Open main menu
Home
Random
Recent changes
Special pages
Community portal
Preferences
About Wikipedia
Disclaimers
Incubator escapee wiki
Search
User menu
Talk
Dark mode
Contributions
Create account
Log in
Editing
Pygmy hippopotamus
Warning:
You are not logged in. Your IP address will be publicly visible if you make any edits. If you
log in
or
create an account
, your edits will be attributed to your username, along with other benefits.
Anti-spam check. Do
not
fill this in!
{{Short description|Small species of hippopotamus}} {{pp-move-indef}} {{Speciesbox | name = Pygmy hippopotamus | image = Hexaprotodon liberiensis in Edinburgh Zoo.JPG | image_caption = A pygmy hippopotamus at [[Edinburgh Zoo]] | status = EN | status_system = IUCN3.1 | status_ref = <ref name=Redlist>{{cite iucn |author=Ransom, C. |author2=Robinson, P.T. |author3=Collen, B. |year=2015 |title=''Choeropsis liberiensis'' |volume=2015 |page=e.T10032A18567171 |doi=10.2305/IUCN.UK.2015-2.RLTS.T10032A18567171.en |access-date=27 August 2021}}</ref> | status2 = CITES_A2 | status2_system = CITES | status2_ref = <ref>{{Cite web|title=Appendices {{!}} CITES|url=https://cites.org/eng/app/appendices.php|access-date=2022-01-14|website=cites.org}}</ref> | display_parents = 2 | genus = Choeropsis | parent_authority = [[Joseph Leidy|Leidy]], 1853 | species = liberiensis | authority = ([[Samuel George Morton|Morton]], 1849)<ref name=ASM/> | subdivision_ranks = Subspecies | subdivision = *''C. l. liberiensis'' <small></small> *''C. l. heslopi'' <small></small> | range_map = Pygmy hippopotamus range updated.svg | range_map_caption = Range map<ref name="Redlist"/> | synonyms = *''Hexaprotodon liberiensis'' <small></small> | synonyms_ref = <ref name=Redlist/> }}The '''pygmy hippopotamus''' or '''pygmy hippo''' ('''''Choeropsis liberiensis''''') is a small [[Hippopotamidae|hippopotamid]] which is native to the forests and swamps of [[West Africa]], primarily in [[Liberia]], with small populations in [[Sierra Leone]], [[Guinea]], and [[Ivory Coast]]. It has been [[extirpated]] from [[Nigeria]].<ref name=Redlist/> The pygmy hippopotamus is reclusive and [[nocturnal]]. It is one of only two extant species in the [[family (biology)|family]] [[Hippopotamidae]], the other being its much larger relative, the common [[hippopotamus]] (''Hippopotamus amphibius'') or Nile hippopotamus. The pygmy hippopotamus displays many terrestrial [[adaptation]]s, but like the common hippopotamus, it is semiaquatic and relies on water to keep its skin moist and its body temperature cool. Behaviors such as mating and giving birth may occur in water or on land. The pygmy hippopotamus is herbivorous, feeding on ferns, [[dicotyledons|broad-leaved plants]], [[grass]]es, and [[fruit]]s it finds in the forests. A rare [[nocturnal]] forest creature, the pygmy hippopotamus is a difficult animal to study in the wild. Pygmy hippos were unknown outside West Africa until the 19th century. Introduced to zoos in the early 20th century, they breed well in captivity and the vast majority of research is derived from zoo specimens.<ref name="Stroman 1972">{{cite journal|last1=Stroman|first1=H. R.|last2=Slaughter|first2=L. M.|title=The care and breeding of the Pygmy hippopotamus (''Choeropsis liberiensis'') in captivity|journal=International Zoo Yearbook|date=January 1972|volume=12|issue=1|pages=126β131|doi=10.1111/j.1748-1090.1972.tb02296.x}}</ref> The survival of the species in captivity is more assured than in the wild; in a 2015 assessment, the [[International Union for Conservation of Nature]] estimated that fewer than 2,500 pygmy hippos remain in the wild.<ref name=Redlist/> Pygmy hippos are primarily threatened by [[loss of habitat]], as forests are logged and converted to farm land, and are also vulnerable to [[poaching]], hunting for [[bushmeat]], natural predators, and war. Pygmy hippos are among the species [[Environmental issues in Liberia|illegally hunted for food in Liberia]]. == Taxonomy and origins == [[File:Hexaprotodon liberiensis Lagos Zoo Portugal (3).jpg|thumb|Showing its teeth at the [[Lagos, Portugal|Lagos]] Zoo in [[Portugal]] |left]]Nomenclature of the pygmy hippopotamus reflects that of the [[Hippopotamus#Taxonomy and origins|hippopotamus]]; the plural form is pygmy hippopotamuses or pygmy hippopotami.<ref>{{Cite web|url=https://www.thefreedictionary.com/Hippopotamus|title = Hippopotamus}}</ref> A male pygmy hippopotamus is known as a ''bull'', a female as a ''cow'', and a baby as a ''calf''. A group of hippopotami is known as a ''herd'' or a ''bloat''.