Scoop dog
| Scoop dog | ||||||||||||
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Scoop dog ( Otocyon megalotis ) |
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| Systematics | ||||||||||||
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| Scientific name of the genus | ||||||||||||
| Otocyon | ||||||||||||
| Müller , 1836 | ||||||||||||
| Scientific name of the species | ||||||||||||
| Otocyon megalotis | ||||||||||||
| ( Desmarest , 1822) |
The spoon dog ( Otocyon megalotis ), also spoon Fuchs or large ear Fuchs called, is a wild dog of the African Savannah , which by its mainly of termites deviates existing food from other dogs. Because of its teeth, which were simplified to adapt to insect food, it was once considered to be evolutionarily very original, but was later seen more as a specialized fox. It is named after its conspicuous, large ears, which are used to detect the slightest noises of termites in their constructions.
features
Aside from the large ears, the shape of the bucket dog is typically fox-like . The ears as the most striking feature of the species are about 13 cm long. In relation to body size, only the fennec has larger ears among dogs . The ears are not only used for hearing, but also to give off excess heat. The legs are slender and long, the tail bushy.
The head body length is 46 to 66 cm, plus 23 to 34 cm of tail. The shoulder height is 30 to 40 cm. The animals weigh 3.0 to 5.3 kg; Females are usually slightly larger and heavier than males.
The hair of the undercoat is gray with white tips and about 3 cm long; however, the outer hairs are black with a white tip and measure about 5.5 cm. At a distance the animal appears yellow-brown or gray. Older animals are usually lighter in color than younger ones. The face shows a black mask drawing that is reminiscent of a raccoon . The ears are also black; The edges of the ears, legs and tip of the tail are dark brown. Sometimes a black eel line can be seen on the back .
The front legs have five toes, the first of which has no contact with the ground. The claws measure up to 2 cm. On the hind legs there are four toes and comparatively short claws 7 to 10 mm in length.
In parts of its distribution area, the bucket dog can most likely be confused with the Cape fox , which however has smaller ears and an even bushier tail.
A special feature is the teeth. The set of teeth comprises 46 to 50 teeth - no other heterodontic (a set of teeth with differently formed groups of teeth) higher mammal has so many teeth. In adaptation to an insectivore lifestyle, the teeth are greatly reduced in size compared to the teeth of other dogs. The tooth formula is I 3/3 - C 1/1 - P 4/4 - M 3-4 / 4-5. In contrast to the special dentition of the adult animals, the milk teeth of the young are still typically dog-like.
Spoon dogs are relatively quiet. The most common sounds are high-pitched, thin howls. There is a whistling contact call between young and old animals, which is more reminiscent of a bird than a wild dog.
distribution and habitat
Shovelhounds live in two separate areas of distribution, which are characterized by the subspecies Otocyon megalotis megalotis ( nominate form ) and O. m. virgatus are inhabited. The nominate form is native to South Africa , Namibia , Botswana , Zimbabwe , Lesotho and Swaziland , as well as in the extreme south of Angola , Zambia and Mozambique .
The distribution area of the subspecies virgatus includes Ethiopia , Eritrea , Somalia , the southeast of Sudan , Kenya , Uganda , Tanzania and the north of the countries Zambia and Malawi .
The separate areas of distribution largely coincide with the distribution of the main food, the harvest termites ( Hodotermes mossambicus , Microhodotermes viator ). Another termite-eating mammal, the aardwolf , has a similar, two-part distribution area.
The habitat of the species is the savannah . Habitats in which the grass does not grow more than 25 cm high are preferred. Such habitats are created by fires or by many ungulates grazing. If the grass gets too high, spoonhounds migrate to other areas.
Way of life
activity
Shoveled dogs are both diurnal and nocturnal. There are mainly seasonal differences. In South Africa, bucket dogs are foraging by day during winter and at night in summer. In East Africa, bucket dogs are 85% active at night. The cycle seems to be closely related to termite activity.
A spoonbill pack includes two to fifteen individuals. These are family associations, i.e. a couple and their descendants. While male cubs quickly leave their parents, female offspring often remain in the pack for one or more years. The range of action of a dog-spoon pack is 0.3 to 3.5 km². The more termite structures there are in a region, the smaller the action spaces. The action spaces of different packs can overlap. When the young of a litter are fully grown, a pack leaves its previous area of activity and can be found in a different area in the following year. Scoop dogs do not mark or defend territories . This way, other packs of bucket dogs in the area are readily accepted.
