Rungwecebus kipunji
kipunji

Rungwecebus kipunji (common name: kipunji) is endemic to Tanzania. It is found in both the Rungwe-Livingstone forest in the Southern Highlands and the Ndundulu Forest Reserve of southwest Tanzania (Davenport et al., 2006). It inhabits approximately 70 square kilometers in the Rungwe-Livingstone forest and approximately three square kilometers in the Ndundulu Forest Reserve (Davenport et al., 2006; Jones, 2005). (Davenport, et al., 2006; Jones, et al., 2005)

The Ndundulu forest is submontane, whereas the Rungwe-Livingstone forest is upper montane with temperatures dropping to –3°C or colder from May through September (Davenport, 2005; Jones et al., 2005). Rungwecebus kipunji is primarily arboreal, only occasionally descending to feed or evade intragroup conflict or predators (Davenport et al., 2006). In the Rungwe-Livingstone forest, kipunji are found at elevations ranging from 1750 to 2450 meters and in the Ndundulu Forest Reserve, they are found between 1300 and 1750 meters (Davenport, 2005; Davenport et al., 2006; Jones et al., 2005). Rungwe-Livingstone forest is severely degraded with just a narrow strip of trees connecting the forests of Mounts Rungwe and Livingstone. (Davenport, et al., 2006; Davenport, 2005; Jones, et al., 2005)

Adult males are estimated to be 85 to 90 cm in length, excluding the tail. The tail has smooth pelage, is longer than the body, and is usually curled up and backward. An average adult male is estimated to have a weight between 10 and 16 kg. Sexual dimorphism is not apparent when observing the pelage color of adults. Overall, the pelage is relatively long, which may be an adaptation to the cold temperatures of the Rungwe-Livingstone forest. The dorsum is light to medium brown in color, whereas the center of the ventrum is off-white. Half of the tail is off-white as well, on the terminal end. The lower forelimbs are dark brown to black and the hands and feet are black. One distinguishing characteristic is the long, broad crest of hair along the crown of the head. The eyes are brown, but the eyelids are black along with the rest of the face. The muzzle is relatively long with elongated cheek whiskers. Rungwecebus kipunji is distinguished from mangabeys (Cercocebus and Lophocebus) by different coloration, a crest on the crown of its head, the off-white colored tail and ventrum, and its loud distinct call, referred to as a ‘honk-bark’ (Davenport, 2005; Davenport et al., 2006; Jones et al., 2005). (Davenport, et al., 2006; Davenport, 2005; Jones, et al., 2005)

Currently, information on the reproductive behavior of R. kipunji is limited. Genital swelling has been observed, which is characteristic of other female monkeys in oestrus as a means of communicating the fertility of a female to potential mates (Davenport et al., 2006; Loy, 1987). (Davenport, et al., 2006; Loy, 1987)

Although there is limited information on kipunjis, two of their close relatives, geladas Theropithecus and baboons Papio, may share similar reproductive behaviors. Considering their close phylogenetic relationship to these species, it is likely kipunji have similar reproductive characteristics. Theropithecus and Papio average one offspring per pregnancy and twinning in general is rare among monkeys (Altmann, 1970; Nowak, 1991; Simonds, 1987; van Hooff, 1990). The gestation period in these taxa is about 180 days (van Hooff, 1990). Sexual maturity is reached around five years of age for Papio and at 3.5 years for females and eight years for males among Theropithecus (Nowak, 1991; van Hooff, 1990). (Altmann and Altmann, 1970; Nowak, 1991; Simonds, 1974; van Hooff, 1990)

A great deal of parental investment is characteristic of primates and the mother is generally the primary caregiver, so it is likely Rungwecebus kipunji shares these behaviors (McKenna, 1982; Simonds, 1974). (McKenna, 1982; Simonds, 1974)

