Kirk's dik-dik

Last updated

Kirk's dik-dik
Madoqua kirkii - male (Namutoni).jpg
Male
Madoqua kirkii - female (Namutoni).jpg
Female
Both at the Etosha National Park in Namibia
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Artiodactyla
Family: Bovidae
Subfamily: Antilopinae
Genus: Madoqua
Species:
M. kirkii
Binomial name
Madoqua kirkii
(Günther, 1880)
Subspecies

4 ssp., see text

Madoqua kirkii map.png
Range

Kirk's dik-dik (Madoqua kirkii) is a species of small dik-dik antelope native to Eastern and Southern Africa. [1] [2] It is believed to have six subspecies and possibly a seventh existing in southwest Africa. [3] Dik-diks are herbivores, typically of a fawn color that aids in camouflaging themselves in savannah habitats. [3] According to MacDonald (1985), they are also capable of reaching speeds up to 42 km/hour. [4] The lifespan of Kirk's dik-dik in the wild is typically 5 years, but may surpass 10 years. [4] In captivity, males have been known to live up to 16.5 years, while females have lived up to 18.4 years. [4]

Contents

Etymology

The dik-dik's name is derived from its call. [2] When they feel threatened, dik-diks lie low to prevent detection. [2] If they are discovered, they run in a swift, zigzag-like pattern until they reach refuge in a nearby thicket. [2] During this 'flight', they emit trumpet-like "zik-zik" calls to raise an alarm or to harass predators and publicize the presence of a mated pair. [2]

Physical characteristics

Dik-diks are some of the world's smallest antelopes, with the largest, the Kirk's dik-dik, standing between 14 and 18 inches tall and weighing no more than 7.2 kg (16 lb). [2] Female dik-diks tend to be 1 to 2 pounds heavier than males. [2] They are dainty creatures with a pointed, mobile snout, large eyes and ears, prominent preorbital glands, pipestem legs, hare-like hind limbs that are significantly larger than their forelimbs, and a vestigial tail. [2] Their coats, depending upon their habitat, [5] range from grey to gray-brown with tan flanks, limbs, and an erectile head crest and whitish eye rings, ear lining, underparts, and rump. [2]

Only male dik-diks sport horns, which are about 3 in (8 cm) long, corrugated, and backward-slanted. [2] Horns of male Kirk's dik-diks may be straight or curved backwards from the profile of the face, and the basal half of the horns have seven to nine annular ridges that are frequently covered by the crest. [4] Kirk's dik-diks are sexually dimorphic; females are larger and lack horns, while males sport a more developed muzzle, have a longer crest, and tend to be lighter in color. [6] Though physically very similar, Kirk's dik-dik can be distinguished from Guenthers' dik-dik by its longer nasals and premaxillae and shorter proboscis, which gives the head a more wedged-shaped profile than that of Guenther's dik-dik. [4]

Adaptations

Kirk's dik-diks are highly adapted to surviving in the arid regions of eastern Africa. They have a hairy proboscis with tiny, slit-like nostrils, a feature that is most pronounced in Guenther's dik-diks. [7] This proboscis contains an enlarged nasal chamber supplied with a rich amount of blood that is cooled by rapid nasal panting. [7] Panting through their snouts leads to airflow and evaporation that cools the blood before it is pumped back into the body. This process is also efficient, because it results in a minimal loss of water in the exhaled air. [2] Water- and energy-conserving methods, such as fluctuating body temperatures, lowered metabolic rates, concentrated urine, and dry feces, all contribute to the ability of the dik-dik to survive harsh arid climates. [2] Further, [8] they also conserve fluids by licking dew from their nose and reabsorbing water from their feces. [4] When compared to cattle, dik-diks have a significantly lower density of sweat glands. [4]

