951).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Lochte 1951

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    A wild common hippopotamus can weigh upwards of 1,500 kg with a shoulder height of 130-140 cm.

    “by comparison, a wild common hippopotamus can weigh upwards of 1,500 kg with a shoulder height of 130-140 cm (Marshall and Sayer 1976).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Marshall and Sayer 1976 source
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisenone given

    C. liberiensis is a CITES Appendix II species.

    “A solitary, forest-dwelling ungulate endemic to the Upper Guinean forest ecosystem in West Africa, it is classified as “Endangered” by the International Union for Conservation of Nature and Natural Resources and is a Convention on International Trade in Endangered Species of Wild Flora and Fauna (CITES) Appendix II species.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Premisecitation

    C. liberiensis is limited in geographic distribution to the Upper Guinean forest ecosystem of West Africa and is now found only in Côte d'Ivoire, Guinea, Liberia, and Sierra Leone.

    “C. liberiensis is limited in geographic distribution to the Upper Guinean forest ecosystem of West Africa and is now found only in Côte d'Ivoire, Guinea, Liberia, and Sierra Leone (Ransom et al. 2015);”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Ransom et al. 2015

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Premisenone given

    C. liberiensis is relatively uncommon in zoological facilities and private collections worldwide.

    “The smaller of the two extant hippopotamids, it is relatively uncommon in zoological facilities and private collections worldwide.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisenone given

    C. liberiensis is classified as Endangered by the International Union for Conservation of Nature and Natural Resources.

    “A solitary, forest-dwelling ungulate endemic to the Upper Guinean forest ecosystem in West Africa, it is classified as “Endangered” by the International Union for Conservation of Nature and Natural Resources and is a Convention on International Trade in Endangered Species of Wild Flora and Fauna (CITES) Appendix II species.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Premisecitation

    The International Studbook reports a body mass range of 180-260 kg and a shoulder height of 80 cm for C. liberiensis.

    “The International Studbook reports a body mass range of 180-260 kg and a shoulder height of 80 cm (Steck 2017);”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Steck 2017

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisenone given

    C. liberiensis is a solitary, forest-dwelling ungulate endemic to the Upper Guinean forest ecosystem in West Africa.

    “A solitary, forest-dwelling ungulate endemic to the Upper Guinean forest ecosystem in West Africa, it is classified as “Endangered” by the International Union for Conservation of Nature and Natural Resources and is a Convention on International Trade in Endangered Species of Wild Flora and Fauna (CITES) Appendix II species.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Subdermal glands of C. liberiensis secrete an oily clear-to-white, foamy fluid that protects the skin against sunburn, dehydration, and bacterial infection.

    “Subdermal glands secrete an oily clear-to-white, foamy fluid that protects the skin against sunburn, dehydration, and bacterial infection (Eulenberger 1995;Hashimoto et al. 2007).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Eulenberger 1995

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Hashimoto et al. 2007 source
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    The skin of C. liberiensis is thick with a rubbery texture.

    “The skin is thick with a rubbery texture (Flach et al. 1998).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Flach et al. 1998 source
  • May combine two claims.

    Premisecitation

    Body mass for adult female C. liberiensis (n = 5) ranged from 179 to 267 kg; for adult males (n = 2) 208 kg and 273 kg.

    “Body mass for adult females (n = 5) ranged from 179 to 267 kg; for adult males (n = 2) 208 kg and 273 kg (Lang 1975).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Lang 1975

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisenone given

    There is a dearth of detailed information concerning Choeropsis in the wild due to the limitations for in situ research; the majority of data is derived from zoo specimens, all of which are of the nominate species C. liberiensis.

    “There is a dearth of detailed information concerning Choeropsis in the wild due to the limitations for in situ research; the majority of data is derived from zoo specimens, all of which are of the nominate species C. liberiensis.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Premisecitation

    The extant Choeropsis liberiensis is endemic only to the Upper Guinean forest ecosystem in West Africa, and its distribution is limited to fragmented populations in Côte d'Ivoire, Guinea, Liberia, and Sierra Leone.

    “The extant Choeropsis liberiensis is endemic only to the Upper Guinean forest ecosystem in West Africa (Fig. 3), and its distribution is limited to fragmented populations in Côte d'Ivoire, Guinea, Liberia, and Sierra Leone (Ransom et al. 2015).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Ransom et al. 2015

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Cetartiodactyla was proposed as the taxon name for the group formed by Hippopotamidae and Cetacea.

    “Cetartiodactyla was proposed as the taxon name for the group (Montgelard et al. 1997) and subsequently more clearly defined (O' Leary and Gatesy 2008).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Montgelard et al. 1997 source
    • cites O' Leary and Gatesy 2008 source
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    The ears and nostrils of C. liberiensis function as valves that close tightly when the animal is under water.

    “The ears and nostrils function as valves that close tightly when the animal is under water (Pocock 1923).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Pocock 1923 source
  • May combine two claims.

    Premisecitation

    The four stomach compartments of C. liberiensis are similar to those of a ruminant and include the nonglandular visceral and parietal blind sacs (also termed left and right diverticula), the vestibulum, the connecting chamber, and the customary glandular stomach.

    “The four stomach compartments are similar to those of a ruminant and include the nonglandular visceral and parietal blind sacs (also termed left and right diverticula), the vestibulum, the connecting chamber, and the customary glandular stomach (Langer 1975;Macdonald and Hartman 1983).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Langer 1975 source
    • cites Macdonald and Hartman 1983 source
  • May combine two claims.

    Premisecitation

    The highly vascularized and inelastic skin of C. liberiensis is about 1 cm thick with extensive subcutaneous fat and a rubbery texture.

    “The highly vascularized and inelastic skin of C. liberiensis is about 1 cm thick with extensive subcutaneous fat and a rubbery texture (Flach et al. 1998).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Flach et al. 1998 source
  • May combine two claims.

    Premisecitation

    The volume of the combined fore stomachs in the newborn C. liberiensis is about 68% of the total gastric volume; in adults this proportion increases to 94%.

    “The volume of the combined fore stomachs in the newborn C. liberiensis is about 68% of the total gastric volume; in adults this proportion increases to 94% (Langer 1975).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Langer 1975 source
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    The vertebral formula of C. liberiensis is 7C, 14T, 5L, 4S, and 10 or more CA, total 40 or more.

    “The vertebral formula of C. liberiensis is 7C, 14T, 5L, 4S, and 10 or more CA, total 40 or more (Macalister 1873).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Macalister 1873

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    Skin secretions from a female C. liberiensis had a pH of 9.5 and lower mean sodium (Na+) and potassium (K+) concentrations than secretions from the common hippopotamus, possibly reflecting dietary or metabolic differences.