Shovel dogs live in burrows that they have either dug themselves or that other animals have created and enlarged by them. In the latter case they are mostly taken over by jumping hares or aardvarks . A herd of bucket dogs can create several burrows in its action area, each with several entrances.
Spoon dogs display a number of typical canine gestures. A vigilant position taken when seeing a potential enemy includes an upright position with your mouth closed, ears erect, and eyes wide open. In case of submission or fear, the ears are put back, the head is kept low and the mouth is slightly opened.
The tail is erected during aggression, in play and during sexual arousal. When running, however, it is stretched horizontally. When an enemy approaches, the body hair on the back and tail can also be raised so that the animal appears larger.
food
The bucket dog feeds almost exclusively on insects. Termites make up the majority of the diet (around 90%) . Where the harvest determinants of the Hodotermitidae family are widespread, they provide the majority of the food. In regions of Kenya where there are no harvest termites, bucket dogs fall back on termites of the genus Odontotermes (Termitidae, Macrotermitinae). The specialization of spoon dogs on certain species of termites is so strong that in the experiment different termite species as the Erntetermite Trinervitermes trinervoides (Termitidae, Nasutitermitinae. Favorite prey of Erdwolfs Proteles cristata ) completely denied. It is believed that bucket dogs cannot tolerate the defensive secretions of the spurned termite species.
Shovel dogs reach termites with quick digging movements of the front paws, whereby the strong claws are helpful. Busy digging is always interrupted by pauses during which the spoonhound picks up its ears to locate movements of the termites in the mound.
The remaining 10% of the diet is mainly made up of other invertebrates such as ants , beetles , grasshoppers , butterflies , millipedes and scorpions . Occasionally, however, small vertebrates such as birds, lizards or rodents and fruits are also eaten.
On termite mounds you can often see spoonhounds looking for food and eating together. By contrast, they are scattered when looking for other prey and do not use group strategies.
Reproduction
Shovel dogs are usually monogamous . However, rare cases of polygyny have also been observed in which one male lived with two females.
In East Africa the young are born between the end of August and the end of October, in other regions of Africa the time can be postponed until December. Birth coincides with times of particularly great insect abundance. The gestation period is 60 to 70 days, after which one to six young are born. These are suckled for 14 to 15 weeks and during this time they are looked after by both parents; the proportion of males in the care is unusually large. The boys' eyes open after nine days; on average they leave the burrow for the first time after seventeen days and soon allow their parents to lead them to food sources. The young males leave their parents when they are about half a year old. Female offspring can also stay significantly longer and help rearing the next litter in the following year.
In captivity, bucket dogs can live to be 13 years old. In the wild, the highest age has been determined to be nine years.
Enemies
The lion , leopard , cheetah , African wild dog and spotted hyena are among the predators of the spoonhound . In one case, a pack of African wild dogs was observed to specialize in hunting spoonbills. Also fighting eagles and pythons can capture eared foxes. Black-backed jackals are the most prominent enemies of bat-eared pups.
Diseases to which bucket dogs can fall prey are rabies , canine distemper and parvovirus . Rabies epidemics, in particular, have serious effects and are the most common cause of death for bucket dogs in the Serengeti.
Tribal history
According to molecular biological studies, it is assumed that the spoonbill split off from the canid line about 7 million years ago. The oldest fossils are around 2 million years old. Due to the evolutionary history there is a proximity to the fox line; the closest relatives are seen in an adoption near the gray fox , including the island gray fox (genus Urocyon ) from North and Central America.
Very early in evolutionary history, in the Pliocene , the ancestors would have immigrated to Africa and there would have developed into the spoonhound that occurs today in 2 different places in Africa.
Other findings, however, suggest that the raccoon dog is the closest relative of the spoondog.
Systematics and evolution
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Phylogenetic systematics of dogs
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The bucket dog is the only species of its own genus Otocyon within the family of dogs (Canidae). The scientific name , given by Anselme Gaëtan Desmarest , was initially Canis megalotis . The specific epithet is Greek and means big-eared. Salomon Müller finally put the spoonhound in its own genus and named it Otocyon caffer . The generic name Otocyon is made up of the Greek words otus (ear) and cyon (dog). According to the rules of zoological nomenclature, the name combination was finally changed to the Otocyon megalotis , which is valid today , so that the ears appear twice in the name.
