The Ethiopian wolf (Canis simensis) is a canid native to the Ethiopian Highlands. It is similar to the coyote in size and build, and is distinguished by its long and narrow skull, and its red and white fur. Unlike most large canids, which are widespread, generalist feeders, the Ethiopian wolf is a highly specialised feeder of Afroalpine rodents with very specific habitat requirements. It is one of the world's rarest canids, and Africa's most endangered carnivore.
The species' current range is limited to seven isolated mountain ranges at altitudes of 3,000–4,500 m, with the overall adult population estimated at 360-440 individuals in 2011, more than half of them in the Bale Mountains.
The Ethiopian wolf is listed as endangered by the IUCN, on account of its small numbers and fragmented range. Threats include increasing pressure from expanding human populations, resulting in habitat degradation through overgrazing, and disease transference from free-ranging dogs. Its conservation is headed by Oxford University's Ethiopian Wolf Conservation Programme, which seeks to protect wolves through vaccination and community outreach programs.
The Ethiopian wolf is similar in size and build to North America's coyote; it is larger than the golden, black-backed, and side-striped jackals, and has relatively longer legs. Its skull is very flat, with a long facial region accounting for 58% of the skull's total length. The ears are broad, pointed, and directed forward. The teeth, particularly the premolars, are small and widely spaced. The canine teeth measure 14–22 mm in length, while the carnassials are relatively small. The Ethiopian wolf has eight mammae, of which only six are functional. The front paws have five toes, including a dewclaw, while the hind paws have four. As is typical in the genus Canis, males are larger than females, having 20% greater body mass. Adults measure 841–1,012 mm (33.1–39.8 in) in body length, and 530–620 mm (21–24 in) in height. Adult males weigh 14.2–19.3 kg (31–43 lb), while females weigh 11.2–14.15 kg (24.7–31.2 lb).
The Ethiopian wolf has short guard hairs and thick underfur, which provides protection at temperatures as low as −15 °C. Its overall colour is ochre to rusty red, with dense whitish to pale ginger underfur. The fur of the throat, chest and underparts is white, with a distinct white band occurring around the sides of the neck. There is a sharp boundary between the red coat and white marks. The ears are thickly furred on the edges, though naked on the inside. The naked borders of the lips, the gums and palate are black. The lips, a small spot on the cheeks and an ascending crescent below the eyes are white. The thickly furred tail is white underneath, and has a black tip, though, unlike most other canids, there is no dark patch marking the supracaudal gland. It moults during the wet season (August–October), and there is no evident seasonal variation in coat colour, though the contrast between the red coat and white markings increases with age and social rank. Females tend to have paler coats than males. During the breeding season, the female's coat turns yellow, becomes woolier, and the tail turns brownish, losing much of its hair.
Animals resulting from Ethiopian wolf-dog hybridisation tend to be more heavily built than pure wolves, and have shorter muzzles and different coat patterns.
The Ethiopian wolf is a social animal, which lives in family groups containing up to 20 individuals older than one year, though packs of six wolves are more common. Packs are formed by dispersing males and a few females, which with the exception of the breeding female, are reproductively suppressed. Each pack has a well-established hierarchy, with dominance and subordination displays being common. Upon dying, a breeding female can be replaced by a resident daughter, though this increases the risk of inbreeding. Such a risk is sometimes circumvented by multiple paternity and extra-pack matings. The dispersal of wolves from their packs is largely restricted by the scarcity of unoccupied habitat.
These packs live in communal territories, which encompass 6 km2 (2.3 sq mi) of land on average. In areas with little food, the species lives in pairs, sometimes accompanied by pups, and defends larger territories averaging 13.4 km2 (5.2 sq mi). In the absence of disease, Ethiopian wolf territories are largely stable, but packs can expand whenever the opportunity arises, such as when another pack disappears. The size of each territory correlates with the abundance of rodents, the number of wolves in a pack, and the survival of pups. Ethiopian wolves rest together in the open at night, and congregate for greetings and border patrols at dawn, noon, and evening. They may shelter from rain under overhanging rocks and behind boulders. The species never sleeps in dens, and only uses them for nursing pups. When patrolling their territories, Ethiopian wolves regularly scent-mark, and interact aggressively and vocally with other packs. Such confrontations typically end with the retreat of the smaller group.
The mating season usually takes place between August and November. Courtship involves the breeding male following the female closely. The breeding female only accepts the advances of the breeding male, or males from other packs. The gestation period is 60–62 days, with pups being born between October and December. Pups are born toothless and with their eyes closed, and are covered in a charcoal-grey coat with a buff patch on the chest and abdomen. Litters consist of two to six pups, which emerge from their den after three weeks, when the dark coat is gradually replaced with the adult colouration. By the age of five weeks, the pups feed on a combination of milk and solid food, and become completely weaned off milk at the age of 10 weeks to six months. All members of the pack contribute to protecting and feeding the pups, with subordinate females sometimes assisting the dominant female by suckling them. Full growth and sexual maturity are attained at the age of two years.
Most females disperse from their natal pack at about two years of age, and some become “floaters” that may successfully immigrate into existing packs. Breeding pairs are most often unrelated to each other, suggesting that female-biased dispersal reduces inbreeding. Inbreeding is ordinarily avoided because it leads to a reduction in progeny fitness (inbreeding depression) due largely to the homozygous expression of deleterious recessive alleles.