    “Skin secretions from a female C. liberiensis had a pH of 9.5 and lower mean sodium (Na + ) and potassium (K + ) concentrations than secretions from the common hippopotamus, possibly reflecting dietary or metabolic differences (Olivier 1975).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Olivier 1975 source
  • May combine two claims.

    Premisecitation

    Confirmed reports of C. liberiensis presence are from both Tiwai Island and other small islands along the Moa River, and from the Gola Forest Reserve Complex along the Mano River on the border with Liberia.

    “Confirmed reports of its presence are from both Tiwai Island and other small islands along the Moa River (White et al. 1986;Conway 2013), and from the Gola Forest Reserve Complex along the Mano River on the border with Liberia (Hillers and Muana 2010;Lindsell et al. 2011;Mallon et al. 2011).”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites White et al. 1986

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Conway 2013

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Mallon et al. 2011

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    The connecting chamber is oriented in a dorsal-to-ventral direction in the newborn to assist with passage of milk into the glandular stomach; the orientation changes in the adult to promote retention of ingesta and its movement between compartments of the fore stomach.

    “The connecting chamber is oriented in a dorsal-toventral direction in the newborn to assist with passage of milk into the glandular stomach; the orientation changes in the adult to promote retention of ingesta and its movement between compartments of the fore stomach (Macdonald and Hartman 1983).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Macdonald and Hartman 1983 source
  • May combine two claims.

    Premisecitation

    Instead of infundibula and renculi, the lobes of C. liberiensis kidneys are projections like the fingers of a hand; each kidney has 17-25 lobes.

    “Instead, the lobes are projections like the fingers of a hand; each kidney has 17-25 lobes (Maluf 1978(Maluf , 1994)).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Maluf 1978 source
    • cites Maluf 1994 source
  • May combine two claims.

    Premisecitation

    The globe (eyeball) of C. liberiensis is rounded and slightly taller than it is wide; measurements from a subadult female (117 kg) were 24.3 mm horizontal diameter, 18.6 mm anterior to posterior diameter, and 22.5 mm vertical diameter.

    “The globe (eyeball) itself is rounded and slightly taller than it is wide; measurements from a subadult female (117 kg) were 24.3 mm horizontal diameter, 18.6 mm anterior to posterior diameter, and 22.5 mm vertical diameter (Hegner 1967).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Hegner 1967 source
  • May combine two claims.

    Premisecitation

    The species has also been confirmed in the southeast in Maryland and River Gee counties and within the proposed Grand Kru-River Gee Protected Area.

    “The species has also been confirmed in the southeast in Maryland and River Gee counties and within the proposed Grand Kru-River Gee Protected Area (Mallon et al. 2011).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Mallon et al. 2011

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    The tapetum lucidum of C. liberiensis is light blue, reflective, and extends across the majority of the fundus; the ventral aspect is grossly obscured by the pigmented epithelial cell layer of the retina and thus the functional tapetum primarily occupies the dorsal aspect of the fundus.

    “The tapetum lucidum is light blue, reflective, and extends across the majority of the fundus; the ventral aspect is grossly obscured by the pigmented epithelial cell layer of the retina and thus the functional tapetum primarily occupies the dorsal aspect of the fundus (Hegner 1967).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Hegner 1967 source
  • May combine two claims.

    Interpretationcitation

    C. liberiensis has low-crowned molars, further supporting its status as a forest-dwelling consumer of coarse vegetation.

    “C. liberiensis has low-crowned molars, further supporting its status as a forest-dwelling consumer of coarse vegetation (Weston 2000).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Weston 2000 source
  • May combine two claims.

    Premisecitation

    The entire small intestine (duodenum, jejunum, ileum) of an adult female C. liberiensis is about 16 m long with an average diameter of 2.5 cm; the colon is about 2.5 m long.

    “The entire small intestine (duodenum, jejunum, ileum) of an adult female is about 16 m long with an average diameter of 2.5 cm; the colon is about 2.5 m long (Macdonald and Hartman 1983).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Macdonald and Hartman 1983 source
  • May combine two claims.

    Premisenone given

    The eyes of C. liberiensis are less prominent and have a more lateral placement with a wider field of vision than with the dorsal eye placement of the amphibious common hippopotamus.

    “The eyes of C. liberiensis are less prominent and have a more lateral placement with a wider field of vision than with the dorsal eye placement of the amphibious common hippopotamus.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Premisenone given

    Similar conglomerate, bristle-like hairs are found only in seals and sea lions (Carnivora; Otariidae).

    “Similar conglomerate, bristle-like hairs are found only in seals and sea lions (Carnivora; Otariidae).”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Hair measurements (mm) for C. liberiensis were: up to 35 for lip hairs, 6-9 for ear hairs, and 10-18 for tail hairs.

    “Hair measurements (mm) for C. liberiensis were: up to 35 for lip hairs, 6-9 for ear hairs, and 10-18 for tail hairs (Lochte 1951).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Lochte 1951

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisenone given

    Fossil records support the much more recent presence of the now-extinct dwarf hippo species on the islands of Crete (Hippopotamus creutzburgi), Cyprus (Phanourios minor), and Madagascar (Hippopotamus madagascariensis).

    “Fossil records support the much more recent presence of the now-extinct dwarf hippo species on the islands of Crete (Hippopotamus creutzburgi), Cyprus (Phanourios minor), and Madagascar (Hippopotamus madagascariensis).”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Premisecitation

    The retina of C. liberiensis has two histologically distinct types of pigmented epithelial cells and three types of photoreceptor cells.

    “The retina itself has two histologically distinct types of pigmented epithelial cells and three types of photoreceptor cells (Hegner 1967).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Hegner 1967 source
  • May combine two claims.

    Premisecitation

    Each kidney of C. liberiensis has about three times 10^6 glomeruli; however, the total length of the tubule, including the Loop of Henle, is only 6.8 mm.

    “Each kidney has about three times 10 6 glomeruli (Maluf 1994); however, the total length of the tubule, including the Loop of Henle, is only 6.8 mm (Maluf 1978).”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites Maluf 1994 source
    • cites Maluf 1978 source
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    The earliest Hexaprotodon fossils, dating from the Mio-Pliocene period about 5 million years ago, were recovered from the Siwalik Hills on the India-Pakistan border.

    “The earliest Hexaprotodon fossils, dating from the Mio-Pliocene period about 5 million years ago, were recovered from the Siwalik Hills on the India-Pakistan border (Falconer and Cautley 1836).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Falconer and Cautley 1836

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    Multiple anecdotal reports describe white foamy skin secretions produced by the subdermal glands in wild C. liberiensis, and captive animals often exhibit the same secretions during periods of physical exertion, including during mating.