<ref>[[List of animal names]]</ref> The pygmy hippopotamus is a member of the family [[Hippopotamidae]] where it is classified as a member of the [[genus]] ''Choeropsis'' ("resembling a [[Pig|hog]]"). Members of Hippopotamidae are sometimes known as hippopotamids. Sometimes the sub-family Hippopotaminae is used. Further, some taxonomists group hippopotami and [[anthracotheres]] in the superfamily Anthracotheroidea or Hippopotamoidea. The [[Taxonomy (biology)|taxonomy]] of the genus of the pygmy hippopotamus has changed as understanding of the animal has developed.<ref name="Redlist"/><ref name="Linnean"/><ref name="The Hippos"/><ref name=Robinson/> [[Samuel G. Morton]] initially classified the animal as ''Hippopotamus minor'', but later determined it was distinct enough to warrant its own genus, and labeled it ''Choeropsis''. In 1977, [[Shirley C. Coryndon]] proposed that the pygmy hippopotamus was closely related to ''[[Hexaprotodon]]'', a genus that consisted of prehistoric hippos mostly native to Asia.<ref name=Coryndon/> [[File:Pygmy Hippopotamus Skull.jpg|thumb|Skull]]This assertion was widely accepted,<ref name="Redlist"/><ref name="Linnean"/><ref name="The Hippos"/><ref name=Robinson/> until Boisserie asserted in 2005 that the pygmy hippopotamus was not a member of ''Hexaprotodon'', after a thorough examination of the phylogeny of Hippopotamidae. He suggested instead that the pygmy hippopotamus was a distinct genus, and returned the animal to ''Choeropsis''.<ref name="Linnean"/><ref name="Cetartiodactyla"/><ref name="Origins"/> [[ITIS]] verifies ''Hexaprotodon liberiensis'' as the valid [[scientific name]].<ref name="ITIS">{{cite web |title=ITIS Standard Report Page: ''Hexaprotodon liberiensis'' |url=https://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=625022#null |website=www.itis.gov |access-date=7 December 2020}}</ref> All agree that the modern pygmy hippopotamus, be it ''H. liberiensis'' or ''C. liberiensis'', is the only extant member of its genus.<ref name="Linnean">{{cite journal |last=Boisserie |first=Jean-Renaud |year=2005 |title=The phylogeny and taxonomy of Hippopotamidae (Mammalia: Artiodactyla): a review based on morphology and cladistic analysis |journal=[[Zoological Journal of the Linnean Society]] |volume= 143 |pages= 1β26 | doi = 10.1111/j.1096-3642.2004.00138.x|doi-access=free }}</ref><ref name=Coryndon>{{Cite journal |first=Shirley C.|last=Coryndon| title = The taxonomy and nomenclature of the Hippopotamidae (Mammalia, Artiodactyla) and a description of two new fossil species | year = 1977 | volume = 80 | issue = 2 | journal = Proceedings of the Koninklijke Nederlandse Akademie van Wetenschappen | pages = 61β88}}</ref> The [[American Society of Mammalogists]] moved it back to ''Choeropsis'' in 2021,<ref name=ASM>{{BioRef|asm|id=1006389|title=''Choeropsis liberiensis'' |version=1.5 |access-date=26 August 2021}}</ref> a move supported by the [[IUCN]].<ref name=Redlist/> === Nigerian subspecies === A distinct subspecies of pygmy hippopotamus existed in Nigeria until at least the 20th century, though the validity of this has been questioned.<ref name="Redlist"/> The existence of the subspecies, makes ''Choeropsis liberiensis liberiensis'' (or ''Hexaprotodon liberiensis liberiensis'' under the old classification) the full [[trinomen|trinomial nomenclature]] for the Liberian pygmy hippopotamus. The Nigerian pygmy hippopotamus was never studied in the wild and never captured. All research and all zoo specimens are the Liberian subspecies. The Nigerian subspecies is classified as ''C. liberiensis heslopi''.<ref name="The Hippos"/> The Nigerian pygmy hippopotamus ranged in the [[Niger River|Niger River Delta]], especially near [[Port Harcourt]], but no reliable reports exist after the collection of the museum specimens secured by [[Ian Heslop]], a British colonial officer, in the early 1940s. It is probably extinct.<ref name="Redlist"/> The subspecies is separated by over {{convert|1800|km|mi|abbr=on}} and the [[Dahomey Gap]], a region of savanna that divides the forest regions of West Africa. The subspecies is named after Heslop, who shot three members of it in 1935 and 1943.<ref name=Enigma>{{cite book|author-last1=Robinson| author-first1=Phillip T.|author-last2=Flacke| author-first2=Gabriella L.| author-last3=Hentschel| author-first3= Knut M.