Darwin's fox or Darwin's zorro (''Lycalopex fulvipes'') is an

endangered An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching and inva ...

canid from the genus ''

Lycalopex The South American foxes (''Lycalopex''), commonly called ''raposa'' in Portuguese, or ''zorro'' in Spanish, are a genus from South America of the subfamily Caninae. Despite their name, they are not true foxes, but are a unique canid genus more ...

''. It is also known as the ''zorro chilote'' or ''zorro de Darwin'' in Spanish and lives on

Nahuelbuta National Park Nahuelbuta National Park () is one of the few parks located in La Araucanía Region of Chile's Coastal Mountain Range. It sits atop the highest part of the Cordillera de Nahuelbuta. Created in 1939, it consists of 6,832 hectares situated just 16 ...

, the

Cordillera de Oncol The Cordillera de Oncol (sometimes called Valdivian Coast Range) is a mountain range, located along the Pacific Ocean, Pacific coast in southern Chile. It is part of the Chilean Coast Range System (''Cordillera de la Costa''). It was named for the ...

Cordillera Pelada Cordillera Pelada (Spanish for Bald Range or Barren Range) is a mountain range in southern Los Ríos Region, southern Chile. It is located along the Pacific coast and forms part of the larger Chilean Coast Range. It got its name ''pelada'' from the ...

in mainland

Chile Chile, officially the Republic of Chile, is a country in the western part of South America. It is the southernmost country in the world, and the closest to Antarctica, occupying a long and narrow strip of land between the Andes to the east a ...

and

Chiloé Island Chiloé Island ( es, Isla de Chiloé, , ) also known as Greater Island of Chiloé (''Isla Grande de Chiloé''), is the largest island of the Chiloé Archipelago off the west coast of Chile, in the Pacific Ocean. The island is located in southern ...

.Farías, A. A., M. A. Sepúlveda, E. A. Silva-Rodríguez, A. Eguren, D. González, N. I. Jordán, E. Ovando, P. Stowhas. 2014. A new population of Darwin's fox (''Lycalopex fulvipes'') in the Valdivian Coastal Range. ''

Revista Chilena de Historia Natural The ''Revista Chilena de Historia Natural'' is a bilingual open access scientific journal published by the Sociedad de Biología de Chile covering research in many areas of biology Biology is the scientific study of life. It is a natura ...

'' 87:3. This small, dark canine weighs , has a head-and-body length of and a tail that is . Darwin's fox displays no key differences between male and female other than the fact that the male has a broader muzzle. Males display no territorial behavior and aren't aggressive towards other males roaming around their territory. Darwin's fox was first collected from San Pedro Island off the coast of Chile by the naturalist

Charles Darwin Charles Robert Darwin ( ; 12 February 1809 – 19 April 1882) was an English naturalist, geologist, and biologist, widely known for his contributions to evolutionary biology. His proposition that all species of life have descended fr ...

in 1834. It was long held that Darwin's fox was a subspecies of the

South American gray fox The South American gray fox (''Lycalopex griseus''), also known as the Patagonian fox, the chilla or the gray zorro, is a species of ''Lycalopex'', the "false" foxes. It is endemic to the southern part of South America. Description The South A ...

(''L. griseus''); however, the discovery of a small population of Darwin's fox on the mainland in

in 1990Medel, R. G. et al. 1990. Discovery of a continental population of the rare Darwin fox, ''Dusicyon fulvipes'' (Martin, 1839) in Chile. ''Biological Conservation'' 51:71–77 and subsequent genetic analysis has clarified the fox's status as a unique species.Yahnke, C.J. et al. 1996. "Darwin's Fox: A Distinct Endangered Species in a Vanishing Habitat". ''Conservation Biology'' 10:366–375 In 2012 and 2013 the presence of the Darwin's fox at

Oncol Park Oncol Park (Spanish: ''Parque Oncol'') is a natural reserve located from the city of Valdivia, Chile. The park has an area of of which most lies on Cerro Oncol (715 m), the highest peak of the Valdivian Coast Range, but is only from the coast. ...