    “Multiple anecdotal reports describe white foamy skin secretions produced by the subdermal glands in wild C. liberiensis, and captive animals often exhibit the same secretions during periods of physical exertion, including during mating (Steinmetz 1937;Lang 1975;Schubert 2004;von Houwald et al. 2007).”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites Steinmetz 1937

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Lang 1975

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites von Houwald et al. 2007

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    An elongated triangular gall bladder is present in C. liberiensis, and the bile duct empties into the duodenum 15 cm distal to the pylorus.

    “An elongated triangular gall bladder is present, and the bile duct empties into the duodenum 15 cm distal to the pylorus (Macalister 1873;Langer 1975).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Macalister 1873

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Langer 1975 source
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    One animal was caught in a pit-trap near Tiwai Island in 2010.

    “One animal was also caught in a pit-trap near Tiwai Island in 2010 (Conway 2013).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Conway 2013

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Interpretationcitation

    This range is comparable to previously published rates for the common hippopotamus at the same temperatures, indicative of similar dermal physiology for the two species.

    “This range is comparable to previously published rates for the common hippopotamus at the same temperatures, indicative of similar dermal physiology for the two species (Olivier 1975).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Olivier 1975 source
  • May combine two claims.

    Premisenone given

    Field surveys conducted between 1982 and 1986 found signs of C. liberiensis within 21 protected areas in southwestern Côte d'Ivoire, with the highest abundances in Taï National Park and the surrounding N'Zo Faunal Reserve.

    “Field surveys conducted between 1982 and 1986 found signs of C. liberiensis within 21 protected areas in southwestern Côte d'Ivoire, with the highest abundances in Taï National Park and the surrounding N'Zo Faunal Reserve.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Premisecitation

    By the late 20th century, the distribution of C. liberiensis was limited to Sapo National Park and Grebo National Forest in the southeast, and North Lorma National Forest in the far northwest; it was deemed unlikely to persist in the central regions of Liberia.

    “However, by the late 20th century its distribution was limited to Sapo National Park and Grebo National Forest in the southeast, and North Lorma National Forest in the far northwest; it was deemed unlikely to persist in the central regions of Liberia (Anstey 1991a).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Anstey 1991a

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    The two kidneys equal 0.22% of body mass in the adult and 0.51-0.63% of body mass in the newborn C. liberiensis.

    “The two kidneys equal 0.22% of body mass in the adult and 0.51-0.63% of body mass in the newborn (Maluf 1994).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Maluf 1994 source
  • May combine two claims.

    Premisecitation

    A 2005 survey conducted in Gola, North Lorma, and Grebo National Forests in Liberia confirmed signs of C. liberiensis only in Grebo National Forest, in the far southeast near the border with Côte d'Ivoire; the other areas lacked evidence of its presence.

    “A 2005 survey conducted in Gola, North Lorma, and Grebo National Forests in Liberia confirmed signs of C. liberiensis only in Grebo National Forest, in the far southeast near the border with Côte d'Ivoire; the other areas lacked evidence of its presence (Barrie et al. 2007).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Barrie et al. 2007 source
  • May combine two claims.

    Premisecitation

    The mucosal epithelium of the fore stomachs is lined with finger-like papillae, each varying in length, thickness, and shape; these papillae are less prominent in the newborn.

    “The mucosal epithelium of the fore stomachs is lined with finger-like papillae, each varying in length, thickness, and shape; these papillae are less prominent in the newborn (Macdonald and Hartman 1983;Endo et al. 2001).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Macdonald and Hartman 1983 source
    • cites Endo et al. 2001 source
  • May combine two claims.

    Interpretationcitation

    The most westward extent of the range of C. liberiensis is likely the Ouatamba-Kilimi National Park in northwestern Sierra Leone, also the northernmost location where the species has been recorded, although there are no recent reports to substantiate its continued presence in this area.

    “The most westward extent of its range is likely the Ouatamba-Kilimi National Park in northwestern Sierra Leone (White 1986), also the northernmost location where the species has been recorded, although there are no recent reports to substantiate its continued presence in this area.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites White 1986

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    In Ziama, evidence of C. liberiensis (tracks and dung) was found along the Njéré, Gniogné, and upper Ouin watercourses, and in Diécké along the Nié, Grand Gbin, Gbin-bé, and Lih streams.

    “In Ziama, evidence of C. liberiensis (tracks and dung) was found along the Njéré, Gniogné, and upper Ouin watercourses, and in Diécké along the Nié, Grand Gbin, Gbin-bé, and Lih streams (Bützler 1994).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Bützler 1994

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    There is no cecum in C. liberiensis, but the junction between the large and small intestine is characterized by an increase in diameter and a change in the lining of the mucosal epithelium.

    “There is no cecum (Macalister 1873), but the junction between the large and small intestine is characterized by an increase in diameter and a change in the lining of the mucosal epithelium (Macdonald and Hartman 1983).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Macalister 1873

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Macdonald and Hartman 1983 source
  • May combine two claims.

    Premisecitation

    Lobulated kidneys of C. liberiensis are similar in architecture to those of the Bovidae but lack infundibula and renculi.

    “Lobulated kidneys are similar in architecture to those of the Bovidae but lack infundibula and renculi (Macalister 1873).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Macalister 1873

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based). May combine two claims.

    Premisenone given

    The hippopotamids are unique among the Artiodactyla in that they have retained a semiaquatic lifestyle and all four toes are weight-bearing.

    “The hippopotamids are unique among the Artiodactyla in that they have retained a semiaquatic lifestyle and all four toes are weight-bearing.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Premisecitation

    The pupil of C. liberiensis is oval, 7 mm wide and 5 mm high, with a symmetrical iris width of 2 mm; the lens is 10 mm in diameter and 7 mm thick; scleral thickness varies between 1.2 and 1.5 mm.

    “The pupil is oval, 7 mm wide and 5 mm high, with a symmetrical iris width of 2 mm; the lens is 10 mm in diameter and 7 mm thick; scleral thickness varies between 1.2 and 1.5 mm (Hegner 1967).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Hegner 1967 source
  • May combine two claims.

    Premisecitation

    Polycystic kidney disease, first noted as an incidental finding at necropsy, is now recognized as a possible X-linked dominant inheritance trait, with prevalence rates greater than 37% in captive animals.

