Helogale parvula, Gray, 1862
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publication ID |
https://doi.org/ 10.5281/zenodo.5676639 |
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DOI |
https://doi.org/10.5281/zenodo.5698489 |
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persistent identifier |
https://treatment.plazi.org/id/143F87B3-FFD8-FF9F-FA14-9D44F99DF83F |
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treatment provided by |
Conny |
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scientific name |
Helogale parvula |
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30. View On
Common Dwarf Mongoose
French: Mangouste naine / German: Zwergmanguste / Spanish: Mangosta enana
Other common names: Dwarf Mongoose.
Taxonomy. Herpestes parvulus Sundevall, 1847 ,
Transvaal, South Africa.
Seven subspecies are recognized, but a revision is needed.
Subspecies and Distribution.
H. p. parvula Sundevall, 1847 — NE South Africa, Mozambique, and Zimbabwe.
H. p. wore Thomas, 1919 — NE Mozambique and Tanzania.
H. p. mimetra Thomas, 1926 — NW Botswana and N Namibia.
H. p. nero Thomas, 1928 — C Namibia.
H. p. ruficeps Kershaw, 1922 — Zambia (Southern Province & Kafue area).
H. p. undulata Peters, 1852 — N & E Africa from Ethiopia and Sudan to Malawi.
H. p. varia Thomas, 1902 — C Africa from Angola to Uganda. View Figure
Descriptive notes. Head-body 16-22. 7 cm (males), 18.5-23 cm (females), tail 15-2— 18: 3 cm (males), 14:2-18. 8 cm (females), hindfoot 4.1-5. 1 cm (males), 4.1-4. 9 cm (females), ear 1.5-2. 1 cm (males), 1.4-2. 1 cm (females). Weight 223-341 g (males), 213-341 g (females) for Botswana population; Serengeti ( Tanzania) population heavier: weight 265-415 g (males), 221-395 g (females). No obvious sexual dimorphism. Smallest of the mongooses. Body covered with smooth hair. Uniform coat color varies geographically from yellow to dark brown. Hair on head is short (2-3 mm), gradually increasing towards tail, reaching 15 mm on rump, 18 mm on tail. Individual guard hairs are dark with whitish annulations, one near the tip, and the other closer to the body. Dense underfur; dark at base, lighter near tip (in lighter morphs). Hair on underparts is sparser than on upper body, but similar in color. Domed head with pointed muzzle. Ears small and rounded. Rhinarium tiny with shallow depression between nostrils. Tail approximately half overall length. Five digits. Foreclaws elongated (up to 10 mm) and strong for digging, hindclaws shorter (up to 8 mm). There are three pairs of abdominal mammae. Anus and anal gland openings enclosed in anal subcircular pouch. Pear-shaped brain case. Postorbital bars incomplete. Supraorbital crest well-developed. Low, ridged sagittal crest. Relatively heavy zygomatic arches. Front chambers of ear bullae slightly larger than hind. Short rostrum (1/4 total skull length). Eye sockets relatively small in diameter (one fifth of total skull length). Dental formula: 13/3, C 1/1,P3/3,M2/2=236. Sharp, strong teeth, especially canines. Carnassials not adapted for slicing. Relatively large upper canines reaching below base of lower canines. Molars have high cusps, an adaptation to insectivory. Outer upper incisors larger than inner.
Habitat. Found in a wide range of habitats, principally in savannah, tree savannah, woodland, and dry bush. Also occurs in forests. Associated with termitaria, which are used as dens. In Zimbabwe, not found above 1100 m.
Food and Feeding. Predominantly insectivorous diet, especially Coleoptera (beetles) and termites, but also Myriapoda (centipedes), larvae, and occasional small vertebrates (including small mammals, geckos, snakes, and birds). Common Dwarf Mongooses move as a group, but individuals spread out to forage while the group is moving. Examination of 160 scats from Natal ( South Africa), found the following frequency of occurrence of food types: Coleoptera (79%), Orthoptera (64%), Myriapoda (34%), Arachnida (21%), Seeds (12%), Isoptera (8%), Hemiptera (8%), Lepidoptera (4%), and Mammalia (1%). Frequency of occurrence of food types in 27 stomachs collected from the northern area of southern Africa: Insecta (undetermined) (44%), Coleoptera adults (37%) and grubs (33%), Orthoptera (33%), Isoptera (33%), Araneae (11%), Muridae (4%), Myriapoda (4%), Reptilia (4%), Scorpiones (4%), and Solifugae (4%). Observed to crack crested francolin (Francolinus sephaena) eggs by grasping the eggs in their forelimbs and throwing them backwards through the hindlimbs onto a rock or other hard surface. Small vertebrates (e.g. mice or snakes) are killed with a bite through the back of the head. Large insects are generally eaten starting with the head.