| year=2017| title=The Pygmy Hippo Story: West Africa's Enigma of the Rainforest| publisher=Oxford University Press| place=Oxford| isbn=978-0-19-061185-9|pages=61, 65}}</ref> He estimated that perhaps no more than 30 pygmy hippos remained in the region.<ref name=Action>{{Cite web | url = http://www.iucn.org/themes/ssc/sgs/pphsg/APchap3-3.htm | archive-url = https://archive.today/20080105044155/http://www.iucn.org/themes/ssc/sgs/pphsg/APchap3-3.htm | url-status = dead | archive-date = 2008-01-05 | title = Pigs, Peccaries and Hippos Status Survey and Action Plan | year = 1993 | access-date = 2008-08-23 | work = [[World Conservation Union]] status survey | author = Eltringham, S. Keith}}</ref> Heslop sent four pygmy hippopotamus skulls he collected to the [[British Museum of Natural History]] in London. These specimens were not subjected to taxonomic evaluation, however, until 1969 when {{Ill|Gordon Barclay Corbet|de}} classified the skulls as belonging to a separate subspecies based on consistent variations in the proportions of the skulls.<ref name=Corbet>{{Cite journal| title = The taxonomic status of the pygmy hippopotamus, Choeropsis liberiensis, from the Niger Delta | author = Corbet, G. B. | journal = [[Journal of Zoology]] | year = 1969 | volume = 158 | issue = 3 | pages = 387β394| doi = 10.1111/j.1469-7998.1969.tb02156.x}}</ref> The Nigerian pygmy hippos were seen or shot in [[Rivers State]], [[Imo State]] and [[Bayelsa State]], [[Nigeria]]. While some local humans are aware that the species once existed, its history in the region is poorly documented.<ref name="The Hippos"/> === Evolution === {{main|Hippopotamus#Evolution}} [[File:Anthracotherium magnum.jpg|thumb|[[Anthracothere]]s like ''[[Anthracotherium]]'' resembled pygmy hippos and are among their likely ancestors.]] The evolution of the pygmy hippopotamus is most often studied in the context of its larger cousin. Both species were long believed to be most closely related to the family [[Suidae]] ([[pig]]s and hogs) or Tayassuidae ([[peccaries]]), but research within the last 10 years has determined that pygmy hippos and hippos are most closely related to [[cetacea]]ns ([[whale]]s and [[dolphin]]s). Hippos and whales shared a common semi-aquatic ancestor that branched off from other artiodactyls around {{mya|60|mya}}.<ref name="ScienceNews">{{Cite web|title=Scientists find missing link between the dolphin, whale and its closest relative, the hippo |date=2005-01-25 |access-date=2008-08-23 |url=http://www.sciencenewsdaily.org/story-2806.html |work=Science News Daily |url-status=dead |archive-url=https://web.archive.org/web/20070304214747/http://www.sciencenewsdaily.org/story-2806.html |archive-date=2007-03-04 }}</ref><ref name="DNA">{{Cite journal | title = More DNA support for a Cetacea/Hippopotamidae clade: the blood-clotting protein gene gamma-fibrinogen | author = Gatesy, J | journal = [[Molecular Biology and Evolution]] | volume = 14 | pages = 537β543 | pmid = 9159931 | issue = 5 | date=1 May 1997 | doi=10.1093/oxfordjournals.molbev.a025790| doi-access = free }}</ref> This hypothesized ancestor likely split into two branches about six million years later.<ref name="Genomes">{{Cite journal | title = Analyses of mitochondrial genomes strongly support a hippopotamus-whale clade | volume = 265 | issue = 1412 | year = 1998 | pages = 2251β5 | journal = [[Proceedings of the Royal Society]] | author = Ursing, B.M. |author2=U. Arnason | doi = 10.1098/rspb.1998.0567 | pmid = 9881471 | pmc = 1689531}}</ref> One branch would [[Evolution of cetaceans|evolve into cetaceans]], the other branch became the [[anthracotheriidae|anthracotheres]], a large family of four-legged beasts, whose earliest member, from the Late [[Eocene]], would have resembled narrow hippopotami with comparatively small and thin heads.<ref name="Cetartiodactyla">{{cite journal |last=Boisserie |first=Jean-Renaud |author2= Fabrice Lihoreau |author3=Michel Brunet |date=February 2005|title= The position of Hippopotamidae within Cetartiodactyla|journal= [[Proceedings of the National Academy of Sciences]] |volume= 102 |issue= 5|pages= 1537β1541|doi= 10.1073/pnas.0409518102|pmid= 15677331 |pmc=547867|bibcode=2005PNAS..102.1537B |doi-access=free }}</ref> Hippopotamids are deeply nested within the family [[Anthracotheriidae]]. The oldest known hippopotamid is the genus ''[[Kenyapotamus]]'', which lived in Africa from {{mya|16|8|mya}}. ''Kenyapotamus'' is known only through fragmentary fossils, but was similar in size to ''C. liberiensis''.