    “Polycystic kidney disease, first noted as an incidental finding at necropsy (Jarofke and Klös 1982), is now recognized as a possible X-linked dominant inheritance trait, with prevalence rates greater than 37% in captive animals (Raymond et al. 2000;Nees et al. 2009;Flacke et al. 2017b).”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites Jarofke and Klös 1982

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Raymond et al. 2000

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Nees et al. 2009 source
  • May combine two claims.

    Premisecitation

    Communal housing of C. liberiensis can lead to conspecific aggression resulting in injury and death, may contribute to abnormal behaviors including stereotypies, and is also believed to compromise normal maternal behavior in some circumstances.

    “Communal housing can lead to conspecific aggression resulting in injury and death, may contribute to abnormal behaviors including stereotypies, and is also believed to compromise normal maternal behavior in some circumstances (Flacke et al. 2015).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Flacke et al. 2015 source
  • May combine two claims.

    Premisecitation

    C. liberiensis is found in both primary and secondary rainforests; low-lying Raphia palm swamps are its preferred habitat type because these offer both feeding and resting areas.

    “C. liberiensis is found in both primary and secondary rainforests; low-lying Raphia palm swamps are its preferred habitat type because these offer both feeding and resting areas (Robinson 1970;Bülow 1987).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Robinson 1970

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Bülow 1987

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisereasoning

    These measures of genetic diversity are calculated via analysis of studbook data, data that inaccurately assume equal relatedness among founders from wild populations, may contain errors in recorded pedigrees, and cannot clearly identify genetically underrepresented animals.

    “However, these measures of genetic diversity are calculated via analysis of studbook data, data that inaccurately assume equal relatedness among founders from wild populations, may contain errors in recorded pedigrees, and cannot clearly identify genetically underrepresented animals.”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Premisecitation

    Recently, 1.2 mg/kg ketamine and 0.08 mg/kg medetomidine followed by endotracheal intubation and maintenance on oxygen and isoflurane gas has proven very safe and effective for anesthesia of C. liberiensis, with no reported mortality.

    “Recently, 1.2 mg/kg ketamine and 0.08 mg/kg medetomidine followed by endotracheal intubation and maintenance on oxygen and isoflurane gas has proven very safe and effective for anesthesia, with no reported mortality (Bouts et al. 2012).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Bouts et al. 2012 source
  • May combine two claims.

    Premisecitation

    Very young C. liberiensis calves are hidden in a shallow pool or among the vegetation while the mother forages; she will visit the calf several times per day to allow it to nurse.

    “Very young calves are hidden in a shallow pool or among the vegetation while the mother forages; she will visit the calf several times per day to allow it to nurse (Galat-Luong 1981).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Galat-Luong 1981 source
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisenone given

    Very little is known about C. liberiensis in the wild, either at the level of the individual or the population.

    “Very little is known about Choeropsis liberiensis in the wild, either at the level of the individual or the population.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Premisecitation

    The species is highly dependent on streams and rivers, and is more widely distributed during the rainy season when water is more readily available.

    “The species is highly dependent on streams and rivers, and is more widely distributed during the rainy season when water is more readily available (Robinson 1969(Robinson , 1970)).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Robinson 1969

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Robinson 1970

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisereasoning

    Current assessments of wild C. liberiensis population numbers are largely unsubstantiated and based on qualitative data.

    “Population numbers for wild Choeropsis liberiensis are unknown; current assessments are largely unsubstantiated and based on qualitative data.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisenone given

    All reports of disease in C. liberiensis stem from the captive population.

    “All reports of disease in C. liberiensis stem from the captive population.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Premisecitation

    C. liberiensis is primarily solitary; its favorite elements are forest and swamps, and its activity patterns are principally nocturnal with occasional activity at dawn and dusk.

    “C. liberiensis is primarily solitary; its favorite elements are forest and swamps, and its activity patterns are principally nocturnal with occasional activity at dawn and dusk (Büttikofer 1890).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Büttikofer 1890

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Another survey reported between 3.6 (primary rainforest) and 2.9 (secondary rainforest) C. liberiensis per km2, extrapolated to between 8,200 and 14,200 within Taï National Park and its buffer zones.

    “Another survey based on radiotelemetry data for one female and extensive transect footprint counts reported between 3.6 (primary rainforest) and 2.9 (secondary rainforest) C. liberiensis per km 2 , and extrapolated to between 8,200 and 14,200 within Taï National Park and its buffer zones (Hentschel 1990).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Hentschel 1990

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    Population estimates for C. liberiensis range from 2,000 to 3,000 worldwide to possibly as many as 15,000 for Côte d'Ivoire alone.

    “Population estimates range from 2,000 to 3,000 worldwide (Eltringham 1993(Eltringham , 1999;;Ransom et al. 2015) to possibly as many as 15,000 for Côte d'Ivoire alone (Roth et al. 2004).”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites Eltringham 1993

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Ransom et al. 2015

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Roth et al. 2004 source
  • May combine two claims.

    Premisecitation

    The chorion of C. liberiensis is folded and its surface is covered with villi interspersed with rounded or irregularly shaped areolae; the villi are lined with columnar epithelium.

    “The chorion is folded and its surface is covered with villi interspersed with rounded or irregularly shaped areolae; the villi are lined with columnar epithelium (Macdonald and Bosma 1985).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Macdonald and Bosma 1985 source
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisenone given

    It is unknown if polycystic kidney disease is similarly prevalent in wild C. liberiensis populations.

    “It is unknown if the condition is similarly prevalent in wild populations.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Hybrids between C. liberiensis and the common hippopotamus do not occur.

    “Hybrids between C. liberiensis and the common hippopotamus do not occur (Benirschke 2007).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Benirschke 2007

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    Anesthesia for C. liberiensis can be challenging; difficulties include accurate weight estimation, selection of protocols, tough skin, thick subcutaneous fat, limited access to peripheral circulation, endotracheal intubation, bradycardia, hypoventilation, apnea, and a high fatality rate.

    “Anesthesia for C. liberiensis can be challenging; difficulties include accurate weight estimation for dosage calculations, selection of protocols for anesthetic drugs, tough skin that is challenging to penetrate with a needle or dart, a thick layer of subcutaneous fat leading to variable and systemic drug absorption, limited access to peripheral circulation, endotracheal intubation, bradycardia, h”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Miller 2007 source
    • cites Miller et al. 2014 source
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    The penis and prepuce of C. liberiensis curl caudally when not erect.

    “The penis and prepuce curl caudally when not erect (Pocock 1923).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Pocock 1923 source
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Interpretationcitation

    These assessments assume equal distribution of animals throughout all available areas of primary and secondary rainforest habitat and are likely to represent an overestimation of actual numbers.

