Brooke-Ducker

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Brooke-Ducker
Systematics
without rank: Forehead weapon bearer (Pecora)
Family : Horned Bearers (Bovidae)
Subfamily : Antilopinae
Tribe : Duiker (cephalophini)
Genre : Cephalophus
Type : Brooke-Ducker
Scientific name
Cephalophus brookei
Thomas , 1903

The Brooke duiker ( Cephalophus brookei ) is a species of duiker from western Africa . It occurs rather rarely and occurs in West Africa , where it inhabits the tropical rainforests of the lowlands. The animals are colored golden brown, characteristic is a broad dark central stripe on the back. There is hardly any information about the way of life, fruits and seeds serve as food. The species was introduced in 1903, and during the 20th century the Brooke duiker was largely considered a subspecies of the Ogilby duiker . It has only been recognized as an independent species again since the 21st century. The stock is classified as endangered due to heavy hunting.

features

Habitus

The Brooke duiker is similar to the closely related Ogilby duiker ( Cephalophus ogilbyi ). It has a head-torso length of 90 to 100 cm, a tail length of 12 cm and a shoulder height of about 50 cm. The body weight is 14 to 20 kg. The fur is characterized by a cloudy golden brown color, sometimes with a reddish tinge. The back is more strongly colored than the rather pale underside. A wide, black stripe runs along the center line of the back from the shoulders backwards, which is 2.7 to 6.6 cm wide and is much more pronounced than in the Ogilby duiker. As a rule, it thins backwards and does not reach the base of the tail. The legs are colored similarly to the back, but the insides lighten a little, darker spots of color like the Ogilby duiker are missing. The rear foot measures 19.5 cm in length. At the tip of the tail there is a clear tuft of black and white hair. In the nape of the neck there is a zone of hair that runs against the dashed line. The area will be about 3 to 4 inches wide. Another tuft of hair from reddish brown to ocher hue is formed on the forehead. The striking ears are 8.8 cm long. Both sexes have horns that protrude backwards, as is typical of Ducker. Males have horn lengths of 5.1 to 9.3 cm, in females they are significantly shorter with an average of 2.3 cm.

Skull features

The greatest length of the skull is 20.8 cm, between the zygomatic arches it is 8.8 cm wide. It is characterized by a long rostrum , so that the anterior eye area reaches about 11.5 cm in length. The median jawbone and the nasal bone touch over a great length, the frontal bone is comparatively large. It is noticeable that the clear swellings in the forehead area that characterize the skull of the Ogilby ducker are missing. The dental formula is: . Typically for those with horns, the dentition consists of 32 teeth. The upper row of teeth is 5.7 cm long.

distribution

The Brooke duiker is common in West Africa. It occurs from Sierra Leone westwards to Ghana west of the Volta . The species rarely appears. In Sierra Leone it is only occupied for the Outamba Kilimi National Park in the north of the country and for Lalehun in the southeast. In Liberia there is evidence from the eastern and southeastern parts of the country, in Côte d'Ivoire from the southwestern ( Taï National Park ), and an occurrence in the southeast of the country is also suspected. In Ghana, too, the Brooke duiker has so far only been observed in the south and south-west, for example in the Bomfobiri and Owabi game reserves ; a single sighting over a period of 10 years comes from the Kakum National Park . Reports of an occurrence in southeastern Guinea are so far unconfirmed. Accordingly, the distribution area of ​​the Brooke ducker includes the forest areas of West Africa ( Upper Guinean forest block ). The animals prefer humid tropical rainforests of the lowlands, the altitude range extends up to 1000 m. Occasionally it also appears in secondary forests or in farmland. The maximum population density in areas with a higher population is estimated at 2 individuals per square kilometer. The total stock may not exceed 5000 animals.

Way of life

The Brooke ducker's way of life has hardly been researched. Like the other duikers, it probably lives solitary and is diurnal. An animal caught in Liberia was active around 58% of the daytime but only 17% of the nighttime. According to analyzes of stomach contents from the Taï National Park , 92% of the food consists mainly of fruits and seeds , the remainder is made up of flowers and vegetative plant parts. Especially often the animals consume representatives of carob plants as Dialium or leguminous plants such Amphimas or nutmeg plants as Coelocaryon . In addition, parts of are ebony trees , Nauclea or Scottelia eaten. There is no information about reproduction, the fur of the young is spotted.

