Crab-eating fox
| Crab-eating fox[1] | |
|---|---|
| |
| Cerdocyon thousfromColombia | |
Scientific classification
| |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Order: | Carnivora |
| Family: | Canidae |
| Tribe: | Canini |
| Subtribe: | Cerdocyonina |
| Genus: | Cerdocyon C. E. H. Smith,1839 |
| Species: | C. thous
|
| Binomial name | |
| Cerdocyon thous (Linnaeus,1766)
| |
| |
| Crab-eating fox range | |
| Synonyms | |
|
Canis thousLinnaeus, 1766 | |
Thecrab-eating fox(Cerdocyon thous), also known as theforest fox,wood fox,bushdog(not to be confused with thebush dog) ormaikong,is anextantspecies of medium-sizedcanidendemic to the central part ofSouth Americasince at least thePleistoceneepoch.[1][2][4]LikeSouth American foxes,which are in thegenusLycalopex,it is not closely related to true foxes.Cerdocyoncomes from theGreekwordskerdo(meaning fox) andkyon(dog) referring to the dog- and fox-like characteristics of this animal.[5]
Taxonomy and evolution
[edit]The crab-eating fox was originally described asCanis thousby Linnaeus (1766), and first placed in its current genusCerdocyonby Hamilton-Smith in 1839.[4]
Cerdocyonina is atribewhich appeared around 6.0 million years ago (Mya) inNorth AmericaasFerrucyon aviusbecoming extinct by around 1.4–1.3 Mya. living about4.7million years.This genus has persisted in South America from an undetermined time, possibly around 3.1 Mya, and continues to the present in the same or a similar form to the crab-eating fox.[6]
As one of the species of the tribeCanini,it is related to the genusCanis.The crab-eating fox's nearest living relative, as theorized at present, is theshort-eared dog.This relationship, however, has yet to be supported by mitochondrial investigations. Two subgenera (AtelocynusandSpeothos) were long ago included inCerdocyon.
Cerdocyon thous,C. aviusand other species of the genusCerdocyonunderwent radiational evolution on the South American continent.[7]All close relatives of the crab-eating fox (Cerdocyon thous) are extinct. It is the only living representative at present of the genusCerdocyon.
Description
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The crab-eating fox is predominantly greyish-brown, with areas of red on the face and legs, and black-tipped ears and tail. It has short, strong legs and its tail is long and bushy. The head and body length averages 64.3 centimetres (25.3 in), and the average tail length is 28.5 centimetres (11.2 in).[8]It can weigh between 10 and 17 pounds (4.5 and 7.7 kg).[9][10]
The coat is short and thick. Coloration varies from grey to brown, to yellowish, to pale, to dark grey. There is a black streak along the back legs, with a black stripe along the spine. On muzzle, ears and paws there is more-reddish fur. The tail, legs and ear tips are black. The ears are wide and round. The torso is somewhat narrow; legs are short but strong. The dense hairy tail stays upright when they are excited. There is significant variation in color between population, from very dark to light grey-yellow.[4]
Genetically, there are 74diploidchromosomes (36 pairs).
Habitat
[edit]The crab-eating fox is a canid that ranges insavannas;woodlands;subtropicalforests; prickly, shrubby thickets; and tropical savannas such as thecaatinga,plains,andcampo,fromColombiaand southernVenezuelain the north toParaguay,Uruguayand northernArgentinaat the southernmost reaches of its range.[11]The crab-eating fox has also been sighted inPanamasince the 1990s.[12]
Its habitat also includes wooded riverbanks such asriparian forest.In the rainy season, their range moves uphill, whilst in drier times they move to lower ground.[13]Their habitat covers all environments exceptrainforests,high mountains, and open grassy savannas. In some regions of their range, they are threatened with extirpation.
Behaviour and ecology
[edit]The crab-eating fox createsmonogamicteams for hunting; groups of several monogamic pairs may form during the reproductive season. Population density estimates vary between one individual per 4 km2in Venezuela to 0.0003 individuals/km2in Argentinian wetlands.[8][14][15]Territorialismwas noticed during the dry season; during rainy seasons, when there is more food, they pay less attention to territory.[13]Hideouts and dens often are found in bushes and in thick grass, and there are typically multiple entrance holes per den. Despite being capable of tunneling, they prefer to take over other animals' burrows. Several characteristic sounds are made by the crab-eating fox such as barking, whirring andhowling,which occur often when pairs lose contact with one another.
The crab eating fox is nocturnal, with peaks of activity in the middle of the night and the early morning.[16]
Reproduction
[edit]
The foxes reach sexual maturity within 9–10 months year. Adult females gives birth to one or two litters per year, depending on the climate and the availability of food.[15]The reproductive period most often begins in November or December, and again in July. The birth of offspring follows after an approximately 56-day gestation,[17]typically in January, February or sometimes March,[13]then again from September to October. If giving birth to one litter, they typically give birth in the early spring. Thebreeding pairis monogamous and raises the pups together, which are weaned at around three months old and become independent of their parents around 5–8 months old.[15]
Diet
[edit]The crab-eating fox searches for crabs on muddyfloodplainsduring the wet season, giving this animal its common name. It is an opportunist and an omnivore, preferring insects or meat from rodents and birds when available. Other foods readily consumed includeother crustaceans,tortoises, turtle eggs,bird eggs,insects, lizards, fruit, andcarrion.Their diet is varied and has been found to differ by different researchers, suggesting opportunistic feeding and geographical variation. During thewet season,the diet contains more crustaceans, while during thedry seasonit contains more insects.[8]The crab-eating fox contributes to the control ofrodentsandharmful insects.