<ref name="Origins">{{cite journal | last= Boisserie | first=Jean-Renaud | author2=Fabrice Lihoreau |author3=Michel Brunet |date=March 2005 |title=Origins of Hippopotamidae (Mammalia, Cetartiodactyla): towards resolution |journal=[[Zoologica Scripta]] |volume= 34|issue= 2|pages=119β143 | doi = 10.1111/j.1463-6409.2005.00183.x | s2cid=83768668 }}</ref> The Hippopotamidae are believed to have evolved in Africa, and while at one point the species spread across Asia and Europe, no hippopotami have ever been discovered in the Americas. Starting {{mya|7.5|1.8|mya}} the ''[[Archaeopotamus]]'', likely ancestors to the genus ''Hippopotamus'' and ''[[Hexaprotodon]]'', lived in Africa and the Middle East.<ref name="Linnean"/> While the fossil record of hippos is still poorly understood, the lineages of the two modern genera, ''[[Hippopotamus (genus)|Hippopotamus]]'' and ''Choeropsis'', may have diverged as far back as {{mya|8|mya}}. The ancestral form of the pygmy hippopotamus may be the genus ''Saotherium''. ''Saotherium'' and ''Choeropsis'' are significantly more [[Basal (phylogenetics)|basal]] than ''Hippopotamus'' and ''Hexaprotodon'', and thus more closely resemble the ancestral species of hippos.<ref name="Linnean"/><ref name="Origins"/> === Extinct pygmy and dwarf hippos === Several species of small hippopotamids have also become extinct in the Mediterranean in the late [[Pleistocene]] or early [[Holocene]]. Though these species are sometimes known as "pygmy hippopotami" they are not believed to be closely related to ''C. liberiensis''. These include the [[Cretan Dwarf Hippopotamus|Cretan dwarf hippopotamus]] (''Hippopotamus creutzburgi''), the Sicilian hippopotamus (''[[Hippopotamus pentlandi]]''), the Maltese hippopotamus (''[[Hippopotamus melitensis]]'') and the [[Cyprus Dwarf Hippopotamus|Cyprus dwarf hippopotamus]] (''Hippopotamus minor'').<ref name="Taxonomy of Pleistocene">{{cite journal|last=Petronio |first=C. |year=1995 |title=Note on the taxonomy of Pleistocene hippopotamuses |journal=Ibex |volume=3 |pages=53β55 |url=http://www.mountainecology.org/IBEX3/pdf/Art_Capitolo1/note_taxonomy_pleistocene.pdf |access-date=2008-08-23 |url-status=dead |archive-url=https://web.archive.org/web/20080912012236/http://www.mountainecology.org/IBEX3/pdf/Art_Capitolo1/note_taxonomy_pleistocene.pdf |archive-date=2008-09-12 }}</ref> These species, though comparable in size to the pygmy hippopotamus, are considered dwarf hippopotamuses, rather than pygmies. They are likely descended from a full-sized species of [[Hippopotamus antiquus|European hippopotamus]], and reached their small size through the evolutionary process of [[insular dwarfism]] which is common on islands; the ancestors of pygmy hippopotami were also small and thus there was never a dwarfing process.<ref name="Taxonomy of Pleistocene"/> There were also several species of pygmy hippopotamus on the island of [[Madagascar]] (see [[Malagasy Hippopotamus|Malagasy hippopotamus]]). == Description == [[File:ZooPygmyHippo.jpg|thumb|Resting at [[Louisville Zoo]]. The skull of a pygmy hippopotamus has less pronounced [[Orbit (anatomy)|orbits]] and [[nostril]]s than a common hippopotamus.]] Pygmy hippopotamuses share the same general form as a hippopotamus. They have a [[wikt:graviportal|graviportal]] skeleton, with four stubby legs and four toes on each foot, supporting a portly frame. Yet, the pygmy is only half as tall as the hippopotamus and weighs less than 1/4 as much as its larger cousin. Adult pygmy hippos stand about {{cvt|75|β|100|cm|ft}} high at the shoulder, are {{cvt|150|β|175|cm|ft}} in length and weigh {{cvt|180|β|275|kg}}.<ref name="Macdonald, D. 2001">{{Cite book |author = Macdonald, D. |year =2001 |title =The New Encyclopedia of Mammals |publisher =Oxford University Press, Oxford |isbn =978-0198508236}}</ref> Their lifespan in captivity ranges from 30 to 55 years, though it is unlikely that they live this long in the wild.<ref name="The Hippos" /><ref name="National Zoo on pygmy hippos" /> The skin is greenish-black or brown, shading to a creamy gray on the lower body. Their skin is very similar to the common hippo's, with a thin [[Epidermis (skin)|epidermis]] over a [[dermis]] that is several centimeters thick. Pygmy hippos have the same unusual [[secretion]] as common hippos, that gives a pinkish tinge to their bodies, and is sometimes described as "blood sweat" though the secretion is neither [[sweat]] nor [[blood]]. This substance, [[hipposudoric acid]], is believed to have antiseptic and [[sunscreen]]ing properties. The skin of hippos dries out quickly and cracks, which is why both species spend so much time in water.