    “These assessments assume equal distribution of animals throughout all available areas of primary and secondary rainforest habitat and are likely to represent an overestimation of actual numbers (K.M. Hentschel, pers.comm.).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites K.M. Hentschel, pers.comm.

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    The primary drivers of these land-use changes include increasing human population numbers, poor rural infrastructure and support services, and an often unstable political climate.

    “The primary drivers of these land-use changes include increasing human population numbers, poor rural infrastructure and support services, and an often unstable political climate (Norris et al. 2010).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Norris et al. 2010 source
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    The fetal placentas of three fullterm calves weighed 900-1,125 g.

    “The fetal placentas of three fullterm calves weighed 900-1,125 g (Benirschke 2007).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Benirschke 2007

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    Flach et al. (1998) reported a heart rate of 42-100 beats/min and respiratory rate of 0-10 breaths/min for an anesthetized female C. liberiensis.

    “Flach et al. (1998) reported a heart rate (beats/ min) of 42-100 and respiratory rate (breaths/min) of 0-10 for an anesthetized female.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Flach et al. 1998 source
  • May combine two claims.

    Premisecitation

    There are two types of villi in C. liberiensis: areolar, which are more blunted, less branched, broader and overlie the endometrial glands, and interareolar villi.

    “There are two types of villi: areolar, which are more blunted, less branched, broader and overlie the endometrial glands, and interareolar villi.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    The diploid (2n) chromosome number for C. liberiensis is 36, with all chromosomes being metacentric except for an acrocentric Y chromosome.

    “The diploid (2n) chromosome number for Choeropsis liberiensis is 36, with all chromosomes being metacentric except for an acrocentric Y chromosome (Hsu and Benirschke 1977).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Hsu and Benirschke 1977 source
  • May combine two claims.

    Premisecitation

    Overall, the limited information in the primary literature describes C. liberiensis as a generally solitary species inhabiting primary and secondary rainforest, with preferred habitat types including low-lying Raphia palm swamps and areas in close proximity to or partially submerged in water.

    “Overall, the limited information in the primary literature describes C. liberiensis as a generally solitary species inhabiting primary and secondary rainforest, with preferred habitat types including low-lying Raphia palm swamps and areas in close proximity to or partially submerged in water.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Premisecitation

    Mean values (n = 5 anesthetic episodes) from a juvenile female C. liberiensis were: pH 7.4; partial pressure of carbon dioxide 61.5 mmHg; partial pressure of oxygen 71 mmHg; bicarbonate 40.8 mmol/l; oxygen saturation 71.6%; end tidal carbon dioxide 42.5 mmHg; body temperature 36.3°C.

    “Mean values (n = 5 anesthetic episodes) from a juvenile female were: pH 7.4; partial pressure of carbon dioxide (mmHg), 61.5; partial pressure of oxygen (mmHg), 71; bicarbonate (mmol/l), 40.8; oxygen saturation, 71.6%; end tidal carbon dioxide (mmHg), 42.5; and body temperature (°C), 36.3 (Morris et al. 2001).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Morris et al. 2001

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationcitation

    This activity is thought to comprise a form of territory marking or intraspecific communication.

    “This activity is thought to comprise a form of territory marking or intraspecific communication (Lang 1975;Kranz 1982;Hentschel 1990;Robinson 1996;von Houwald et al. 2007).”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites Lang 1975

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Kranz 1982 source
    • cites Hentschel 1990

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    Values obtained from an anesthetized male C. liberiensis: average heart rate 60 beats/min; average respiratory rate 4 breaths/min; body temperature range 33.6-35.3°C; mean arterial hemoglobin saturation 95-99%.

    “The following values were obtained from an anesthetized male C. liberiensis: average heart rate (beats/ min) 60; average respiratory rate (breaths/min) 4; body temperature range (°C) 33.6-35.3;mean arterial hemoglobin saturation 95-99% (Weston et al. 1996).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Weston et al. 1996

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    Allometric scaling was used to estimate the heart rate of conscious C. liberiensis at 60-65 beats/min; heart rate data for conscious animals has otherwise not been reported.

    “Allometric scaling was used to estimate the heart rate (beats/min) of conscious animals at 60-65 (Bouts et al. 2012); heart rate data for conscious animals has otherwise not been reported.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Bouts et al. 2012 source
  • May combine two claims.

    Premisecitation

    A total of 120 animals, or two animals per linear kilometer of habitat, was reported from Azagny National Park based on transect footprint counts.

    “A total of 120 animals, or two animals per linear kilometer of habitat, was reported from Azagny National Park based on transect footprint counts (Bülow 1987).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Bülow 1987

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    Habitat descriptions for 409 locations at Gola confirmed the presence of C. liberiensis in farm bush areas (54.41%), forest (24.21%), rivers/streams/swamps (16.14%), with one record from a cocoa plantation.

    “Habitat descriptions for 409 locations based on search walks and camera traps at Gola Rainforest National Park, Sierra Leone, and Gola National Forest, Liberia, confirmed the presence of C. liberiensis in farm bush areas (243; 54.41%), forest (99; 24.21%), rivers, streams and swamps (66; 16.14%), with one record from a cocoa plantation (Hillers et al. 2016).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Hillers et al. 2016

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    The multifocal areas of squamous metaplasia on both umbilical cord and amniotic membranes are unique to the hippopotamids and appear strikingly pustular.

    “The multifocal areas of squamous metaplasia on both umbilical cord and amniotic membranes are unique to the hippopotamids and appear strikingly “pustular” (Macdonald and Bosma 1985;Benirschke 2007).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Macdonald and Bosma 1985 source
    • cites Benirschke 2007

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    The size of wild C. liberiensis populations remains unknown but is widely considered to be declining based on the evidence of continued habitat loss and reduced densities reported for Côte d'Ivoire.

    “The size of wild populations remains unknown but is widely considered to be declining based on the evidence of continued habitat loss and reduced densities reported for Côte d'Ivoire (Roth et al. 2004;Hoppe-Dominik et al. 2011).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Roth et al. 2004 source
    • cites Hoppe-Dominik et al. 2011 source
  • May combine two claims.

    Premisecitation

    C. liberiensis has diffuse epitheliochorial placentation and an umbilical cord with two arteries and two veins; however, a few specimens of C. liberiensis have only three umbilical vessels, two arteries and one vein.

    “Choeropsis liberiensis has diffuse epitheliochorial placentation and an umbilical cord with two arteries and two veins (Macdonald and Bosma 1985); however, a few specimens of C. liberiensis have only three umbilical vessels, two arteries and one vein (Benirschke 2007).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Macdonald and Bosma 1985 source
    • cites Benirschke 2007

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    The most commonly reported population estimate for C. liberiensis is ≤ 3,000; however, this figure originates from gray literature.