Behaviorally, dik-diks are highly nocturnal, and during the daytime seek shade to rest throughout the hottest parts of the day to help avoid the loss of valuable fluids. [7] Dik-diks are also highly selective when browsing on succulents, herbs, and foliage as to maximize fluid acquisition. [2] The hind legs of Kirk's dik-diks are longer and are structurally more uniform, than the fore legs. [4] Hopwood 1936 suggests this helps the hind legs propel the dik-dik forward, as the relatively short fore legs of dik-diks are more efficient at ascending broken terrain. [4]

Habitat and territoriality

Females, Etosha National Park, Namibia Dikdik.jpg
Females, Etosha National Park, Namibia

"Kirk's dik-dik are endemic to savannah areas of eastern and southwestern Africa, occurring primarily in the Somali and Southwest arid biotic zones, but encroaching into the Southern savannah biotic zone". [4] Their distribution can be described as discontinuous and as a result they often occur in dispersed patches due to their unique habitat requirements. [4] In Namibia, Kirk's dik-dik occur in isolated areas along the Fish River and do not reside in the Namib desert, though they may traverse desert thickets along sources of water. [4] They prefer habitats with good cover but lacking tall vegetation. [5] Ideal habitats contain a variety of browse, extensive shade, and an open understory at their eye level. [4] (Tinley, 1969) As a result, they move to different ranges when grass grows too high and obstructs their view. [5] As noted by Tinley (1969), typical habitats of Kirk's dik-dik consist of thicket mosaics characterized by well-developed shrub layers and scant short grass cover. [4] Dik-diks live in pairs on territories of 2–86 acres, depending on cover and resources. [2] If no unfavorable events occur a pair of Kirk's dik-dik may reside within the same territory for life. [9] Males are the main defenders of territories, as females are unable to maintain territories themselves. [4] (Kingdon 1982) According to MacDonald (1985), territorial conflicts over quality habitat are not frequent, however, when do they occur, males charge one another, stopping just short of physical contact, before repeating the process by running from a longer distance. [4] Furthermore, the encounter ends when one male surrenders, which results in both males scratching at the ground, urinating, and defecating". [4]

Diet

Dik-dik are herbivorous and their diets consist mainly of foliage, fruits, shoots, and berries. [7] Due to their adaptations, dik-diks are water-independent and rely on vegetation as a source of water. [7] Kirk's dik-diks are concentrate selectors, feeding selectively on dicotyledonous plants that can be rapidly fermented and digested. This includes leaves and fruit high in nutrients and water, but low in fiber and cellulose. Grasses are only consumed when they are germinating and Kirk's dik-diks have stomach capacities and mass that consist of 8.5–10.0% of body mass when full and 2.2% when empty". [4] Because of the aforementioned facts and their high food requirements, Kirk's dik-diks feed and ruminate periodically throughout day and night. [4] They consume roughly 3.8% of their body mass daily. [4]

Reproduction and behavior

Similar to other dwarf antelopes, Kirk's dik-diks exist in monogamous pairs on territories. [2] Territories are marked with dung and urine that are deposited in a ritual that is performed to help maintain pair bonds. [2] During the ritual, the female will excrete, followed by the male, which samples the female's urine stream to check her reproductive capacity. [2] He paws over and then marks his dung and urine over her deposit. [2] Finally, the pair marks nearby twigs with secretions from their preorbital glands. [2] The male courts the female by running up behind her with his head and neck stretched and his muzzle pointing out in front. Copulation begins with the male standing on his hind legs behind the female and waving his forelegs at an acute angle to his own body in the air over her back". [4] Copulation typically occurs three to five times within a 9-hour period. [4]

Kirk's dik-diks have a gestation period of 5–6 months, and may produce up to two offspring per year. [2] Females reach sexual maturity between 6 and 8 months of age, while this occurs for males between 8 and 9 months. [9] Dik-diks produce one offspring per gestation. [2] Most births occur between November and December and April through May, which coincides with the timing of the rainy seasons. [4] Dik-diks differ from other ruminants in that offspring are born with their fore legs along the body, rather than extended forward. [4] After birth, the offspring lie concealed away from their mother 2–3 weeks, and survival rates for fawns are roughly 50%. [4] [9] Once offspring reach a certain age, they also begin to participate in the bonding ritual, and remain with the parents until another offspring is born. [2] At this point, the parents chase the older sibling out of their territory. [7] The older offspring then seeks out its own territory and mate. [2]