<ref name="The Hippos" /> The skeleton of ''C. liberiensis'' is more [[wikt:gracile|gracile]] than that of the common hippopotamus, meaning their bones are proportionally thinner. The common hippo's spine is parallel with the ground; the pygmy hippo's back slopes forward, a likely [[adaptation]] to pass more easily through dense forest vegetation. Proportionally, the pygmy hippo's legs and neck are longer and its head smaller.<ref name="National Zoo on pygmy hippos" /> [[File:Zwergflusspferd - Pygmy Hippopotamus - Hexaprotodon liberiensis.jpg|thumb|Nuzzling couple at the [[Duisburg Zoo]] in Germany]] The [[Orbit (anatomy)|orbits]] and [[nostril]]s of a pygmy hippopotamus are much less pronounced, an adaptation from spending less time in deep water (where pronounced orbits and nostrils help the common hippo breathe and see). The feet of pygmy hippos are narrower, but the toes are more spread out and have less webbing, to assist in walking on the forest floor.<ref name="National Zoo on pygmy hippos" /> Despite adaptations to a more [[terrestrial animal|terrestrial]] life than the common hippopotamus, pygmy hippos are still more aquatic than all other terrestrial [[even-toed ungulate]]s. The ears and nostrils of pygmy hippos have strong muscular valves to aid submerging underwater, and the skin physiology is dependent on the availability of water.<ref name="The Hippos" /><ref name="Robinson" /> == Behavior == [[File:Pygmyhippopotamus-uenozoo2008.ogv|thumb|(video) Bathing in the [[Ueno Zoo]], [[Tokyo]], Japan]] The behavior of the pygmy hippopotamus differs from the common hippo in many ways. Much of its behavior is more similar to that of a [[tapir]], though this is an effect of [[convergent evolution]].<ref name="Robinson" /> While the common hippopotamus is gregarious, pygmy hippos live either alone or in small groups, typically a mated pair or a mother and calf. Pygmy hippos tend to ignore each other rather than fight when they meet. Field studies have estimated that male pygmy hippos range over {{convert|1.85|km2|acre|abbr=on}}, while the range of a female is {{convert|0.4|to(-)|0.6|km2|acre|-1|abbr=on}}.<ref name="The Hippos" />[[File:Pygmy hippos, Singapore Zoo.JPG|thumb|Two dive in water at [[Singapore Zoo]], [[Singapore]]|left]]Pygmy hippos spend most of the day hidden in rivers. They will rest in the same spot for several days in a row, before moving to a new spot. At least some pygmy hippos make use of dens or [[burrow]]s that form in river banks. It is unknown if the pygmy hippos help create these dens, or how common it is to use them. Though a pygmy hippopotamus has never been observed burrowing, other [[artiodactyls]], such as [[warthog]]s, are burrowers.<ref name="The Hippos" /> === Diet === Like the common hippopotamus, the pygmy hippopotamus emerges from the water at dusk to feed. It relies on game trails to travel through dense forest vegetation. It marks trails by vigorously waving its tail while defecating to further spread its feces. The pygmy hippopotamus spends about six hours a day foraging for food.<ref name="The Hippos" /> [[File:Pigmy Hippo 037.jpg|thumb|Eating a vegetable]] Pygmy hippos are [[herbivore|herbivorous]]. They do not eat aquatic vegetation to a significant extent and rarely eat grass because it is uncommon in the thick forests they inhabit. The bulk of a pygmy hippo's diet consists of [[herb]]s, [[fern]]s, [[dicotyledons|broad-leaved plants]], [[Herbaceous plant|herbaceous]] [[Shoot (botany)|shoot]]s, [[forb]]s, [[sedge]]s and [[fruit]]s that have fallen to the forest floor.<ref>{{cite web | url=https://animaldiversity.org/accounts/Hexaprotodon_liberiensis/ | title=Hexaprotodon liberiensis (Madagascan pygmy hippopotamus) | website=[[Animal Diversity Web]] }}</ref> The wide variety of plants pygmy hippos have been observed eating suggests that they will eat any plants available. This diet is of higher quality than that of the common hippopotamus.