    “The most commonly reported population estimate for C. liberiensis is ≤ 3,000; however, this figure originates from gray literature (Eltringham 1993(Eltringham , 1999;;Lewison and Oliver 2008).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Eltringham 1993

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Lewison and Oliver 2008

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    Ejaculates from seven C. liberiensis had an average volume of 3.0 ± 0.9 (SEM) ml and a concentration of 2.1 ± 1.3 × 10^6 spermatozoa per ml.

    “Ejaculates from seven C. liberiensis had an average volume of 3.0 ± 0.9 (SEM) ml and a concentration of 2.1 ± 1.3 × 10 6 spermatozoa per ml (Saragusty et al. 2010).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Saragusty et al. 2010 source
  • May combine two claims.

    Premisecitation

    The only studies using radiotelemetry to evaluate home range size for C. liberiensis indicated an average female (n = 5) territory size of 40-60 ha and a male (n = 1) territory of 120 ha.

    “The only studies using radiotelemetry to evaluate home range size for C. liberiensis indicated an average female (n = 5) territory size of 40-60 ha and a male (n = 1) territory of 120 ha (Bülow 1987;Hentschel 1990).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Bülow 1987

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Hentschel 1990

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisenone given

    C. liberiensis forages primarily on dry land but does not rely on grass for its nutritional intake.

    “Choeropsis liberiensis forages primarily on dry land but does not rely on grass for its nutritional intake.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Premisenone given

    Metabolite concentrations of progesterone in the saliva during the same time period were one-third to one-half of those in skin secretions, but the trends were comparable.

    “Metabolite concentrations of progesterone in the saliva during the same time period were one-third to one-half of those in skin secretions, but the trends were comparable.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Premisecitation

    Variables contributing to potential inaccuracy in population estimates include the inability to discern individual animals, the skill of detecting footprints and droppings, the decomposition rate of feces, and defecation rates.

    “Variables contributing to potential inaccuracy include the inability to discern individual animals from camera trap footage or footprints, the skill of detecting footprints and droppings, the decomposition rate of the feces, and defecation rates (Bülow 1987;Roth et al. 2004).”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites Bülow 1987

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Roth et al. 2004 source
  • May combine two claims.

    Premisecitation

    The captive population at the end of 2015 (n = 377), believed to be derived from 60 founders, had an average inbreeding coefficient of 0.0600, an average mean kinship of 0.0305, and gene diversity of 0.9695.

    “The captive population at the end of 2015 (n = 377), believed to be derived from 60 founders, had an average inbreeding coefficient of 0.0600, an average mean kinship of 0.0305, and gene diversity of 0.9695 (Steck 2016).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Steck 2016

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    The reproductive anatomy of C. liberiensis has not been extensively detailed for either sex, although in many aspects it is likely to be similar to that of the common hippopotamus.

    “The reproductive anatomy of C. liberiensis has not been extensively detailed for either sex, although in many aspects it is likely to be similar to that of the common hippopotamus (Macdonald 2007).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Macdonald 2007

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    Data from 14 immobilized adult C. liberiensis were: mean heart rate 34 ± 7 beats/min; mean respiratory rate 14 ± 6 breaths/min; mean peripheral hemoglobin saturation 91-92% for animals receiving supplemental oxygen; mean end tidal carbon dioxide 55 ± 10 mmHg.

    “Data from 14 immobilized adults were as follows: mean heart rate (beats/min ± SD) 34 ± 7; mean respiratory rate (breaths/min ± SD), 14 ± 6; mean peripheral hemoglobin saturation, 91-92% for animals receiving supplemental oxygen; mean end tidal carbon dioxide (mmHg ± SD), 55 ± 10 ( Bouts et al. 2012).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Bouts et al. 2012 source
  • The quote only partly states this claim.

    Premisecitation

    Higher birth weights are positively correlated with survival rate beyond 3 months of age.

    “Higher birth weights were positively correlated with survival rate beyond 3 months of age.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Leutenegger 1978 source
  • Probably not a substantial claim: may not pass S2 (checkable). May combine two claims.

    Interpretationcitation

    C. liberiensis can serve as a flagship species for the Upper Guinean forest ecosystem, thus promoting sustainable and accountable land use; expansion, protection, and management of national parks and a highly viable platform on which to raise public awareness of this little known biodiversity hotspot.

    “C. liberiensis can serve as a flagship species for the Upper Guinean forest ecosystem, thus promoting sustainable and accountable land use; expansion, protection, and management of national parks and a highly viable platform on which to raise public awareness of this little known biodiversity hotspot (Mallon et al. 2011;Fauna and Flora International and Forestry Development Authority 2013).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Mallon et al. 2011

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Fauna and Flora International and Forestry Development Authority 2013

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Interpretationcitation

    Sex ratio varies among zoos, and thus husbandry factors associated with captivity are likely to play at least a partial role in the bias.

    “Sex ratio varies among zoos, and thus husbandry factors associated with captivity are likely to play at least a partial role in the bias (Zschokke 2002;Boonyarittichaikij 2010;Flacke et al. 2015).”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites Zschokke 2002 source
    • cites Boonyarittichaikij 2010

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Flacke et al. 2015 source
  • May combine two claims.

    Premisecitation

    The largest remaining legally protected, contiguous tract of Upper Guinean forest ecosystem lies within the Taï National Park and surrounding N'Zo Faunal Reserve; this area is believed to hold the largest remaining wild population of C. liberiensis.

    “The largest remaining legally protected, contiguous tract of Upper Guinean forest ecosystem lies within the Taï National Park and surrounding N'Zo Faunal Reserve; this area is believed to hold the largest remaining wild population (Critical Ecosystem Partnership Fund 2015;Mallon et al. 2011).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Critical Ecosystem Partnership Fund 2015

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Mallon et al. 2011

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisenone given

    It is unknown if the female-biased sex ratio in captive C. liberiensis is an artifact of captivity or a reflection of normal biology for this species.

    “It is unknown if the femalebiased sex ratio is an artifact of captivity or a reflection of normal biology for this species.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationcitation

    The Krahn-Bassa/Sapo/Grebo/Taï complex spanning the border of Liberia and Côte d'Ivoire represents the greatest opportunity to establish and maintain protected areas with large intact stands of forest.