Systematics

The Brooke duiker is a species from the genus Cephalophus and the family of horned bearers (Bovidae). The genus forms within the horn-bearers together with Sylvicapra and Philantomba the tribe of duikers (Cephalophini). The duikers mainly include smaller to medium-sized as well as compactly built representatives of the horn-bearers. They are endemic in Africa, with the exception of the members of Sylvicapra , who inhabit savanna landscapes , they are animals adapted to wooded habitats .

The genus Cephalophus is the most species-rich group of duikers. Molecular genetic studies from 2001 revealed a total of three lines of development within the genus. These include the giant duiker with the jentink duiker ( Cephalophus jentinki ) and the black- backed duiker ( Cephalophus dorsalis ), as well as the West African red duiker, such as the St. Peter's duiker ( Cephalophus callipygus ), the black duiker ( Cephalophus niger ) or the ogilby duiker ( Cephalophus ) o ( Cephalophus ) also the East African red duiker, such as the natal red duiker ( Cephalophus natalensis ) and the Harvey red duiker ( Cephalophus harveyi ). This division of the genus Cephalophus could in principle be confirmed by later studies published in 2012. In general, the Brooke duiker is regarded as closely related to the Ogilby duiker and is therefore close to the West African red duiker. The splitting of the West African red duiker began in the Middle Pliocene around 3.7 million years ago. As a further result of the genetic investigations it turned out that Sylvicapra is the sister group of the giant duiker, which makes the genus Cephalophus paraphyletic . Therefore, perhaps the red duiker in need Cephalophus are released, it was suggested Cephalophorus as a generic name for this.

The Ogilby-Ducker from The book of antelopes 1894, Oldfield Thomas as the first describer of the Brooke -Ducker suspects that the illustration corresponds more to his newly introduced species

The first scientific description of the Brooke ducker was in 1903 by Oldfield Thomas . The basis was formed by two individuals of both sexes and a young animal from the area around Fanti near Cape Coast in Ghana , the area forms the type region of the species. The holotype is represented by a fully grown male with a body length of 90 cm and shoulder height of 50 cm. Victor Brooke acquired this, and the additional species brookei also refers to it . Later, his son Douglas Brooke gave the individual along with his father's collection to the Natural History Museum in London. Thomas introduced the Brooke duiker as an independent species, but saw it as a continental form of the Ogilby duiker, which was named by George Robert Waterhouse in 1838 and was only known from the island of Bioko in the Gulf of Guinea at that time . Around a decade later, Ernst Schwarz identified the Brooke duiker as a subspecies of the Ogilby duiker, which was confirmed by Jane St. Leger in 1936. This status persisted for more than 60 years, in 1978 Peter Grubb introduced the white-legged ducker ( Cephalophus crusalbum ) as the third subspecies of the Ogilby duiker. It was only in the transition from the 20th to the 21st century that the Brooke duiker was first released from the Ogilby duiker. A revision of the ungulates, which was published in 2011 by Colin Peter Groves and Peter Grubb, then also recognized the white-legged eater as independent. Other systematics assign the two forms to the Ogilby duiker, but show the latter as a species complex that includes three allopatric species.

Threat and protection

The Brooke duiker is hunted intensively and some of the meat from the animals is sold on the local bushmeat markets. Further threats to the stock are the destruction of forests through logging or conversion into agriculturally usable areas. Since 2000 there has been a decline in the population of an estimated 10%. The IUCN currently classifies the species as "threatened" ( vulnerable ), a higher degree of endangerment may be necessary. It is present in several protected areas, such as the Outamba Kilimi National Park in Sierra Leone , the Sapo National Park in Liberia , the Taï National Park in Côte d'Ivoire and the Kakum National Park in Ghana .

literature

  • Colin P. Groves and David M. Leslie Jr .: Family Bovidae (Hollow-horned Ruminants). In: Don E. Wilson and Russell A. Mittermeier (eds.): Handbook of the Mammals of the World. Volume 2: Hooved Mammals. Lynx Edicions, Barcelona 2011, ISBN 978-84-96553-77-4 , pp. 765-766
  • Jonathan Kingdon: Cephalophus ogilbyi Ogilby's Duiker. In: Jonathan Kingdon, David Happold, Michael Hoffmann, Thomas Butynski, Meredith Happold and Jan Kalina (eds.): Mammals of Africa Volume VI. Pigs, Hippopotamuses, Chevrotain, Giraffes, Deer and Bovids. Bloomsbury, London, 2013, pp. 272-275