<ref name="The Hippos" /> === Reproduction === [[File:Pygmy Hippopotamus with the young.jpg|thumb|Baby stands near its parent in the [[Jihlava Zoo]], Czechia]] A study of [[breeding in the wild|breeding]] behavior in the wild has never been conducted; the artificial conditions of captivity may cause the observed behavior of pygmy hippos in zoos to differ from natural conditions. [[Sexual maturity]] for the pygmy hippopotamus occurs between three and five years of age.<ref name="Robinson" /> The youngest reported age for giving birth is a pygmy hippopotamus in the [[Zoo Basel]], Switzerland which bore a calf at three years and three months.<ref name="The Hippos" /> The [[oestrus cycle]] of a female pygmy hippopotamus lasts an average of 35.5 days, with the oestrus itself lasting between 24 and 48 hours.<ref name="Redlist" /><ref name="Distort" /> pygmy hippopotamuses consort for mating, but the duration of the relationship is unknown. In zoos they breed as [[monogamy in animals|monogamous pairs]]. [[copulation (zoology)|Copulation]] can take place on land or in the water, and a pair will mate one to four times during an oestrus period. In captivity, pygmy hippos have been conceived and born in all months of the year.<ref name="Robinson" /> The gestation period ranges from 190 to 210 days, and usually a single young is born, though twins are known to occur.<ref name="The Hippos" /> [[File:Pygmy-Hippopotamus-Lisbon-zoo.jpg|thumb|Mother and child taking a bath at Lisbon Zoo|left]] The common hippopotamus gives birth and mates only in the water, but pygmy hippopotamuses mate and give birth on both land and water. Young pygmy hippos can swim almost immediately. At birth, pygmy hippos weigh 4.5β6.2 kg (9.9β13.7 lb) with males weighing about 0.25 kg (0.55 lb) more than females. Pygmy hippos are fully [[wean]]ed between six and eight months of age; before weaning they do not accompany their mother when she leaves the water to forage, but instead hide in the water by themselves. The mother returns to the hiding spot about three times a day and calls out for the calf to suckle. Suckling occurs with the mother lying on her side.<ref name="The Hippos" /> === Temperament === Although not considered dangerous to humans and generally docile, pygmy hippopotamuses can be highly aggressive at times. Although there have been no human deaths associated with pygmy hippos, there have been several attacks - while most of these were provoked by human behaviour, several have had no apparent cause.<ref>{{Cite web |last=Γlvarez |first=Juan |date=2023-02-05 |title=Are Pygmy Hippos Aggressive? Are Dangerous as The Common? |url=https://wwwildnature.com/are-pygmy-hippos-aggressive/ |url-status=dead |archive-url=https://web.archive.org/web/20230518163411/https://wwwildnature.com/are-pygmy-hippos-aggressive/ |archive-date=2023-05-18 |access-date=2023-05-18 |website=WWWILDNATURE |language=en-US}}</ref> == Conservation == [[File:Pygmy hippopotamus pair.jpg|thumb|Pair at the [[Mount Kenya Wildlife Conservancy]]]] The greatest threat to the remaining pygmy hippopotamus population in the wild is loss of habitat. The forests in which pygmy hippos live have been subject to logging, settling and conversion to agriculture, with little efforts made to make logging sustainable. As forests shrink, the populations become more fragmented, leading to less genetic diversity in the potential mating pool.<ref name="Redlist"/> Pygmy hippos are among the species [[Environmental issues in Liberia|illegally hunted for food in Liberia]].<ref name="Anne Look">{{cite web|url=https://www.voanews.com/a/370590.html|title=Poaching in Liberia's Forests Threatens Rare Animals|work=[[Voice of America]]|first=Anne|last=Look|date=8 May 2012|access-date=5 November 2014|archive-url=https://web.archive.org/web/20160304205739/http://www.voanews.com/content/article/370590.html|archive-date=4 March 2016|url-status=live}}</ref> Their meat is said to be of excellent quality, like that of a wild boar; unlike those of the common hippo, the pygmy hippo's teeth have no value.<ref name=Robinson/> The effects of West Africa's civil strife on the pygmy hippopotamus are unknown, but unlikely to be positive.<ref name="Redlist"/> The pygmy hippopotamus can be killed by [[leopard]]s, [[Pythonidae|pythons]] and [[crocodile]]s. How often this occurs is unknown.<ref name="The Hippos"/> ''C. liberiensis'' was identified as one of the top 10 "focal species" in 2007 by the [[EDGE Species|Evolutionarily Distinct and Globally Endangered]] (EDGE) project.