    “The Krahn-Bassa/Sapo/Grebo/Taï complex spanning the border of Liberia and Côte d'Ivoire represents the greatest opportunity to establish and maintain protected areas with large intact stands of forest (Critical Ecosystem Partnership Fund 2015;Fauna and Flora International and Forestry Development Authority 2013).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Critical Ecosystem Partnership Fund 2015

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Fauna and Flora International and Forestry Development Authority 2013

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

122 of 122
  • The paper relies on this without support.

    It is universally accepted that C. liberiensis numbers are limited.

    “However, it is universally accepted that numbers are limited.”
  • The paper relies on this without support.

    Zoos generally provide the entire ration for C. liberiensis as one or two daily feedings.

    “in contrast, zoos generally provide the entire ration as one or two daily feedings.”
  • The paper relies on this without support.

    Stress levels immediately prior to immobilization play an important role in the variability of success experienced with anesthesia protocols for C. liberiensis, especially when alpha-2 agonists are used.

    “Stress levels immediately prior to immobilization play an important role in the variability of success experienced with these anesthesia protocols, especially when alpha-2 agonists are used.”
3 of 3

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Nigerian taxon is called both a subspecies and a species

    Minor

    The paper recognizes heslopi as a subspecies of C. liberiensis, but later calls it the species C. heslopi without indicating a change in taxonomic treatment.

  • Farm-bush percentage does not match the location count

    Minor

    Farm-bush records account for 243 of 409 locations, or 59.41%, not 54.41%.

    Reported 54.41 · recomputed 59.413203

  • Eyeball measurements show greater width than height

    Minor

    The description says the eyeball is taller than it is wide, whereas its stated horizontal diameter, 24.3 mm, exceeds its vertical diameter, 22.5 mm.

  • Wild male weight is reported, then excluded

    Minor

    The diagnosis gives a recorded weight for a wild adult male, but the general characters section says wild body-mass measurements exist only for two females.

  • Cited juvenile blood-gas study concerns the other hippo species

    Minor

    The juvenile female's measurements are presented among C. liberiensis physiological values, but the cited reference identifies its subject as an East African river hippopotamus.