Alerce Costero National Park Alerce Costero National Park ( es, Parque Nacional Alerce Costero, ) is a protected wild area in the Cordillera Pelada about from Valdivia and from La Unión. ''Fitzroya'' trees grow inside the protected area and give the area its name, with ' ...

and the

Valdivian Coastal Reserve Valdivian Coastal Reserve is a natural reserve located in the Cordillera Pelada, in Los Ríos Region of Chile, near Corral. History In 2003, the WWF Chile program, The Nature Conservancy (TNC) and other local organizations acquired a nearly 60, ...

was confirmed through camera trapping.

Taxonomy and evolution

''Lycalopex'' is a

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the southe ...

n genus of canine distantly related to wolves and is technically not a

fox Foxes are small to medium-sized, omnivorous mammals belonging to several genera of the family Canidae. They have a flattened skull, upright, triangular ears, a pointed, slightly upturned snout, and a long bushy tail (or ''brush''). Twelve sp ...

. When Charles Darwin collected a specimen from San Pedro Island in Chiloé Archipelago in December 1834 during the ''Beagle'' survey expedition, he observed that this "fox (of Chiloe, a rare animal) sat on the point & was so absorbed in watching urvey work that he allowed me to walk behind him & actually kill him with my geological hammer". Keynes, R. D. ed. 2001. ''Charles Darwin's Beagle diary''. Cambridge: Cambridge University Press. pp
272–273
/ref> In the 1839 publication of his '' Journal and Remarks'', Darwin said "This fox, more curious or more scientific, but less wise, than the generality of his brethren, is now mounted in the museum of the Zoological Society." He said it was "an undescribed species",Darwin, C. R. 1839. ''Narrative of the surveying voyages of His Majesty's Ships Adventure and Beagle between the years 1826 and 1836, Journal and Remarks 1832–1836''. London: Henry Colburn. p
341
/ref> indicating that it was distinct from the species ( ''L. culpaeus'' and ''L. griseus'') that occur on the mainland. Later, Darwin's fox was classified as a subspecies (''Lycalopex griseus fulvipes'') of the latter. Darwin's fox does not

interbreed In biology, a hybrid is the offspring resulting from combining the qualities of two organisms of different breeds, varieties, species or genera through sexual reproduction. Hybrids are not always intermediates between their parents (such as in ...

with the other ''Lycalopex'' species, only lives in forests, and is smaller and darker-colored than the other species. In 1990 a small population of Darwin's fox was found on the mainland in the forested Nahuelbuta National Park, indicating that the fox was not endemic to the island. According to Yahnke et al., in their 1996 article published in the Journal of the Society for Conservation Biology, analysis of mitochondrial DNA of Darwin's fox and the gray fox showed two patterns, indicating Darwin's fox was a new species, closely related to the

Sechuran fox The Sechuran fox (''Lycalopex sechurae''), also called the Peruvian desert fox or the Sechuran zorro, is a small South American species of canid closely related to other South American "false" foxes or zorro. It gets its name for being found in ...

. Also according to Yahnke (1995; et al.1996) the present restricted range is a relic of a much wider former range. Zoologists noted the distinctiveness in the ecological niche, appearance, and behavior of this species. Darwin's fox is differentiated from the gray fox in being darker; having shorter legs; a broader, shorter skull; smaller auditory bullae; a more robust dentition; and a different jaw shape and style of premolar occlusion. In the late

Pleistocene The Pleistocene ( , often referred to as the ''Ice age'') is the geological Epoch (geology), epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fina ...

, Chiloé Island was connected to mainland Chile by a land bridge. The land bridge was severed about 15,000 years ago when the sea level rose following the last glaciation. Villagrán, C. 1988. Late Quaternary vegetation of Southern Isla Grande de Chiloë, Chile. ''Quaternary Research'' 29: 294–306 This created two isolated populations of Darwin's fox.