There is no information on the approximate lifespan of R. kipunji. Although, to give an estimate of the general range of possibilities for lifespan, Papio and Theropithecus have been known to reach ages of 20 and 45 years (Nowak, 1991; van Hooff, 1990). (Nowak, 1991; van Hooff, 1990)

Rungwecebus kipunji is a social species, found in groups estimated at 30 to 36 males and females, with a maximum of two infants. There is no evidence of an animal traveling alone. To date, three groups have been found in the Ndundulu Forest Reserve and 16 groups have been found in the Rungwe-Livingstone forest. A head-shaking behavior exhibited by males has been observed just before the animal flees. Kipunji are active during the day and primarily restrict their activity to the trees, rarely coming to the ground. Kipunji seem to be shy of humans (Beckman, 2005; Davenport et al., 2006). (Beckman, 2005; Davenport, et al., 2006)

The home range of each group is estimated to be between 0.24 and 0.99 square kilometers.

Kipunji have been described as very vocal, with a unique call referred to as a ‘honk-bark’ (Beckman, 2005; Davenport, et al., 2006; Jones et al., 2005). Visual, chemical, and tactile forms of communication, such as grooming, are common among most primates, and therefore are probably used by R. kipunji as well (Simonds, 1974). (Beckman, 2005; Davenport, et al., 2006; Jones, et al., 2005; Simonds, 1974)

Rungwecebus kipunji is omnivorous, eating a variety of foods, including young and mature leaves, shoots, flowers, bark, ripe and unripe fruits, lichen, moss, invertebrates, and farm crops (e.g. maize, beans, and sweet potato) (Davenport et al., 2006). (Davenport, et al., 2006)

Crowned eagles (Stephanoaetus coronatus) are common predators and leopards (Panthera pardus) are possible predators. Rungwecebus kipunji is often hunted by humans because of their crop raiding habits and for food (Davenport et al., 2006). (Davenport, et al., 2006)

Kipunjis likely aid the reproductive success of some plants by distributing seeds via fruit consumption. It is possible that leopards and crowned eagles could be negatively impacted if kipunji were not a diet component. In the Rungwe-Livingstone forest, groups of R. kipunji have been observed in association with Angolan colobus (Colobus angolensis), and blue monkeys (Cercopithecus mitis), which can be beneficial in evading predators and improving foraging success (Davenport et al., 2006). (Davenport, et al., 2006)

Residents of the Rungwe District have been known to occasionally eat kipunji (Davenport et al., 2006). (Davenport, et al., 2006)

Kipunji are known to raid farm crops (Davenport et al., 2006). Nonhuman primates can be a disease vector, creating a potential threat to human health (Daszak et al., 2000). (Davenport, et al., 2006)

Assessment for the IUCN Red List has yet to be completed, but Rungwecebus kipunji will likely be listed as “critically endangered.” Logging, hunting/poaching, charcoal-making, and unmanaged resource extraction are all known threats to this species. The narrow Bujingijila Corridor, which links the forests of Mount Rungwe and Livingstone, is severely degraded. If no action is taken, it is likely the two forests will become separated. The population of R. kipunji in the Rungwe-Livingstone area is currently estimated to consist of 500 to 1000 individuals. The Ndundulu population is estimated at less than 500 individuals (Davenport et al., 2006). (Davenport, et al., 2006)

Until recently, Lophecebus kipunji was the name assigned to this newly discovered monkey. This changed with the publication of an article in Science (Davenport et al., 2006), calling for a new genus, Rungwecebus, which is the first new genus of living monkey described in 79 years. This taxonomic change is based on molecular and morphological data, placing kipunji genetically most closely related to Papio, but too morphologically dissimilar to be included within that genus. Although genetically similar, kipunji has a smaller body size and is more arboreal than Papio and Theropithecus. The current phylogenetic description places kipunji most closely related to Papio and Theropithecus with Lophocebus being sister to these taxa (Davenport et al., 2006). (Davenport, et al., 2006)