Otocyon megalotis
Creators: name: Wilson, Don E.
name: Mittermeier, Russell A.
Publisher: name: Zenodo
Year: 2009
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Mammalia
Carnivora
Canidae
Otocyon
Otocyon megalotis

description: 23. Bat-eared Fox Otocyon megalotis French: Otocyon / German: Loffelhund / Spanish: Zorro orejudo Taxonomy. Canis megalotis Desmarest, 1822, Cape of Good Hope, South Africa. Included by some authors in a separate subfamily, the Otocyoninae, on account ofits atypical dentition. More recently this species was considered to have affinities with the vulpine line. Occurs in two distinct populations that are geographically separated by about 1000 km. The two populations were probably connected during the Pleistocene. Two subspecies are recognized. Subspecies and Distribution. O. m. megalotis Desmarest, 1822 — S Africa. O. m. virgatus G. S. Miller, 1909 — E Africa. Descriptive notes. Head-body 46-2—-60- 7 cm for males and 46-7-60- 7 cm for females, tail 23-34 cm for males and 27- 8-34 cm for females; weight 3-4— 4-9 kg for males and 3-2-5- 4 kg for females. A small, slight animal with slender legs, a long bushy tail and conspicuouslylarge ears. Males are often slightly heavier than females. The back of the ears, front part of the snout, face mask, front and lower part of the back legs, and the mid-dorsal part of the tail are black. A whitish band extends from across the forehead up the first three quarters of the frontal rim of the ears. Some animals have a broad dark mid-dorsal band. Beige to honey-colored fur covers the lower jaw, the throat, chest, and underparts. The body and tail fur is thick and soft on the upper parts, with a black base and white tip, giving a grizzled or gray appearance. Bat-eared Foxes have 46-50 teeth, the largest number for any non-marsupial land mammal. They are unique amongst living eutherians (odontocetes excepted) in having four to five functional lower molars, and are the only modern canids with three to four upper molars. The milk dentition is typically canid, with unreduced carnassials. In adults, the carnassial shear is lost and molars become the most bunodont, verging on zalambdodont, of any canid. Supernumerary molars yield a dentition of 13/3, C 1/1, PM 4/4, M 3-4/4-5 = 46-50. Habitat. In southern Africa prime habitat is mainly short-grass plains and areas with bare ground, but foxes are also found in open scrub vegetation and arid or semi-arid shrub land and open arid savannah. The range of Bat-eared Foxes overlaps almost completely with that of termites of the Hodotermes and Microhodotermes genera that prevail in their diet. In East Africa Bat-eared Foxes are common in open grassland and woodland boundaries, but not on short-grass plains. Those areas occupied by Bateared Foxes usually contain more harvester termite (1. mossambicus) foraging holes and dung from migratory ungulates where beetles are likely to be found. Food and Feeding. Insects are the primary food sources in open grassland and woodland edge habitats. Harvester termites and beetles are typically the most commonly consumed prey items. Diet is supplemented by orthopterans, beetle larvae, and ants. In open shrub savannahs, arachnids and fruit (consumed seasonally) may be among the more common food items. Small mammals, birds, eggs, and reptiles are eaten sporadically in southern Africa, but rarely in eastern Africa. There 1s seasonal variation in the proportion of particular taxa consumed: in the Serengeti dung beetles are the main source of food during the rainy season, when termite activity is reduced. When both beetles and termites are scarce, Bat-eared Foxes will dig up beetle larvae from the ground. Harvester termites and dung beetles are more abundant in areas inhabited by clusters of Bat-eared Fox families, and local differences in H. mossambicus density are inversely related to territory size. Although Fox water requirements may be met by the high water content of their insect prey or by berries during the summer, water is nevertheless a critical resource during lactation. Groups forage as a unit. Foraging techniques depend on prey type, but food is often located by walking slowly, nose close to the ground and ears cocked forward. Prey is detected mostly by sound and often excavated by digging. Foraging and feeding rates are higher when feeding on termite patches than on more dispersed insects. When feeding on termite patches, group members feed closely together, but when feeding on beetles, beetle larvae or grasshoppers, they can forage up to 200 m apart. Activity patterns. Changes in daily and seasonal H. mossambicus availability directly affect Bat-eared Fox activity patterns. Activity is mostly nocturnal in eastern Africa. In southern Africa, nocturnal foraging during summer gradually changes to an almost exclusively diurnal pattern in winter, in accordance with the activity changes of H. mossambicus. Diurnal foraging peaks when insect activity is highest. Bat-eared Fox groups in the Serengeti frequently patrol known Hodotermes patches in their