Because of their different teeth, bucket dogs were previously placed in their own subfamily of dogs (Otocyoninae), as no relationship to any living species of dog could be established. The simple set of teeth was thought to be a particularly original feature, but is more likely the result of an adaptation to the unusual way of life.
Humans and bucket dogs
In large parts of their area of distribution, bucket dogs are welcomed and considered useful as eaters of termites. However, they are sometimes mistakenly held responsible for killing sheep; Such misunderstandings arise when scoop dogs eat maggots from sheep carcasses. In Botswana , some locals hunt spoonhounds for their fur.
Shoveled dogs are not endangered and in some places even common. Recurring population fluctuations are related to climate changes, the availability of termites and rabies epidemics. Shovel dogs have only become rare in agricultural areas of South Africa . In the Serengeti the population density amounts to 0.3 to 1 bucket dogs per km² over a large area.
In South Africa, bucket dogs are sometimes kept as pets. They can also be seen in some international zoos . The keeping is successful because the animals are not dependent on their preferred termite food and can be accustomed to eating exclusively through fruits.
The name spoonhound refers to the large ears. In other languages it is often compared to bats because of this trait : Bat-eared Fox (English), Renard à oreilles de chauve-souris (French) or Zorro orejudo (Spanish). The name was evidently based on the Egyptian slit nose ( Nycteris thebaica ) , which is widespread throughout Africa .
Sources and further information
Sources cited
Most of the information in this article is taken from the source given under literature; the following sources are also cited:
- ↑ a b c d e R. HN Smithers, JD Skinner, Christian T. Chimimba: The Mammals of the Southern African Sub-region . Cambridge University Press 2005, pp. 470ff.
- ↑ a b c d e f g h i j Claudio Sillero-Zubiri, Michael Hoffmann, David W Macdonald: Canids: Foxes, Wolves, Jackals, and Dogs: Status Survey and Conservation . IUCN 2004, p. 183ff.
- ^ A b c d Jonathan Kingdon: East African Mammals: An Atlas of Evolution in Africa. Volume 3, Part a: Carnivores . University of Chicago Press, 1989, pp. 54ff.
- ↑ a b c d e Ronald M. Nowak: Walker's Mammals of the World. Johns Hopkins University Press, 1999, ISBN 0-8018-5789-9 , pp. 673-674 online
- ↑ a b Otocyon megalotis in the IUCN Red List of Threatened Species . Retrieved October 26, 2008.
- ↑ K. Koop, B. Velimirov: Field observations on activity and feeding of bat-eared foxes (Otocyon megalotis) at Nxai Pan, Botswana . In: African Journal of Ecology 2008, Vol. 20, No. 1, pp. 23-27.
- ↑ On the social behavior of pack-living wild canids in captivity. at carnivoreconservation.org, accessed May 26, 2018.
- ^ Richard Estes, Edward Osborne Wilson: The Behavior Guide to African Mammals: Including Hoofed Mammals, Carnivores, Primates . University of California Press 1992, pp. 392ff.
- ↑ Jan F. Kamler, David W. Macdonald: Longevity of a wild bat-eared fox . In: South African Journal of Wildlife Research 2006, Vol. 36, No. 2, pp. 199-200.
- ↑ GSA Rasmussen: Predation on bat-eared foxes Otocyon megalotis by Cape hunting dogs Lycaon pictus . In: Koedoe 1996, Vol. 39, No. 1, pp. 127-129.
- ↑ Jan AJ Nel: Wild dogs . Ed .: Udo Ganloßer, Claudio Silleo-Zubiri. Filander Verlag, 2006, ISBN 3-930831-63-5 , The Spoondog, p. 89, 90 .
- ↑ Carolyne Bardeleben, Rachael L. Moore and Robert K. Wayne: A molecular phylogeny of the Canidae based on six nuclear loci . In: Molecular Phylogenetics and Evolution 2005, Vol. 37, No. 3, pp. 815-831.
- ↑ Kerstin Lindblad-Toh et al .: "Resolving canid phylogeny." Section in: Kerstin Lindblad-Toh et al .: Genome sequence, comparative analysis and haplotype structure of the domestic dog. Nature 438, December 2005; Page 803–819.
literature
- Howard O. Clark Jr .: Otocyon megalotis . In: Mammalian Species . 2005, No. 766, pp. 1-5.
Web links
- Otocyon megalotis in the endangered Red List species the IUCN 2006. Posted by: Nel & Maas, 2004. Retrieved on 10 May, 2006.