Diet

Darwin's fox has a vast diet. In dense forests, where it exists, the foxes hunt for mammals,

reptile Reptiles, as most commonly defined are the animals in the class Reptilia ( ), a paraphyletic grouping comprising all sauropsids except birds. Living reptiles comprise turtles, crocodilians, squamates (lizards and snakes) and rhynchocephalians ( ...

beetle Beetles are insects that form the order Coleoptera (), in the superorder Endopterygota. Their front pair of wings are hardened into wing-cases, elytra, distinguishing them from most other insects. The Coleoptera, with about 400,000 describ ...

s, and

invertebrate Invertebrates are a paraphyletic group of animals that neither possess nor develop a vertebral column (commonly known as a ''backbone'' or ''spine''), derived from the notochord. This is a grouping including all animals apart from the chordate ...

s. Sometimes it selects

fruit In botany, a fruit is the seed-bearing structure in flowering plants that is formed from the ovary after flowering. Fruits are the means by which flowering plants (also known as angiosperms) disseminate their seeds. Edible fruits in particu ...

s and

berries A berry is a small, pulpy, and often edible fruit. Typically, berries are juicy, rounded, brightly colored, sweet, sour or tart, and do not have a stone or pit, although many pips or seeds may be present. Common examples are strawberries, raspb ...

Bird Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweigh ...

s and

amphibian Amphibians are tetrapod, four-limbed and ectothermic vertebrates of the Class (biology), class Amphibia. All living amphibians belong to the group Lissamphibia. They inhabit a wide variety of habitats, with most species living within terres ...

s to a lesser degree are also consumed. It sometimes eats carrion, but it mostly eats live animals and fruit. This makes it mostly an omnivore, sometimes a scavenger.

Ecology

Darwin's fox is generally believed to be a forest obligate species found only in southern temperate rainforests. They only occur in areas of primary forest on Chiloé and on the mainland. They are most active at twilight and before sunrise. In contrast to other ''Lycalopex'' species, Darwin's fox prefers open spaces. The population of Chiloé has about 200 individuals, and Nahuelbuta on the mainland contains about 50 individuals. The total population size is about 250 mature individuals with at least 90% of the population occurring in one subspopulation (Chiloé Island). Although the species is protected in Nahuelbuta National Park, substantial mortality sources exist when foxes move to lower, unprotected private areas in search of milder conditions during the winter. The population was considered as critically endangered because its main population occurred in one island and their habitat was declining due to human impact.

Conservation status

The species was previously classified as Critically Endangered by the

IUCN The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...

, but in 2016 was downlisted to

Endangered An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching and inva ...

, as its area occurrences is apparently substantially larger than originally believed. Current estimates of the total population are still low, with an estimated minimum 227 individuals on the mainland and 412 on Chiloé Island. Fragmentation of forest adjacent to the national park and on the island is a concern for their conservation, and feral dogs may pose the greatest threat to their survival by spreading disease or directly attacking. Persecution by people who think that the foxes attack domestic fowls, though they pose little threat, is also a potential problem.

Diseases

The species is often plagued by ''

Mycoplasma haemocanis ''Mycoplasma'' is a genus of bacteria that, like the other members of the class ''Mollicutes'', lack a cell wall around their cell membranes. Peptidoglycan (murein) is absent. This characteristic makes them naturally resistant to antibiotics ...

''. The already endangered fox is prone to this

infection An infection is the invasion of tissues by pathogens, their multiplication, and the reaction of host tissues to the infectious agent and the toxins they produce. An infectious disease, also known as a transmissible disease or communicable dise ...

because the infection's bacteria attach themselves to surface red blood cells of many mammals, and although the species is believed to be no major threat to human life it can spread to humans, dogs, cats, and other wildlife species. The bacteria also seem to spike when located close to any major habitat inhabited by humans as well as where there is a large population of wild dogs present near the species. Researchers are testing RNA subunits of RNase P gene and out of 10 foxes, nine were infected. Even though they are considered "sick", they have no external symptoms (Cabello, 2013). Studies show that many foxes risk of catching the deadly bacteria inclines as they age leaving many older foxes vulnerable. Although the disease is prevalent in this specie little to nothing is known about this disease.

References

{{Taxonbar, from=Q631167

Darwin's fox Darwin's fox or Darwin's zorro (''Lycalopex fulvipes'') is an endangered canid from the genus ''Lycalopex''. It is also known as the ''zorro chilote'' or ''zorro de Darwin'' in Spanish and lives on Nahuelbuta National Park, the Cordillera de O ...

Mammals of Chile Mammals of Patagonia Chiloé Archipelago Endangered animals Endangered biota of South America

Endemic fauna of Chile