Conservation
[edit]The Convention on International Trade inEndangeredSpecies of Wild Fauna and Flora (CITES) lists the fox as not threatened by extinction.[18]TheIUCNlists the crab-eating fox as being of "Least Concern".[2]There are no precise estimates of the population size, but it is common within its range and the population is stable.[4]
It is considered a threat to livestock by farmers, which leads to illegal hunting in some countries. The primary threat to the fox is disease from unvaccinated dogs.[14]
Subspecies
[edit]The crab-eating fox has five recognizedsubspecies,[1]differing in sizes and coloring of fur.[19]
- C. t. thous,Venezuela,Guyana,Suriname,French GuianaNorthBrazil.
- C. t. azarae,NorthBrazil.
- C. t. entrerianus,Brazil,Bolivia.Uruguay,ParaguayandArgentina.
- C. t. aquilus,northVenezuelaandColombia.
- C. t. germanus,Bogotáregion (Colombia).
References
[edit]- ^abcWozencraft, W. C.(2005)."Order Carnivora".InWilson, D. E.;Reeder, D. M. (eds.).Mammal Species of the World: A Taxonomic and Geographic Reference(3rd ed.). Johns Hopkins University Press. p. 578.ISBN978-0-8018-8221-0.OCLC62265494.
- ^abcLucherini, M. (2015)."Cerdocyon thous".IUCN Red List of Threatened Species.2015:e.T4248A81266293.doi:10.2305/IUCN.UK.2015-4.RLTS.T4248A81266293.en.Retrieved13 November2021.
- ^"Appendices | CITES".cites.org.Retrieved2022-01-14.
- ^abcdCanids: foxes, wolves, jackals, and dogs: status survey and conservation action plan(PDF).Claudio Sillero-Zubiri, Michael Hoffmann, David W. Macdonald, IUCN/SSC Canid Specialist Group, IUCN--The World Conservation Union. Gland, Switzerland. 2004.ISBN2-8317-0786-2.OCLC57570754.Archived fromthe original(PDF)on September 3, 2022.
{{cite book}}:CS1 maint: location missing publisher (link) CS1 maint: others (link) - ^Braun, Janet K.; Mares, Michael A. (1995)."The Mammals of Argentina: An Etymology"(PDF).Mastozoología Neotropical.2(2). SAREM: 173–206.ISSN0327-9383.Archived fromthe original(PDF)on October 18, 2016.
- ^Tetford, Richard H.; Wang, Xiaoming; Taylor, Beryl E. (September 2009)."Phylogenetic Systematics of the North American Fossil Caninae (Carnivora: Canidae)".Bulletin of the American Museum of Natural History.325:1–218.doi:10.1206/574.1.S2CID83594819.
- ^De Lavigne, Guillaume. Free Ranging Dogs-Stray, Feral or Wild?. Lulu Press, Inc, 2015.
- ^abcAnnalisa Berta; Cerdocyon thous, Mammalian Species, Issue 186, 23 November 1982, Pages 1–4,https://doi.org/10.2307/3503974
- ^Amanda Hover."Cerdocyon thous (crab-eating fox)".Animal Diversity Web.Retrieved2022-09-18.
- ^Yahnke CJ, Johnson WE, Geffen E, Smith D, Hertel F, Roy MS, Bonacic CF, Fuller TK, Van Valkenburgh V, Wayne RK (1996) Darwin’s fox: a distinct endangered species in a vanishing habitat. Conserv Biol 10:366–375
- ^J.F. Eisenberg, K.H. Redford Mammals of the Neotropics – The Central Neotropics, vol. 3, University of Chicago Press, Chicago (1999)
- ^Tejera-N, VH; Araúz-G., V. León, A. R. Rodríguez, P. González, S. Bermúdez & R. Moreno. 1999. Primer registro del zorro cangrejero Cerdocyon thous (Carnivora: Canidae), para Panamá. Scientia 14: 103-107
- ^abcNowak, Ronald M. (2005).Walker's Carnivores of the World.Baltimore: Johns Hopkins Press.ISBN0-8018-8032-7
- ^ab"Crab-eating fox | Canids".canids.org.Retrieved2022-09-18.
- ^abcFaria-Corrêa, Mariana; Balbueno, Rodrigo A.; Vieira, Emerson M.; de Freitas, Thales R. O. (2009-05-01)."Activity, habitat use, density, and reproductive biology of the crab-eating fox (Cerdocyon thous) and comparison with the pampas fox (Lycalopex gymnocercus) in a Restinga area in the southern Brazilian Atlantic Forest".Mammalian Biology.74(3): 220–229.doi:10.1016/j.mambio.2008.12.005.ISSN1618-1476.
- ^Monteiro-Alves, Priscila Stéfani; Helmer, Débora Molino; Ferreguetti, Atilla Colombo; Pereira-Ribeiro, Juliane; Rocha, Carlos Frederico Duarte; Bergallo, Helena Godoy (2019-06-27)."Occupancy, detectability, and density of crab-eating fox (Cerdocyon thous) in two protected areas of restinga habitats in Brazil".Canadian Journal of Zoology.97(10): 952–959.doi:10.1139/cjz-2018-0322.S2CID198245440.
- ^Brady, Charles A. "Reproduction, growth and parental care in crab-eating foxes Cerdocyon thous at the National Zoological Park, Washington."International zoo yearbook (1978).
- ^Hutton, Jon, and Barnabas Dickson, eds. Endangered species, threatened convention: the past, present and future of CITES, the Convention on International Trade in Endangered Species of Wild Fauna and Flora. London: Earthscan, 2000.
- ^BISBAL, Francisco J. "A taxonomic study of the crab-eating fox, Cerdocyon thous, in Venezuela." Mammalia 52.2 (1988): 181-186.
External links
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