Genetics

Dik-diks in general have complex chromosomal arrangements. [10] They typically have 2n=46 to 2n=48 arrangements; however, dik-diks with 2n=49 have been discovered, as well. [10] Furthermore, some have 47 chromosomes with X/A translocation. [10] The two common cytotypes (46- and 48-chromosome individuals) are different enough so that resulting hybrids are sterile. [10] Many zoos are now known to harbor hybrids between different cytotypes, with anomalous chromosome numbers and causing unexplained sterility. [10] Examination of these individuals shows a lack of spermatogenesis in males, for example hybrids between Kirk's and Guenther's dik-diks are infertile. [10]

Predators

Dik-diks are susceptible to a myriad of predators including eagles, wildcats, jackals, caracals, leopards, hyenas, cheetahs, Cape wild dogs, honey badgers, crocodiles, pythons, lions, monitors, and humans. [2] [7] [9] Young dik-diks are particularly preyed upon by baboons, genets, and eagles. Dik-diks have fine-tuned senses of hearing, sight, and smell. When they feel in danger or hear the alarm calls of other animals, they hide, rather than flee. Only when frightened or disturbed do they emit their iconic "zik-zik" alarm.

Human impacts and interactions

Humans are the greatest threat to dik-diks, which are sometimes hunted for their hides and bones, often using snares. [5] The bones from their legs and feet are used in traditional jewelry, while their hides are fashioned into suede gloves. [5] An entire dik-dik hide is required to produce a single glove. [4] Nowak (1991) asserted that dik-dik are disliked by local hunters because they flush and warn larger game to the presence of humans. [4] Dik-diks also benefit from the destruction of vegetation via human-mediated slash-and-burn agriculture that results in the subsequent secondary growth of shrubs that serve as a food source and place of refuge for dik-diks. [4] The IUCN Redlist lists Kirk's dik-dik as "least concern". [1]

Subspecies

Usually, four subspecies of Kirk's dik-dik are distinguished, but they may represent three or more distinct species: [11]

Related Research Articles

<span class="mw-page-title-main">Antelope</span> Term referring to an even-toed ruminant

The term antelope refers to numerous extant or recently extinct species of the ruminant artiodactyl family Bovidae that are indigenous to most of Africa, India, the Middle East, Central Asia, and a small area of Eastern Europe. Antelopes do not form a monophyletic group, as some antelopes are more closely related to other bovid groups, like bovines, goats, and sheep, than to other antelopes.

<span class="mw-page-title-main">Klipspringer</span> Species of mammal

The klipspringer is a small antelope found in eastern and southern Africa. The sole member of its genus and subfamily/tribe, the klipspringer was first described by German zoologist Eberhard August Wilhelm von Zimmermann in 1783. The klipspringer is a small, sturdy antelope; it reaches 43–60 centimetres at the shoulder and weighs from 8 to 18 kilograms. The coat of the klipspringer, yellowish gray to reddish brown, acts as an efficient camouflage in its rocky habitat. Unlike most other antelopes, the klipspringer has a thick and coarse coat with hollow, brittle hairs. The horns, short and spiky, typically measure 7.5–9 cm.

<span class="mw-page-title-main">Zanzibar red colobus</span> Species of Old World monkey

The Zanzibar red colobus is a species of red colobus monkey endemic to Unguja, the main island of the Zanzibar Archipelago, off the coast of Tanzania. It is also known as Kirk's red colobus after Sir John Kirk, the British Resident of Zanzibar who first brought it to the attention of zoological science. It is now classified as an endangered species and in the mid-1990s was adopted as the flagship species for conservation in Zanzibar. The population is still decreasing, and conservationists are attempting to work with the local government to devise a proper, effective strategy to protect the population and habitat. Challenges include the species' habitat, which is limited to the archipelago. The species has been reclassified three times; it was previously in the genus Colobus, then in the genus Procolobus, and later in the genus Piliocolobus.