<ref>{{Cite news | title = Protection for 'weirdest' species | url = http://news.bbc.co.uk/2/hi/science/nature/6263331.stm | date = 2007-01-16 | access-date = 2008-08-23 | work = [[BBC]]}}</ref> Some populations inhabit protected areas, such as the [[Gola West|Gola Forest Reserve]] in Sierra Leone.<ref>{{cite web|url=http://www.visitsierraleone.org/Attractions/Nature-and-Wildlife/Gola-Forest-Reserve.html|title=Gola Forest Reserve|author=Administrator|work=Visit Sierra Leone|url-status=dead|archive-url=https://web.archive.org/web/20100308113317/http://www.visitsierraleone.org/Attractions/Nature-and-Wildlife/Gola-Forest-Reserve.html|archive-date=2010-03-08}}</ref> [[Basel Zoo]] in Switzerland holds the international [[studbook]] and coordinates the entire captive pygmy hippopotamus population that freely breeds in zoos around the world. Between 1970 and 1991 the population of pygmy hippos born in captivity more than doubled. The survival of the species in zoos is more certain than the survival of the species in the wild.<ref name=Action/><ref name="National Zoo on pygmy hippos">{{Cite web | url = http://nationalzoo.si.edu/Animals/AsianElephants/factpygmyhippo.cfm | title = Pygmy Hippo fact sheet | publisher = National Zoological Park | access-date = 2008-08-23|archive-url=https://web.archive.org/web/20080825231829/http://nationalzoo.si.edu/animals/asianelephants/factpygmyhippo.cfm|archive-date=2008-08-25}}</ref> In captivity, the pygmy hippopotamus lives from 42 to 55 years, longer than in the wild.<ref name="The Hippos">{{Cite book| title = The Hippos | author = Eltringham, S. Keith | isbn=978-0-85661-131-5| year = 1999| publisher = Academic Press| location = London}}</ref> Since 1919, only 41 percent of pygmy hippos born in zoos have been male.<ref name=Distort>{{Cite journal | journal = [[Journal of Mammalogy]] | volume = 83 | pages = 674β681 | year = 2002 | title = Distorted Sex Ratio at Birth in the Captive Pygmy Hippopotamus, Hexaprotodon Liberiensis | author = Zschokke, Samuel | doi = 10.1644/1545-1542(2002)083<0674:DSRABI>2.0.CO;2 | issue = 3| doi-access = free }}</ref> == History and folklore == [[File:Pygmy hippopotamus hungry.jpg|thumb|Pair at the Mount Kenya Wildlife Conservancy]] While the common hippopotamus has been known to Europeans since [[classical antiquity]], the pygmy hippopotamus was unknown outside its range in West Africa until the 19th century. Due to their nocturnal, forested existence, they were poorly known within their range as well. In Liberia the animal was traditionally known as a ''water cow''.<ref name=Robinson/> Early field reports of the animal misidentified it as a [[wild hog]]. Several skulls of the species were sent to the American natural scientist [[Samuel G. Morton]], during his residency in [[Monrovia]], [[Liberia]]. Morton first described the species in 1843. The first complete specimens were collected as part of a comprehensive investigation of Liberian fauna in the 1870s and 1880s by Dr. [[Johann BΓΌttikofer]]. The specimens were taken to the [[Natural History Museum, Leiden|Natural History Museum]] in [[Leiden]], The [[Netherlands]].<ref name=Robinson/> The first pygmy hippopotamus was brought to Europe in 1873 after being captured in Sierra Leone by a member of the British Colonial Service but died shortly after arrival. Pygmy hippos were successfully established in European zoos in 1911. They were first shipped to [[Germany]] and then to the [[Bronx Zoo]] in [[New York City]] where they also thrived.<ref name="The Hippos"/><ref name=Robinson>Robinson, Phillip T. [http://moray.ml.duke.edu/projects/hippos/Pygmy_Text.doc River Horses and Water Cows] {{webarchive|url=https://web.archive.org/web/20090326091218/http://moray.ml.duke.edu/projects/hippos/Pygmy_Text.doc |date=2009-03-26 }}. ''[http://moray.ml.duke.edu/projects/hippos/index.html Hippo Specialist Group of the World Conservation Union] {{webarchive|url=https://web.archive.org/web/20070717150523/http://moray.ml.duke.edu/projects/hippos/index.html |date=2007-07-17 }}''. Retrieved on 2007-07-30.</ref> In 1927, [[Harvey Firestone]] of [[Firestone Tire and Rubber Company|Firestone Tires]] presented [[Billy (pygmy hippo)|Billy the pygmy hippo]] to U.S. President [[Calvin Coolidge]]. Coolidge donated Billy to the [[National Zoological Park (United States)|National Zoo in Washington, D.C.]] According to the zoo, Billy is a common ancestor to most pygmy hippos in U.S. zoos today.