territory after leaving the den in the evening. Movements, Home range and Social organization. In southern Africa Bat-eared Foxes live in monogamous pairs with their pups, while in eastern Africa they live in stable family groups consisting of a male and up to three closely related females with pups. Adult group size varies with the time of year, with a mean of 2-7 for southern Africa and 2-4 for eastern Africa; group size prior to pup dispersal is six. Additional females in extended family groups are usually philopatric daughters, sometimes from several generations, organized in an age-based hierarchy where all females breed. Young pups are taught to forage by the male, and social learning by pups also seemsto play a role. In the Serengeti, parents facilitate better access to H. mossambicus patches by regularly guiding the smaller and more vulnerable pups from the breeding den to “nocturnal feeding dens”. Nuclear family groups persist until cub dispersal. Home ranges vary from less than 1 km? to more than 3 km?. Home ranges overlap widely and may be clustered around harvester termite colonies. Territories are patrolled and urine-marked during part of the year. Group size determines the outcome of territorial conflicts. Territory inheritance is not uncommon in the Serengeti and neighboring groups can be closely related, with animals visiting each other from time to time. Foxes engage in frequent and extended allogrooming sessions, which increase markedly during courtship. Vigorous and extended social play is very common, including among adults after the young have dispersed. Communication is primarily visual, and often based on a variety of ear and tail positions. The unique “inverted U” position of the tail, for example,is indicative of variousstates of arousal including fear, play and alarm. Vocalizations are mostly soft and sparingly used, except when the Foxes are highly alarmed or excited during play. Breeding. Bat-eared Foxes become sexually mature at 8-9 months of age. Pair-bonding and mating occur from July to September, and involve up to ten copulations per day for several days. Copulatory ties last about four minutes, and are followed by post-copulatory play. Foxes have one litter per year. Births occur between October and December, following a gestation period of 60-75 days. Litter size ranges from 1-6, and neonates weigh 99-142 g. Dens are excavated or adapted from abandoned dens of other mammals, e.g. Spring hare, Aardvark, and even termite mounds and warthog (Phacochoerus spp.) holes. Dens can be located in clusters and may have several entrances, chambers, and tunnels. Small pups nurse inside the den and are sometimes moved between dens. They first emerge for brief periods when they are 8-12 days old. Dens are carefully maintained throughout the year and often used for generations. Parental care such as grooming, playing, and guarding against predators is mostly the responsibility of males. Female investment during lactation is high compared to other canids, and their insectivorous diet prevents mothers and/or pups from being provisioned directly. However, the high level of male parental care enables females to maximize their foraging time, compensating for the fact that their nutritional intake 1s limited to small, dispersed food items. Weaning (at 10-15 weeks) occurs after the first rains and the subsequent flush of insects. In Serengeti, the Bat-eared Fox commonly exhibits polygyny, communal breeding, and indiscriminate allosuckling. The number of pups raised averages 2-6, but in extended family units with more than one breeding female it averages 3-6. Sharing male partners enables additional breeding females to sustain the energetic costs associated with reproduction. Status and Conservation. CITES notlisted. Classified as Least Concern on The IUCNRed List. No current legal protection known. The species is common in conservation areas in southern and eastern Africa, becoming uncommon in arid areas and on farmland. Primary threats are hunting for skins, persecution as erroneously perceived predators of young lambs, and road kills. Population numbers can fluctuate from abundant to rare depending on rainfall, food availability, breeding stage and disease. Rabies and canine distemper have been reported to cause drastic population declines in some areas. Bibliography. Berry (1978), Gittleman (1989), Guilday (1962), Kieser (1995), Koop &amp; Velimirov (1982), Kuntzsch &amp; Nel (1992), Lamprecht (1979), Le Clus (1971), Maas (1993a, 1993b), Maas &amp; Macdonald (2004), Mackie (1988), Mackie &amp; Nel (1989), Malcolm (1986), Nel (1978, 1990, 1993, 1999), Nel &amp; Bester (1983), Nel &amp; Maas (2004), Nel &amp; Mackie (1990), Nel et al. (1984), Pauw (2000), Skinner &amp; Smithers (1990), Smithers (1971), Stuart (1981), Waser (1980).
description: Published as part of <i>Don E. Wilson &amp; Russell A. Mittermeier, 2009, Canidae, pp. 352-446 in Handbook of the Mammals of the World – Volume 1 Carnivores, Barcelona :Lynx Edicions</i> on pages 435-436, DOI: 10.5281/zenodo.6331155