<span class="mw-page-title-main">Dik-dik</span> Genus of antelopes found in Africa

A dik-dik is the name for any of four species of small antelope in the genus Madoqua that live in the bushlands of eastern and southern Africa.

<span class="mw-page-title-main">Addax</span> Species of antelope native to the Sahara

The addax, also known as the white antelope and the screwhorn antelope, is an antelope native to the Sahara Desert. The only member of the genus Addax, it was first described scientifically by Henri de Blainville in 1816. As suggested by its alternative name, the pale antelope has long, twisted horns – typically 55 to 80 cm in females and 70 to 85 cm in males. Males stand from 105 to 115 cm at the shoulder, with females at 95 to 110 cm. They are sexually dimorphic, as the females are smaller than the males. The colour of the coat depends on the season – in the winter, it is greyish-brown with white hindquarters and legs, and long, brown hair on the head, neck, and shoulders; in the summer, the coat turns almost completely white or sandy blonde.

<span class="mw-page-title-main">Sitatunga</span> Species of swamp-dwelling antelope

The sitatunga or marshbuck is a swamp-dwelling medium-sized antelope found throughout central Africa, centering on the Democratic Republic of the Congo, the Republic of the Congo, Cameroon, parts of Southern Sudan, Equatorial Guinea, Burundi, Ghana, Botswana, Rwanda, Zambia, Gabon, the Central African Republic, Tanzania, Uganda and Kenya. The sitatunga is mostly confined to swampy and marshy habitats. Here they occur in tall and dense vegetation as well as seasonal swamps, marshy clearings in forests, riparian thickets and mangrove swamps.

<span class="mw-page-title-main">Lesser kudu</span> Species of antelope

The lesser kudu is a medium-sized bushland antelope found in East Africa. The species is a part of the ungulate genus Tragelaphus, along with several other related species of striped, spiral-horned African bovids, including the related greater kudu, the bongo, bushbuck, common and giant elands, nyala and sitatunga. It was first scientifically described by English zoologist Edward Blyth (1869).

<span class="mw-page-title-main">Royal antelope</span> Species of mammal

The royal antelope is a West African antelope recognized as the world's smallest. It was first described by Swedish zoologist Carl Linnaeus in 1758. It stands up to merely 25 cm (10 in) at the shoulder and weighs 2.5–3 kg (5.5–6.6 lb). A characteristic feature is the long and slender legs, with the hindlegs twice as long as the forelegs. Horns are possessed only by males; the short, smooth, spiky horns measure 2.5–3 cm (0.98–1.18 in) and bend backward. The soft coat is reddish to golden brown, in sharp contrast with the white ventral parts. In comparison to Bates's pygmy antelope, the royal antelope has a longer muzzle, broader lips, a smaller mouth and smaller cheek muscles.

<span class="mw-page-title-main">Blackbuck</span> Antelope native to India and Nepal

The blackbuck, also known as the Indian antelope, is a medium-sized antelope native to India and Nepal. It inhabits grassy plains and lightly forested areas with perennial water sources. It stands up to 74 to 84 cm high at the shoulder. Males weigh 20–57 kg (44–126 lb), with an average of 38 kg (84 lb). Females are lighter, weighing 20–33 kg (44–73 lb) or 27 kg (60 lb) on average. Males have 35–75 cm (14–30 in) long corkscrew horns, and females occasionally develop horns, as well. The white fur on the chin and around the eyes is in sharp contrast with the black stripes on the face. Both sexes' coats feature a two-tone colouration; in males, the majority of the body is dark brown to black, with white circles around the eyes, white ears and tail, and the belly, lower jaw, and inner legs also white. Females and juveniles are yellowish-fawn to tan and display the same white areas, only with more of a beige tone than the males. Females also feature a more pronounced horizontal white side-stripe, starting around the shoulder and ending at the rump. The blackbuck is the sole living member of the genus Antilope and was described by Carl Linnaeus in 1758. Two subspecies are recognized.

