Canis simensis

Ethiopian wolf, Simien jackal, Simien fox, or Abyssinian wolf


Classification

Geographic Range

Ethiopian: The Ethiopian wolf has a very restricted range. It is found only in six or seven mountain ranges of Ethiopia. This includes the Arssi and Bale mountains of southeast Ethiopia, the Simien mountains, northeast Shoa, Gojjam, and Mt. Guna. The largest population exists in the Bale Mountains National Park with 120-160 individuals.

Physical Characteristics

Mass: 11 to 19 kg

Canis simensis is a medium-sized canid, resembling a coyote in both size and structure. It stands 60 cm high at the shoulder. The Ethiopian wolf's head and body length is around 100 cm, and its tail length is approximately 33 cm. Males are significantly larger than females. Males have a mass of 14-19 kg, while females weigh 11-14 kg. Canis simensis has long legs and an elongate muzzle. Its ears are broad, pointed, and directed forward.

Canis simensis has a bright reddish coat with white on the throat, neck, and underparts. The underside of the Ethiopian wolf's tail also is white on the basal half and black towards the posterior half. Also, the inside of the legs is white. The coat has short guard hairs with thick underfur. The underfur provides insulation at temperatures as low as -15C. Contrast between the red coat and white markings increases with age and social rank. Females generally have a paler coat than males.

The dental formula for C. simensis is 3/3 1/1 4/4 2/3. The teeth are small and widely spaced. The canines are sharply pointed and average 19 mm in length, and the carnassials are relatively small.

Natural History

Food Habits

Canis simensis is a carnivore, generally preying on rodents ranging in size from the giant mole-rat Tachyoryctes macrocephalus (900 g) to that of the common grass rats (Arvicanthis blicki, Lophuromys melanonyx; 90-120 g). In 689 feces, murid rodents accounted for 95.8% of all prey items, and 86.6% belonged to the three species listed above. When present in the hunting range, giant mole-rats are the primary component of the diet. In its absence, the common mole-rat Tachyoryctes splendens is most commonly eaten. Canis simensis also eats goslings, eggs, and young ungulates (reedbuck and mountain nyla) and occasionally scavenges carcasses. The Ethiopian wolf often caches its prey in shallow holes.

Prey is usually captured by digging it out of burrows. Areas of high prey density are patrolled by wolves walking slowly. Once prey is located, the wolf moves stealthily towards it and grabs it with its mouth after a short dash. Occasionally, the Ethiopian wolf hunts cooperatively to bring down young antelopes, lambs, and hares.

Reproduction

Once a year between October and January, the dominant female in each pack gives birth to a litter of 2-6 pups. Gestation lasts approximately 60-62 days. The female gives birth to her litter in a den she digs in open ground under a boulder or in a rocky crevice. The pups are born with their eyes closed and no teeth. They are charcoal gray with a buff patch on their chest and under areas. At about 3 weeks, the coat begins to be replaced by the normal adult coloring and the young first emerge from the den. After this time, den sites are regularly shifted, sometimes up to 1300m. It is not uncommon for a subordinate female to assist in suckling the young. In these cases, the subordinate lactating female is likely pregnant and either loses or deserts her own young for those of the dominant female.

Development of the young occurs in three stages. The first covers weeks 1-4 when the pups are completely dependent on their mother for milk. The second occurs from week 5-10 from when the pups' milk diet is supplemented by solid food regurgitated from all pack members. It ends when the pups are completely weaned. Finally, from week 10 until about 6 months, the young survive almost solely on solid food provided from adult members of the pack. Adults have been seen providing food for young up to 1 year old. The Ethiopian wolf attains full adult appearance at 2 years of age, and both sexes are sexually mature during their second year. Data on life expectancy is inadequate, but C. simensis is likely to live 8-9 years in the wild.

Behavior

Although it primarily does its hunting alone, C. simensis is a social animal, forming packs of 3-13 individuals (mean 6). Packs congregate for social greetings and border patrols at dawn, midday, and evening, but forage individually during the rest of the day. The Ethiopian wolf is diurnal and sleeps in the open during night, alone or in groups. Pack structure is hierarchical and well defined by dominant and submissive displays as seen with other canids. Each sex has a dominance rank with shifts occurring in males occasionally but not in females. Play-fighting among pups in the first few weeks begins to establish rank between siblings.

For Ethiopian wolves, dispersal from their native packs is limited due to habitat saturation. Males generally remain in their natal pack, and a small number of females disperse in their second or third year. To combat this high potential for inbreeding inside the closely related pack, matings outside the pack occur frequently. Copulation outside the pack occurs with males of all rank, but those within the pack occur only between the dominant male and female. While copulation between males and subordinate females does occur, pups that may arise from this union rarely survive.

Prior to copulation, the dominant female increases her rate of scent marking, play soliciting, food begging towards the dominant male, and aggressive behavior towards subordinate females. Ethiopian wolves mate over a period of 3-5 days, involving a copulation tie that lasts up to 15 minutes.

Ethiopian wolf packs are territorial. C. simensis travels in packs to patrol its territory. Packs maintain the boundaries of their territories by scent marking and vocalization. Home ranges of packs are small for a canid of its size. The typical home range is 4-15 square kilometers with an average wolf density of 1/square kilometer. Skirmishes between neighboring packs are frequent.

Canis simensis makes several types of vocalization. Alarm calls are emitted at the sight or scent of man, dogs, or unfamiliar wolves. They start with a "huff" and are followed by a series of "yelps" and "barks." Greeting calls consist of "growls" of threat, high-frequency "whines" of submission, and "group yip-howls" given at reunion of pack members. Also, "lone howls" or "group howls" can be heard 5 km away and are used for long distance communication.

Habitat

Canis simensis is found in Afro-alpine grasslands and heathlands where vegetation is less than 0.25 m high. It lives at altitudes of 3000-4400 m.

Other Comments

A recent genetic study suggests that the C. simensis is more closely related to gray wolves and coyotes than any other African canid (jackals, foxes, wild dogs). It is hypothesized that C. simensis is an evolutionary remnant of a past invasion of North Africa by gray wolf-life ancestors.