The Ethiopian wolf is restricted to isolated pockets of Afroalpine grasslands and heathlands inhabited by Afroalpine rodents. Its ideal habitat extends from above the tree line around 3,200 to 4,500 m, with some wolves inhabiting the Bale Mountains being present in montane grasslands at 3,000 m. Although specimens were collected in Gojjam and northwestern Shoa at 2,500 m in the early 20th century, no recent records exist of the species occurring below 3,000 m. In modern times, subsistence agriculture, which extends up to 3,700 m, has largely restricted the species to the highest peaks.
The Ethiopian wolf uses all Afroalpine habitats, but has a preference for open areas containing short herbaceous and grassland communities inhabited by rodents, which are most abundant along flat or gently sloping areas with poor drainage and deep soils. Prime wolf habitat in the Bale Mountains consists of short Alchemilla herbs and grasses, with low vegetation cover. Other favourable habitats consist of tussock grasslands, high-altitude scrubs rich in Helichrysum, and short grasslands growing in shallow soils. In its northern range, the wolf's habitat is composed of plant communities characterised by a matrix of Festuca tussocks, Euryops bushes, and giant lobelias, all of which are favoured by the wolf's rodent prey. Although marginal in importance, the ericaceous moorlands at 3,200-3,600 m in Simien may provide a refuge for wolves in highly disturbed areas.
In the Bale Mountains, the Ethiopian wolf's primary prey are big-headed mole-rats, though it also feeds on grass rats, black-clawed brush-furred rats, and highland hares. Other secondary prey species include vlei rats, yellow-spotted brush-furred rats, and occasionally goslings and eggs. Ethiopian wolves have twice been observed to feed on rock hyraxes and mountain nyala calves. In areas where the big-headed mole-rat is absent, the smaller East African mole-rat is targeted. In the Simien Mountains, the Ethiopian wolf preys on Abyssinian grass rats. Undigested sedge leaves have occasionally been found in Ethiopian wolf stomachs. The sedge possibly is ingested for roughage or for parasite control. The species may scavenge on carcasses, but is usually displaced by dogs and African golden wolves. It typically poses no threat to livestock, with farmers often leaving herds in wolf-inhabited areas unattended.
Rabies outbreaks, stemming from infected dogs, have killed many Ethiopian wolves over the 1990s and 2000s. Two well-documented outbreaks in Bale, one in 1991 and another in 2008-2009, resulted in the die-off or disappearance of 75% of known animals. Both incidents prompted reactive vaccinations in 2003 and 2008-2009, respectively. Canine distemper is not necessarily fatal to wolves, though a recent increase in infection has occurred, with outbreaks of canine distemper having been detected in 2005-2006 in Bale and in 2010 across subpopulations.
During the 1990s, wolf populations in Gosh Meda and Guguftu went extinct. In both cases, the extent of Afroalpine habitat above the limit of agriculture had been reduced to less than 20 km2. The EWCP team confirmed the extinction of a wolf population in Mt. Guna in 2011, whose numbers had been in single figures for several years. Habitat loss in the Ethiopian highlands is directly linked to agricultural expansion into Afroalpine areas. In the northern highlands, human density is the among the highest in Africa, with 300 people per km2 in some localities, with almost all areas below 3,700 m having been converted into barley fields. Suitable areas of land below this limit are under some level of protection, such as Guassa-Menz and the Denkoro Reserve, or within the southern highlands, such as the Arsi and Bale Mountains. The most vulnerable wolf populations to habitat loss are those within relatively low-lying Afroalpine ranges, such as those in Aboi Gara and Delanta in North Wollo.
Some Ethiopian wolf populations, particularly those in North Wollo, show signs of high fragmentation, which is likely to increase with current rates of human expansion. The dangers posed by fragmentation include increased contact with humans, dogs, and livestock, and further risk of isolation and inbreeding in wolf populations. Although no evidence of inbreeding depression or reduced fitness exists, the extremely small wolf population sizes, particularly those north of the Rift Valley, raise concerns among conservationists. Elsewhere, the Bale populations are fairly continuous, while those in Simien can still interbreed through habitat corridors.
Although wolves in Bale have learned to use cattle to conceal their presence when hunting for rodents, the level of grazing in the area can adversely affect the vegetation available for the wolves' prey. Although no declines in wolf populations related to overgrazing have occurred, high grazing intensities are known to lead to soil erosion and vegetation deterioration in Afroalpine areas such as Delanta and Simien.
Direct killings of wolves were more frequent during the Ethiopian Civil War, when firearms were more available. The extinction of wolves in Mt. Choqa was likely due to persecution. Although people living close to wolves in modern times believe that wolf populations are recovering, negative attitudes towards the species persist due to livestock predation. Wolves were largely unmolested by humans in Bale, as they were not considered threats to sheep and goats. However, they are perceived as threats to livestock elsewhere, with cases of retaliatory killings occurring in the Arsi Mountains. The Ethiopian wolf has not been recorded to be exploited for its fur, though in one case, wolf hides were used as saddle pads. It was once hunted by sportsmen, though this is now illegal. Vehicle collisions killed at least four wolves in the Sanetti Plateau since 1988, while two others were left with permanent limps. Similar accidents are a risk in areas where roads cut across wolf habitats, such as in Menz and Arsi.