Activity patterns. Diurnal. Groupssleep together overnight in subterranean dens (usually termite mounds), emerging in the early morning and returning to the den before sunset. During the day, the group forages together, often resting around midday. Their repertoire of behaviors includes foraging, resting, vigilance (including standing upright), self and allogrooming, social play, scent marking, and vocalization.
Movements, Home range and Social organization. Lives in cohesive groups. Group size averages 8-9 (range = 2-21) in the Serengeti ( Tanzania), and 12-3 (range = 2-32) in the Taru Desert ( Kenya). Group members forage and sleep together, and share a home range. Termite mounds (Macrotermes and Odontotermes species) and rock crevices are commonly used as subterranean dens for sleeping at night and for shade and protection during the day. Up to 200 termitaria are available within a territory, and groups favor areas with high termitaria density. Groups generally occupy a different den every night, but use a den for longer periods when babysitting pups. Mean home range size varies from 0-27 to 0-96 km? and mean population density ranges from 3-9 to 30-9 individuals/km?®. Daily foraging distances of up to 1 km have been recorded. Larger groups travel farther than smaller groups, but reduce foraging distance when travelling with small pups. Home ranges are defended. When two groups meet, the smaller group will generally retreat, without any physical aggression, but skirmishes can occur. Groups are highly social, with heterosexual mutual grooming common. Groups contain adult males and females and young of the dominant breeding pair. There is no consistent sex ratio bias amongst adults or pups. Intragroup aggression is rare, but there is an age-related dominance hierarchy in males and females. The dominant female dominates all other group members in access to food and frequency of anal marking, and can displace others from a foraging site. The male dominance hierarchy becomes obvious during estrus, when males compete for access to females. Subordinates exhibit a submissive crouching stance on approach of a dominant. Group members cooperate in rearing young, repelling predators, and rescuing group members from predators. They communicate vocally. Short nasal “peeps”, emitted every few seconds, serve to maintain group cohesion while foraging. Lead or “moving out” calls, given by the dominant female,elicit the group to follow. Shrill “tsiii” war cries are used to alert group members to a rival group and makes the group bunch and charge; a standard deployment has the dominant male leading and the dominant female at the rear. Alarm calls convey information on predator type and urgency. Repeated “tchee” alarm calls warn the group of a predator, and a close approach of a predator is signalled with an alarm “chitter”, as they run to cover. Alarm calls are shorter and higher in pitch, the more immediate the danger. Group members, principally subordinate males, take turns standing guard, and give a “watchman’s song” to inform the group that they are on duty. Guards use posts (elevated objects). Group members follow a predictable rota of guard duty. Common Dwarf Mongooses are known to form mutualistic associations with hornbills (Zockus flavirostris and T. erythrorhynchus), which prey upon disturbed invertebrates. The mongooses benefit from the hornbills’ alarm calls for raptors. Interestingly, the hornbills give alarm calls to raptor species that prey on mongooses, but not hornbills. Olfactory communication is also used in intraand inter-group communication. Group members scent-mark each other and the den site with their anal or cheek glands. This marking is often done communally, particularly after intergroup encounters. Male anal gland secretions contain vitamin E (absent in female secretions), suggesting they play a sex-specific role.