<span class="mw-page-title-main">Antilopinae</span> Subfamily of mammals

The antilopines are even-toed ungulates belonging to the subfamily Antilopinae of the family Bovidae. The members of tribe Antilopini are often referred to as true antelopes, and include the gazelles, blackbucks, springboks, gerenuks, dibatags, and Central Asian gazelles. True antelopes occur in much of Africa and Asia, with the highest concentration of species occurring in East Africa in Sudan, Eritrea, Ethiopia, Somalia, Kenya, and Tanzania. The saiga inhabits Central and Western Asia, mostly in regions from the Tibetan Plateau and north of the Indian Subcontinent. The dwarf antelope species of tribe Neotragini live entirely in sub-Saharan Africa.

<span class="mw-page-title-main">Bohor reedbuck</span> Species of mammal

The bohor reedbuck is an antelope native to central Africa. The animal is placed under the genus Redunca and in the family Bovidae. It was first described by German zoologist and botanist Peter Simon Pallas in 1767. The bohor reedbuck has five subspecies. The head-and-body length of this medium-sized antelope is typically between 100–135 cm (39–53 in). Males reach approximately 75–89 cm (30–35 in) at the shoulder, while females reach 69–76 cm (27–30 in). Males typically weigh 43–65 kg (95–143 lb) and females 35–45 kg (77–99 lb). This sturdily built antelope has a yellow to grayish brown coat. Only the males possess horns which measure about 25–35 cm (9.8–13.8 in) long.

<span class="mw-page-title-main">Oribi</span> Species of mammal

The oribi is a small antelope found in eastern, southern and western Africa. The sole member of its genus, it was described by the German zoologist Eberhard August Wilhelm von Zimmermann in 1783. While this is the only member in the genus Ourebia, eight subspecies are identified. The oribi reaches nearly 50–67 centimetres (20–26 in) at the shoulder and weighs 12–22 kilograms (26–49 lb). It possesses a slightly raised back, and long neck and limbs. The glossy, yellowish to rufous brown coat contrasts with the white chin, throat, underparts and rump. Only males possess horns; the thin, straight horns, 8–18 centimetres (3.1–7.1 in) long, are smooth at the tips and ringed at the base.

<span class="mw-page-title-main">Dibatag</span> Genus of mammals

The dibatag, or Clarke's gazelle, is a medium-sized slender antelope native to Ethiopia and Somalia. Though not a true gazelle, it is similarly marked, with long legs and neck. It is often confused with the gerenuk due to their striking resemblance. The typical head-and-body length is about 103 to 117 cm. They stand up to about 80 to 90 cm. Male dibatag weigh between 20 and 35 kg, whereas females range from 22 and 29 kg. The length of the curved horns, present only on males, is typically between 10 and 25 cm. The upper parts are gray to fawn, while the dorsal and lateral areas are cinnamon to rufous. The underparts, rump and the insides of the legs are all white. While markings are visible on the face, there are none on the flanks or the buttocks.

<span class="mw-page-title-main">Patagonian mara</span> Species of rodent

The Patagonian mara is a relatively large rodent in the mara genus Dolichotis. It is also known as the Patagonian cavy or Patagonian hare. This herbivorous, somewhat rabbit-like animal is found in open and semiopen habitats in Argentina, including large parts of Patagonia. A population has also been recorded in the northern United Arab Emirates, possibly as a result of escaped pets or captive animals. It is monogamous, but often breeds in warrens shared by several pairs.

<span class="mw-page-title-main">Red-flanked duiker</span> Species of mammal

The red-flanked duiker is a species of small antelope found in western and central Africa in countries as far apart as Senegal and Sudan. Red-flanked duikers grow to almost 15 in (38 cm) in height and weigh up to 31 lb (14 kg). They have russet coats, with greyish-black legs and backs, and white underbellies. They feed on leaves, fallen fruits, seeds and flowers, and sometimes twigs and shoots. The adults are territorial, living in savannah and lightly wooded habitats, and the females usually produce a single offspring each year. They have lifespans of ten to fifteen years in captivity.