Individual evidence

  1. ^ A b c Oldfield Thomas: A new duiker from West Africa. Annals and Magazine of Natural History 7 (11), 1903, pp. 289-291 ( [1] )
  2. ^ A b c Peter Grubb: A new antelope from Gabon. Zoological Journal of the Linnean Society 62 (4), 1978, pp. 373-380
  3. ↑ a b c d Colin P. Groves and David M. Leslie Jr .: Family Bovidae (Hollow-horned Ruminants). In: Don E. Wilson and Russell A. Mittermeier (eds.): Handbook of the Mammals of the World. Volume 2: Hooved Mammals. Lynx Edicions, Barcelona 2011, ISBN 978-84-96553-77-4 , pp. 765-766
  4. ↑ a b c d e Jonathan Kingdon: Cephalophus ogilbyi Ogilby's Duiker. In: Jonathan Kingdon, David Happold, Michael Hoffmann, Thomas Butynski, Meredith Happold and Jan Kalina (eds.): Mammals of Africa Volume VI. Pigs, Hippopotamuses, Chevrotain, Giraffes, Deer and Bovids. Bloomsbury, London, 2013, pp. 272-275
  5. ↑ a b Helen Newing: Bushmeat hunting and management: implications of duiker ecology and interspecific competition. Biodiversity and Conservation 10 (1), 2001, pp. 99-108
  6. ↑ a b c IUCN SSC Antelope Specialist Group: Cephalophus ogilbyi ssp. brookei. The IUCN Red List of Threatened Species 2016. e.T136902A50198130 ( [2] ); last accessed on September 25, 2016
  7. ↑ a b c Anne R Johnston and Nicola M Anthony: A multi-locus species phylogeny of African forest duikers in the subfamily Cephalophinae: evidence for a recent radiation in the Pleistocene. BMC Evolutionary Biology, 12, 2012, p. 120 ( [3] )
  8. ↑ Bettine Jansen van Vuuren and Terence J. Robinson: Retrieval of Four Adaptive Lineages in Duiker Antelope: Evidence from Mitochondrial DNA Sequences and Fluorescence in Situ Hybridization. Molecular Phylogenetics and Evolution 20 (3), 2001, pp. 409-425
  9. ↑ Alexandre Hassanin, Frédéric Delsuc, Anne Ropiquet, Catrin Hammer, Bettine Jansen van Vuuren, Conrad Matthee, Manuel Ruiz-Garcia, François Catzeflis, Veronika Areskoug, Trung Thanh Nguyen and Arnaud Couloux: Pattern and timing of diversification of Cetartiodactalia, Lauriala (Mammia ), as revealed by a comprehensive analysis of mitochondrial genomes. Comptes Rendus Palevol 335, 2012, pp. 32-50
  10. ^ Colin Groves: Current taxonomy and diversity of crown ruminants above the species level. Zitteliana B 32, 2014, pp. 5-14
  11. ^ Philip Lutley Sclater and Oldfield Thomas: The Book of Antelopes. Volume I. London, 1894–1900, plate 18 ( [4] ).
  12. ^ George Robert Waterhouse: On some new species of Mammalia from Fernando Po. Proceedings of the Zoological Society 1838, pp. 57-61 ( [5] )
  13. ^ Richard Lydekker: Catalog of the ungulate mammals in the British Museum (Natural History). Volume II. London, 1914, pp. 1–295 (pp. 84–85) ( [6] )
  14. ^ Ernst Schwarz: Notes on African ungulates. Annals and Magazine of Natural History 8 (13), 1914, pp. 491–495 ( [7] )
  15. ^ J. St. Leger: A key to the species and subspecies of the subgenus Cephalophus. Proceedings of the Zoological Society of London 1936, pp. 209-228
  16. ^ Fenton PD Cotterill: Species concepts and the real diversity of antelopes. In: A. Plowman (Ed.): Ecology and Conservation of Mini-antelope: Proceedings of an International Symposium on Duiker and Dwarf Antelope in Africa. Fuerth. 2003, pp. 59-118
  17. ↑ Peter Grubb: Genus Cephalophus. In: Don E. Wilson and DeeAnn M. Reeder (Eds.): Mammal Species of the World. A taxonomic and geographic Reference. Johns Hopkins University Press, Baltimore MD 2005, ISBN 0-8018-8221-4 ( [8] )
  18. ↑ Colin Groves and Peter Grubb: Ungulate Taxonomy. Johns Hopkins University Press, 2011, pp. 1–317 (SS 272–273)

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