Darwin fox

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Darwin fox
Darwin fox

Darwin fox

Systematics
Order : Predators (Carnivora)
Subordination : Canine (Caniformia)
Family : Dogs (Canidae)
Tribe : Real dogs (Canini)
Genre : Lycalopex
Type : Darwin fox
Scientific name
Lycalopex fulvipes
( Martin , 1837)

The Darwin fox ( Lycalopex fulvipes , Syn . : Pseudalopex fulvipes ) is a small, endangered species of real dogs . It was discovered in 1834 by the famous naturalist Charles Darwin on a side island of the Chiloé archipelago in Chile . For a long time it was considered to be the chilotic island form of the Argentine battle fox ( Lycalopex griseus ), but with the discovery of a small population on the South American mainland in the Nahuelbuta National Park in 1990 and subsequent genetic analyzes it became clear that the species status is justified.

discovery

On December 6, 1834, Charles Darwin killed a fox with his geologist's hammer during his voyage with the Beagle on the island of San Pedro south of Quellón on Chiloé . He described it as rare, typical for the island of Chiloé and of a species that has not yet been described. It was initially referred to as ( Dusicyon fulvipes ), but was later assigned to the Argentine battle fox , as there were no basic morphological characteristics that clearly distinguish it from it distinguished. Its presence on an island seemed to confirm the assumption that it is just an island variant of the Argentine gray fox. When Darwin foxes were discovered in the Nahuelbuta National Park 600 kilometers further north on the South American mainland in the 1960s, the subspecies status was again called into question. Genetic analyzes of the mitochondria - DNA now unequivocally showed that the Darwin fox is an independent species and that Darwin was ultimately right.

features

The Darwin fox has dark brown fur with reddish areas on the head and face. It does not mate with other Lycalopex species and is smaller and darker in color than these. Its legs are also shorter than those of mainland species. At only 2–4 kilograms, it is much smaller than an Argentine battle fox ( Lycalopex griseus ), which weighs 5–10 kilograms.

distribution

In the late Pleistocene , the island of Chiloé was connected to the South American continent by a land bridge. Thick forests covered the island and adjacent parts of the south of South America. This was inhabited by the Darwin fox, which had split off early on from a common ancestor of the Argentine battle fox ( Lycalopex griseus ) and the Andean jackal ( Lycalopex culpaeus ). About 15,000 years ago, this land bridge sank in the sea as the sea level rose due to the melting of the glacial masses of the Ice Age. This created two separate populations of the Darwin's fox, one on the island and the other on the mainland. You can still find them there today, but the distribution area on the mainland has been severely melted down by climatic causes and human activities and is now limited to a small area around the Nahuelbuta National Park.

Way of life

The Darwin fox is apparently a typical forest animal that inhabits the southern, temperate rainforests. It is mainly active at dusk and before sunrise.

Diet and hunting behavior

The Darwin fox is an omnivore that easily adapts to the prevailing conditions. Its diet consists mainly of insects and smaller mammals ( rodents , hares and pudus ), birds, amphibians and reptiles. In some months, the proportion of fruits and berries in the diet increases to 20 percent. Plant seeds are also important for the mainland population. In rare cases, the Darwin fox will eat carrion from medium-sized pets. On Chiloé, each fox usually hunts alone, although several animals have been spotted on a carcass.

Social behavior and reproduction

Studies with camera traps suggest that Darwin foxes on Chiloé live lonely outside of the mating season. Each animal has an area of ​​around 1.5 km² which it shares with several other males and females. For mating, the male lives with a female for a few days and then leaves it again, so that young animals of the island population are only looked after by their mothers. Mating and young animal rearing take place between October and January. Before giving birth, the female looks for a natural hiding place such as crevices in the rock.

On the mainland, the monogamous pairs last longer and here the male guards the young when the female is looking for food. Usually two to three young animals are born. Suckling females could be seen in the national park between October and February. Examples equipped with radio transmitters were about seven years old.

Duration

It is estimated that there are only about 250 animals on Chiloé and fewer than 70 on the mainland. The species is classified as critically endangered by the IUCN . The destruction of the forests around the national park and dogs that bring epidemics and attack the foxes are the main causes of the low population densities.

Individual evidence

  1. Rodrigo G. Medel et al: Discovery of a continental population of the rare Darwin Fox, 'Dusicyon fulvipes' (Martin, 1839) in Chile. In: Biological Conservation. 51, 1990, pp. 71-77
  2. a b Christopher J. Yahnke and others: Darwin's Fox: A Distinct Endangered Species in a Vanishing Habitat. In: Conservation Biology. 10, 1996, pp. 366-375
  3. ^ C. Villagrán: Late Quaternary vegetation of Southern Isla Grande de Chiloë, Chile. In: Quaternary Research. 29, 1988, pp. 294-306
  4. Lycalopex fulvipes in the endangered Red List species the IUCN 2008 Posted by: J. E. Jiménez, M. Lucherini, A. J. Novaro, 2008. Accessed on 13 May, 2009.
  5. ^ A b c Claudio Sillero-Zubiri, Michael Hoffmann, David Whyte Macdonald: Canids: Foxes, Wolves, Jackals and Dogs. (PDF; 9.9 MB) IUCN , 2004, pp. 50–55 , accessed on February 8, 2012 .

literature

  • Ronald M. Nowak: Walker's Mammals of the World. 6th edition. Johns Hopkins University Press, Baltimore 1999, ISBN 0-8018-5789-9 .
  • David Macdonald: The Great Encyclopedia of Mammals. Könemann in the Tandem-Verlags-GmbH, Königswinter 2004, ISBN 3-8331-1006-6 .

Web links

Commons : Pseudalopex fulvipes  - collection of images, videos and audio files