<span class="mw-page-title-main">Przewalski's gazelle</span> Species of mammal

Przewalski's gazelle is a member of the family Bovidae, and in the wild, is found only in China. Once widespread, its range has declined to six populations near Qinghai Lake. The gazelle was named after Nikolai Przhevalsky, a Russian explorer who collected a specimen and brought it back to St. Petersburg in 1875.

<span class="mw-page-title-main">Salt's dik-dik</span> Species of mammal

Salt's dik-dik is a small antelope found in semidesert, bushland, and thickets in the Horn of Africa, but marginally also in northern Kenya and eastern Sudan. It is named after Henry Salt, who was the first European to acknowledge the species in Abyssinia in the early 19th century.

<span class="mw-page-title-main">Günther's dik-dik</span> Species of mammal

Günther's dik-dik is a small antelope found in arid zones of East Africa.

<span class="mw-page-title-main">Tragelaphini</span> Tribe of antelopes

The tribe Tragelaphini, or the spiral-horned antelopes, are bovines that are endemic to sub-Saharan Africa. These include the bushbucks, kudus, and the elands. The scientific name is in reference to the mythical creature the tragelaph, a Chimera with the body of a stag and the head of a goat. They are medium-to-large, tall, long-legged antelopes characterized by their iconic twisted horns and striking pelage coloration patterns.

<span class="mw-page-title-main">Preorbital gland</span> Paired exocrine gland in many hoofed animals

The preorbital gland is a paired exocrine gland found in many species of artiodactyls, which is homologous to the lacrimal gland found in humans. These glands are trenchlike slits of dark blue to black, nearly bare skin extending from the medial canthus of each eye. They are lined by a combination of sebaceous and sudoriferous glands, and they produce secretions which contain pheromones and other semiochemical compounds. Ungulates frequently deposit these secretions on twigs and grass as a means of communication with other animals.

References

  1. 1 2 3 IUCN SSC Antelope Specialist Group (2016). "Madoqua kirkii". IUCN Red List of Threatened Species . 2016: e.T12670A50190709. doi: 10.2305/IUCN.UK.2016-1.RLTS.T12670A50190709.en . Retrieved 12 November 2021.
  2. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Estes, Richard. "dik-dik - antelope". Encyclopædia Britannica. Archived from the original on Mar 27, 2012.
  3. 1 2 "Kirk's dik-dik". Twycross Zoo. Archived from the original on 2015-11-25. Retrieved 2015-04-29.
  4. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 Scheibe, Elizabeth (1999). "Madoqua kirkii: Information". Animal Diversity Web. Archived from the original on Nov 28, 2023.
  5. 1 2 3 4 5 "Dik-Dik". African Wildlife Foundation. Archived from the original on Feb 20, 2024.
  6. Kingswood, Steven C.; Kumamoto, Arlene T. (24 October 1997). "Madoqua kirkii" (PDF). Mammalian Species. American Society of Mammalogists. Archived from the original (PDF) on 2015-09-05. Retrieved 2015-04-29 via Clark Science Center.
  7. 1 2 3 4 5 6 7 Sarah Zielinski (August 1, 2011). "What In The World Is A Dik-dik?". Smithsonian Magazine. Archived from the original on Feb 4, 2023.
  8. Hoppe 1977b, Kamau 1988, and Maloiy et al., 1988,
  9. 1 2 3 4 "Kirk's dik-dik". www.ultimateungulate.com.
  10. 1 2 3 4 5 6 "Comparative Placentation".
  11. Grubb, P. (2005). Wilson, D. E.; Reeder, D. M. (eds.). Mammal Species of the World: A Taxonomic and Geographic Reference (3rd ed.). Baltimore, MD: Johns Hopkins University Press. ISBN   0-8018-8221-4. OCLC   62265494.