Breeding. In seasonal climates, births are restricted to the wetter months, which is likely to be correlated with invertebrate prey availability. Dominant females can produce up to four litters per year. The age offirst conception for femalesis rarely under two years. Estrus in a group is synchronized and occurs for one to seven days. Estrus can occur within two to four weeks of parturition, enabling females to conceive and gestate while suckling the current litter of pups. During estrus, males compete for access to females and females solicit copulation from males. Early in the dominant female’s estrous cycle, the dominant male guards her, maintaining exclusive proximity and copulation access and aggressively repelling subordinate males, who attempt to sneak copulations. Later in estrus, the dominant male will mate with subordinate females. The dominant female then mates other males. Almost all individuals mate, virtually everyday during estrus. However, in spite of the fact that all group members copulate, the Common Dwarf Mongoose is a classic example of a species exhibiting a despotic social system of high reproductive skew: dominant females produce 73% of all litters, despite being outnumbered by subordinates 1:2. Subordinate reproduction is suppressed both behaviorally and hormonally. There is no evidence of inbreeding avoidance; individuals mate randomly without regard to relatedness, even though most males and females within groups are usually closely related. The gestation period is approximately seven weeks. Litter size varies from two to six, with two to three being the most common. When subordinate females do breed, they are usually synchronized with the dominant female, giving birth on the same day. Most offspring born to subordinate females fail to survive, probably due to infanticide by the dominant female. Following birth of the communal litter, pups are kept in the subterranean den until they are approximately three to four weeks old. During this period, one or more individuals (usually subordinate females) will remain at the den to “babysit” the pups while the group forages (the babysitter changes daily). These babysitters guard the communal litter from predators and groom and warm the pups. Some subordinate females nurse the dominant female’s pups without giving birth themselves, lactating due to a physiological pseudopregnancy. Weaning occurs around 40-45 days. When the pups emerge from the den and begin accompanying the foraging group, adults provide care by carrying, grooming, guarding, and provisioning pups. Subordinates (mainly females) usually provide more care than the parents. Pups beg for food from adults. Provisioning involves carrying food to young and dropping or leaving whole or partial prey items. There appears to be an escort system, where each pup forms a one-to-one association with an adult (its escort) that it closely follows and who feeds it, similar to the system seen in the Banded Mongoose. Pup survival is higher in groups with more helpers, principally because efficient vigilance reduces predation (of both adults and pups). With its small bodysize, open habitat, and diurnal lifestyle the Common Dwarf Mongoose is vulnerable to a variety of predators. Annual survival rate of emergent pups is 0-41 and adult annual survival rate is between 0-68 and 0-74. Pup predation is likely driven by snakes (e.g. cobra), monitor lizards, larger mongoose species (Banded Mongoose and Egyptian Mongoose), and raptors, in particular the eastern chantinggoshawk (Melierax poliopterus) and brown snake eagle (Circaetus cinerus). Predation is 260% higher in smaller groups, with guards suffering the highest predation rate. In the wild, males can live up to ten years and females 14 years. In captivity, an individual is recorded to have lived for over twelve years. Invalid care has been recorded, where the group remains in proximity to and provisions a sick or injured adult. Males and females commonly transfer between groups voluntarily or via takeovers. Females are more likely to remain in their natal group than males. Voluntary dispersers are usually young adults, who increase their probability of attaining a dominant breeding position via emigration. Single-sex and mixed-sex transient groups also occur. In contrast to the Banded Mongoose and Meerkat, emigration from groups does not appear to involve intra-group aggression (excluding takeovers).
Status and Conservation. Not CITES listed. Classified as Least Concern in The [UCN Red List. A widely distributed species that can occur at high densities. Unlikely to become threatened in the foreseeable future.
Bibliography. Beynon & Rasa (1989), Caro & Stoner (2003), Creel (1996, 2001, In press), Creel & Waser (1991, 1994, 1997), Creel, Creel et al. (1992), Creel, Monfort, Creel et al. (1995), Creel, Monfort, Wildt & Waser (1991), Creel, Wildt & Monfort (1993), Deckeret al. (1992), Estes (1991), Hiscocks & Perrin (1991a, 1991b), Keane, Creel & Waser (1996), Keane, Waser et al. (1994), Kingdon (1971-1982, 1997), Messeri (1983), Pilsworth (1977), Rasa (1973a, 1973b, 1976, 1977a, 1977b, 1979, 1983a, 1983b, 1984, 1985, 1986a, 1986b, 1987a, 1987b, 1989a, 1989b, 1994), Rood (1978, 1980, 1983a, 1986, 1987, 1990), Skinner & Chimimba (2005), Waser et al. (1995), Wozencraft (2005).
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