5 of 5

Cites

Flagged first, then by citations

Research works printed but not linked: 87

  1. Anstey, 1991, Large mammal distribution in Liberia: the findings of a preliminary national survey 1989–1990. World Wildlife Fund and Forest Development Authority Wildlife Survey Report
  2. Anstey, 1991, Wildlife utilisation in Liberia: the findings of a national survey 1989–1990. World Wildlife Fund and Forest Development Authority Wildlife Survey Report
  3. Benirschke, 2007, East African river hippopotamus & pygmy hippopotamus.
  4. Blaszkiewitz, 1983, Haltung und Zucht des Zwergflußpferdes (Choeropsis liberiensis Morton 1849) im Zoologischen Garten Berlin, Bongo, 7, 71
  5. Boever, 1978, Artiodactyla., 771
  6. Bogui, 2016, Distribution of pygmy hippopotamus (Choeropsis liberiensis) in Taï National Park, Ivory Coast: influences of natural and anthropogenic factors, International Journal of Research in Biosciences, 5, 27
  7. Boonyarittichaikij, 2010, Studying the effect of factors that potentially influence the sex ratio of captive pygmy hippopotamus (Choeropsis liberiensis)
  8. Bülow, 1987, Untersuchungen am Zwergflußpferd, Choeropsis liberiensis im Azagny - Nationalpark, Elfenbeinküste
  9. Bush, 1972, Prolapsed uterus in a pygmy hippopotamus, Journal of the American Veterinary Medical Association, 140, 651
  10. Bützler, 1994, Choeropsis liberiensis pygmy hippopotamus., 65
  11. Cohrs, 1952, Protozoen als Ursache wiederholter Fehlgeburten beim Zwergflußpferd (Choeropsis liberiensis), Der Zoologische Garten NF, 19, 192
  12. Coryndon, 1977, The taxonomy and nomenclature of the Hippopotamidae (Mammalia, Artiodactyla) and a description of a two new fossil species, Proceedings of the Royal Netherlands Academy of Arts and Sciences B, 80, 61
  13. Cracknell, J. M., M.Stidworthy, and A.Holliman. 2011. Leptospirosis in a pygmy hippopotamus (Choeropsis liberiensis). Pp. 35–37 in Proceedings of the American Association of Zoo Veterinarians Annual Conference, Kansas City, Missouri.
  14. Crandall, 1964, Hippopotamuses., 530
  15. Dathe, 1989, Progesteronnachweis in Sekreten des Zwergflußpferdes (Choeropsis liberiensis Morton, 1844), Der Zoologische Garten NF, 59, 201
  16. Dekeyser, 1955, Les mammifères de l’Afrique Noire Française
  17. Duvernoy, 1849, Troisième note sur les espèces d’Hippopotames, Comptes Rendus De L’Académe des Sciences. Paris, 29, 276
  18. Eltringham, 1993, The pygmy hippopotamus (Hexaprotodon liberiensis)., 55
  19. Eshuis, 2011, Habitat preference and activity pattern of the pygmy hippopotamus analyzed by camera trapping and GIS
  20. Eulenberger, 1995, Flußpferde., 246
  21. Fábián, 1976, Darmpech-Obstipation („Fohlenkolik“) bei neugeborenem Zwergflußpferd, Choeropsis liberiensis, Der Zoologische Garten NF, 46, 452
  22. Falconer, 1836, Note on the fossil hippopotamus of the Siwalik Hills, 39
  23. Fauna and Flora International and Forestry Development Authority, 2013, National action plan for the conservation of the pygmy hippopotamus in Liberia
  24. Gansloßer, 2008, Das Zwergflusspferd., 371
  25. Gippoliti, 1999, The pygmy hippopotamus at Rome Zoological Garden, International Zoo News, 46, 335
  26. Graf, 1981, Über den Verlust eines Zwergflußpferdes im Budapester Zoo, Erkrankungen der Zootiere: Verhandlungsbericht, 23, 389
  27. Gratiolet, 1867, Recherches sur l’Anatomie de l’Hippopotame
  28. Gray, 1974, Malocclusion in a pygmy hippopotamus, 41
  29. Greed, G. R . 1983. Husbandry and breeding of the pigmy hippopotamus (Choeropsis liberiensis). Pp. 10–23 in Proceedings Symposium 7, Association of British Wild Animal Keepers.
  30. Greengrass, 2011, Exploring the dynamics of bushmeat hunting and trade in Sapo National Park
  31. Hediger, 1946, Die Baseler Zwergflußpferd-Zucht, Zoologischer Garten Basel, 74, 23
  32. Hentschel, 1990, Untersuchung zu Status, Ökologie und Erhaltung des Zwergflusspferdes (Choeropsis liberiensis) in der Elfenbeinküste
  33. Heslop, 1944, The pigmy hippopotamus, 588
  34. Heslop, 1945, The pigmy hippopotamus in Nigeria, 629
  35. van Heukelum, 2011, In search of the elusive pygmy hippo; establishment of methods to determine population structure of pygmy hippos in Taï National Park, and assessment of their role in seed dispersal
  36. Heuschele, W. P., L. G.Doyle, P. A.Hooker, K. L.Gottling, and P. S.Kawanabe. 1982. Current status of some important viruses of domestic ruminants in captive wild ruminants in the USA. Pp. 94–121 in Proceedings of the American Association of Zoo Veterinarians Annual Conference, New Orleans, Louisiana.
  37. Hillers, 2010, Pygmy Hippo Conservation Project within the “Across the River – A Transboundary Peace Park for Sierra Leone and Liberia” Project (ARTP)
  38. Hornaday, 1920, Birth of a pygmy hippopotamus, New York Zoological Society Bulletin, 23, 11
  39. von Houwald, 2007, Husbandry guidelines for the pygmy hippopotamus (Hexaprotodon liberiensis)
  40. Hsu, 1977, Order: Artiodactyla, Family: Hippopotamidae.
  41. Jarofke, 1993, Hippopotamidae (hippopotamus)., 522
  42. Klingel, 1990, Hippopotamuses (genus Hippopotamus)., 64
  43. Kumar, 1990, Anaesthesia and repair of a ventral hernia in a pygmy hippopotamus (Choeropsis liberiensis), Indian Veterinary Journal, 67, 166
  44. Lang, 1975, Das Zwergflußpferd. Die Neue Brehm-Bücherei
  45. Laws, 1984, Hippopotamuses., 506
  46. Leidy, 1852, Attribution of Hippopotamus liberiensis to a new genus, Proceedings of the Academy of Natural Sciences, 6, 52
  47. Leidy, 1853, On the osteology of the head of hippopotamus, and a description of the osteological characters of a new genus of Hippopotamidæ, Journal of the Academy of Natural Sciences of Philadelphia, 2, 207
  48. Lewison, 2011, Family Hippopotamidae., 308
  49. Lindau, 1982, Hippopotamuses., 216
  50. Lochte, 1951, Untersuchungen an Haaren eines neugeborenen Nilpferdes und eines Zwergflußpferdes, Der Zoologische Garten NF, 18, 119
  51. Lydekker, 1908, The pigmy hippopotamus of West Africa, Country Life, 24, 473
  52. Macalister, 1873, The anatomy of Choeropsis liberiensis, Proceedings of the Royal Irish Academy, 2, 494
  53. Macdonald, 2007, The reproductive biology of the pigmy hippopotamus (Choeropsis liberiensis) with comparative observation on the common hippopotamus (Hippopotamus amphibious)., 86
  54. Mbaya, 2008, Captive wild animals as potential reservoirs of haemo and ectoparasitic infections of man and domestic animals in the arid-region of Northeastern Nigeria, Veterinarski Arhiv, 78, 429
  55. Miller, 2003, Hippopotamidae (hippopotamus)., 602
  56. Morris, 2001, Chemical restraint of juvenile east African river hippopotamus (Hippopotamus amphibius kiboko) at the San Diego Zoo., 10
  57. Morton, 1849, Additional observations on a new species of hippopotamus of Western Africa (Hippopotamus liberiensis), Journal of the Academy of Natural Sciences of Philadelphia, 2nd Series, 1, 3
  58. Osakwe, 1988, Management of pigmy hippopotamus and West African manatee in Jos Wildlife Park, The Nigerian Field, 53, 175
  59. Partridge, 1983, The management of the pygmy hippopotamus (Choeropsis liberiensis) at Bristol Zoo, International Zoo News, 30, 28
  60. Robinson, 1969, No. 204. Pygmy hippopotamus - ecological survey in West Africa., 123
  61. Robinson, 1970, The status of the pygmy hippopotamus and other wildlife in West Africa
  62. Robinson, 1979, Searching for Nimwe: the elusive pigmy hippo, Zoonooz, 52, 7
  63. Robinson, 1981, The reported use of denning structures by the pygmy hippopotamus Choeropsis liberiensis, Mammalia, 45, 506
  64. Robinson, 1996, River horses and water cows, The Pepper Bird (Publication of the Society for the Renewal of Nature and Conservation in Liberia-USA), 2, 5
  65. Robinson, 2013, Choeropsis liberiensis pygmy hippopotamus., 80
  66. Robinson, 2017, The pygmy hippo story – West Africa’s enigma of the rainforest
  67. Robinson, 1999, Survey and preparation of a preliminary conservation plan for the Cestos-Senkwehn riversheds of South-eastern Liberia. Report on the World Bank-World Wildlife Fund Global Forest Alliance WildInvest Project: January–March 1999
  68. Roth, 1962, Mitteilung über die Zwergflußpferdzucht in Gelsenkirchen, Der Zoologische Garten NF, 26, 327
  69. Roth, 1986, Vorkommen und relative Häufigkeit von Säugetieren im Tai-Regenwald der Elfenbeinküste, Säugetierkundliche Mitteilungen, 33, 171
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Cited by

Sorted by citations

Authors
Flacke, G. L., & Decher, J.
Affiliations
  • The University of Western Australia (AU)
  • Zoological Research Museum Alexander Koenig (DE)
Corresponding author
Flacke, Gabriella L
Venue
Mammalian Species
Published
2019-12-06
Volume
51
Issue
982
Pages
100-118
ISSN
  • 0076-3519 (ISSN-L)
  • 1545-1410
OpenAlex
W2992598458
Cited by
9
References
101
Citations by year
2026: 2 · 2024: 2 · 2023: 3 · 2022: 1 · 2021: 1
FWCI
0.30
Type
journal article
Language
en
Open access
Locations
  • Mammalian Species (publishedVersion)
  • Zenodo (CERN European Organization for Nuclear Research) (submittedVersion)
Funders
Rheinische Friedrich-Wilhelms-Universität Bonn
Topics
  • Physical Sciences › Environmental Science › Ecology › Wildlife Ecology and Conservation
  • Health Sciences › Veterinary › Small Animals › Animal Behavior and Welfare Studies
  • Social Sciences › Psychology › Social Psychology › Primate Behavior and Ecology
Keywords
Choeropsis liberiensis, pygmy hippopotamus, hippopotamus, threatened species, zoological collections, private collections, CITES Appendix II, conservation status

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Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

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