<ref name="National Zoo on pygmy hippos" /><ref name=Tale>{{Cite journal | journal = [[Quaternary International]] | volume = 117 | issue = 1 | year = 2004 | pages = 119β123 | title = The hippo's tale: how the anatomy and physiology of Late Neogene Hexaprotodon shed light on Late Neogene environmental change | author = Jablonski, Nina G. | doi = 10.1016/S1040-6182(03)00121-6 | bibcode = 2004QuInt.117..119J }}</ref> [[Moo Deng]] is a pygmy hippopotamus living in [[Khao Kheow Open Zoo]], in Thailand, who gained notability in September 2024 as a popular [[Internet meme]] after images of her went viral online.<ref>{{Cite web |date=September 13, 2024 |title=Moo Deng: Thailand zoo's celebrity baby pygmy hippo |url=https://www.bbc.com/news/articles/cy848292dr4o |access-date=2024-09-18 |website=[[BBC]] |language=en-GB}}</ref> Because of the popularity of the hippo, whose name translates to "bouncy pork", the zoo saw a boosted attendance. It has been reported that some visitors to the zoo threw water and other objects at the baby hippo to get her to react.<ref> {{Cite web |date=2024-09-29 |title=Moo Deng: Why is internet obsessed with the viral baby hippo? |url=https://www.independent.co.uk/asia/southeast-asia/moo-deng-livestream-baby-pygmy-hippo-viral-memes-b2620832.html |access-date=2024-10-01 |website=The Independent |language=en}}</ref> Several folktales have been collected about the pygmy hippopotamus. One tale says that pygmy hippos carry a shining diamond in their mouths to help travel through thick forests at night; by day the pygmy hippopotamus has a secret hiding place for the diamond, but if a hunter catches a pygmy hippopotamus at night the diamond can be taken. Villagers sometimes believed that baby pygmy hippos do not nurse but rather lick secretions off the skin of the mother.<ref name=Robinson/> == See also == *[[List of individual hippos]] == References == {{Reflist}} ==External links== {{Commons|Hexaprotodon liberiensis}} * [https://web.archive.org/web/20141027172940/http://www.arkive.org/pygmy-hippopotamus/choeropsis-liberiensis/videos.html Videos of Pygmy Hippos] at [[Arkive|Arkive.org]] * [https://www.bbc.co.uk/news/science-environment-16250716 Pygmy hippo caught on camera in Liberia] (video), [[BBC News]] 2011-12-19 * [http://news.bbc.co.uk/2/hi/science/nature/7286860.stm Rare pygmy hippos caught on film], [[BBC News]] 2008-03-10 ** [https://www.edgeofexistence.org/blog/camera-trap-results/ Camera trap results], [[Sapo National Park]], [[Liberia]], [[Zoological Society of London]] ([[EDGE of Existence Programme]]). 10 March 2008. ''First reports showing Pygmy Hippos in wild, surviving [[Second Liberian Civil War|Liberian Civil War]].'' ** [https://web.archive.org/web/20080314053159/http://zsl.org/field-conservation/news/pygmy-hippos,437,NS.html Pygmy hippos survive two civil wars], [[Zoological Society of London]] Press Release, 10 March 2008. * EDGE of Existence [https://www.edgeofexistence.org/species/pygmy-hippopotamus/ "(Pygmy hippo)"], Saving the World's most Evolutionarily Distinct and Globally Endangered (EDGE) species {{Artiodactyla|C.}} {{Taxonbar|from=Q202241|from2=Q22110899|from3=Q20908132|from4=Q20908133}} {{Featured article}} [[Category:Hippopotamuses|pygmy hippopotamus]] [[Category:EDGE species]] [[Category:Mammals of West Africa]] [[Category:Fauna of Rivers State]] [[Category:Endangered fauna of Africa]] [[Category:Semiaquatic mammals]] [[Category:Articles containing video clips]] [[Category:Mammals described in 1849|pygmy hippopotamus]]
Edit summary
(Briefly describe your changes)
By publishing changes, you agree to the
Terms of Use
, and you irrevocably agree to release your contribution under the
CC BY-SA 4.0 License
and the
GFDL
. You agree that a hyperlink or URL is sufficient attribution under the Creative Commons license.
Cancel
Editing help
(opens in new window)
Pages transcluded onto the current version of this page
(
help
)
:
Template:Artiodactyla
(
edit
)
Template:BioRef
(
edit
)
Template:Cite book
(
edit
)
Template:Cite journal
(
edit
)
Template:Cite news
(
edit
)
Template:Cite web
(
edit
)
Template:Commons
(
edit
)
Template:Convert
(
edit
)
Template:Cvt
(
edit
)
Template:Featured article
(
edit
)
Template:Ill
(
edit
)
Template:Main
(
edit
)
Template:Mya
(
edit
)
Template:Pp-move-indef
(
edit
)
Template:Reflist
(
edit
)
Template:Short description
(
edit
)
Template:Sister project
(
edit
)
Template:Speciesbox
(
edit
)
Template:Taxonbar
(
edit
)
Template:Webarchive
(
edit
)