Redtail monkeys are commonly found in close association with other primate species, such as red colobus, mangabeys, and blue monkeys. Redtail monkeys form an important feeding association with colobus monkeys. Colobus monkeys bite through the tough outer skins of Mondura fruits and redtail monkeys are able to eat the fruit scraps that contain ordinarily unobtainable fruit pulp (Leland and Struhsaker, 1993). They have also been observed to interact socially with other species; playing, grooming, and helping in defense from common predators.
Redtail monkeys have been observed to mate with blue monkeys, and produce fertile offspring (Leland and Struhsaker, 1993).
As in all primates, communication in this species is complex, and includes chemical, visual, auditory, and tactile components. The visual communication system consists of eyebrow raising, facial skin stretching, and head-bobbing (Estes, 1991). These signals are commonly used to warn potential predators or unwanted intruders. Vocal communication consists of birdlike chirps between members of a group (Kingdon, 1984). This form of communication is mainly used socially among members of the same unit. These associated individuals may also identify one another by nose-to-nose greeting, in which two individuals press their muzzles together. After this greeting they will commonly practice reciprocal social grooming or play (Estes, 1991).
Communication Channels: visual ; tactile ; acoustic ; chemical
Perception Channels: visual ; tactile ; acoustic ; chemical
Although redtail monkey populations are currently healthy, there is some concern about their future status. As is the case with many rainforest dwelling animals, the threat of habitat loss by deforestation is a major concern. Since C. ascanius inhabits a relatively small area on the African continent, loss of habitat could be detrimental for the future of this primate species.
Redtail monkeys are also threatened by predation. They are potential prey for chimpanzees, crowned hawk-eagles, wild cats, and humans (Kingdon, 1984; Leland and Struhsaker, 1993).
Redtail monkey populations are depleted by distraught farmers that view them as pests and shoot them on sight (Leland and Struhsaker, 1993).
US Federal List: no special status
CITES: appendix ii
IUCN Red List of Threatened Species: least concern
Cercopithecus ascanius regularly practices crop raiding of nearby agricultural gardens containing maize, banana, millet, bean, pumpkin, pineapple, or passion fruit crops (Kingdon, 1984). In regions of low productivity this behavior has become a serious problem for neighboring human villages.
Redtail monkeys are also one of the major carriers of yellow fever in Africa (Kingdon, 1984). When the monkeys venture into human villages to raid their crops, there is a greater chance that an infected individual could spread this disease to the villagers.
Negative Impacts: injures humans (causes disease in humans ); crop pest
Redtail monkeys have been instrumental in the regeneration of Strychnos mitis, a tree species found in the Kibale Forest. Redtail monkeys feed heavily on the fruit of this tree. As they eat the fruit, they spit the intact seeds, which fall to the rainforest floor where the seeds can successfully germinate. This method of seed sowing produces more saplings annually than the fruit would normally produce without the help of redtail monkeys (Lambert 1995).
Redtail monkeys have also been useful as laboratory animals in studies on various viral diseases (Kingdon 1984).
Because these monkeys are frugivorous, and can transport fruits in their cheek pouches, it is likely that they play some role in seed dispersal. In addition, as a prey species, they probably have some effect on predator populations.
Ecosystem Impact: disperses seeds
Redtail monkeys are primarily frugivorous, but supplement their diet with leaves, insects, flowers, buds, and gum (Torstar Books, 1984; Chapman and Chapman, 2000).
It is common for adults to store fruit in their large cheek pouches in order to take their meal to an area free from the threat of theft by other monkeys (Torstar Books, 1984).
Animal Foods: insects
Plant Foods: leaves; fruit; flowers; sap or other plant fluids
Primary Diet: herbivore (Frugivore )
Redtail monkeys (Cercopithecus ascanius) are found in Africa from the Central African Republic eastwards through Kenya and south into Angola and Zambia. Populations are most dense in Uganda.
Biogeographic Regions: ethiopian (Native )
Redtail monkeys can live in a rather large variety of habitats. They are mainly found in the middle canopy of tropical rain forest habitats. However, they have also been observed in swamp forests, secondary forests, riverine gallery forest, and other woodlands (Smuts et al. 1987).
Habitat Regions: tropical ; terrestrial
Terrestrial Biomes: forest ; rainforest
Although data are not available for this species, other members of the genus Cercopithecus are known to live in captivity for more than 30 years. It is likely that C. ascanius is similar to other members of the genus in lifespan. Lifespan in the wild is likely to be somewhat shorter than it is in captivity.
Average lifespan
Status: wild: 30 years.
Average lifespan
Sex: female
Status: captivity: 25.9 years.
Average lifespan
Sex: female
Status: captivity: 28.3 years.
This relatively small primate exhibits some sexual dimorphism in weight and body length. Males have an average mass of 4.1 kg and a length of approximately 46 cm. Redtail monkey females, in contrast, average 2.9 kg in mass and about 38 cm in length (Torstar Books 1984; Smuts et al. 1987).
Other than size differences, males and females of this species are very similar. The recognizable markings of adult redtail monkeys include a black face, bluish skin around the eyes, a white spot on the nose, and white cheek fur. The name 'redtail' comes from the chestnut-colored fur on the underside of the tail. The rest of the body is covered with a speckled brown coat and gray or black limbs, depending on the subspecies (Torstar Books 1984).
Redtail monkey infants have woolly gray fur at birth. Although they are born with a visible nose spot, young redtail monkeys have a brown tail and no cheek whiskers. As they mature, their markings begins to resemble those of adults (Kingdon, 1984).
Range mass: 2 to 6 kg.
Average mass: males: 4.1 kg; females: 2.9 kg.
Average length: males: 46 cm; females 38 cm.
Other Physical Features: endothermic ; homoiothermic; bilateral symmetry
Sexual Dimorphism: male larger
Cercopithecus ascanius is potential prey for chimpanzees, crowned hawk-eagles, wild cats, and humans (Kingdon, 1984; Leland and Struhsaker, 1993). It is also likely that these monkeys fall victim to the same predators that trouble other small, arboreal primates in African forests. These include leopards, snakes, and a variety of avian predators.
Known Predators:
Cercopithecus ascanius displays a polygynous-promiscuous mating system (Cords et al., 1984). This type of mating characterizes populations in which one male mates promiscuously with the females of the group. Since females show no outward signs of receptiveness they frequently elicit matings with males from their own group or from wandering male groups through a behavior known as presenting (Estes, 1991).
Mating System: polygynous ; polygynandrous (promiscuous)
Redtail monkeys generally breed throughout the year, although the peak season is from November to February (Smuts et al., 1987). The majority of pregnancies produce a single infant.
Although data are lacking for C. ascanius, in general, species in the genus Cercopithecus have gestations ranging in duration from around 5 months to a maximun of 7 months. Newborns typically weigh around 400 g, and are entirely dependent upon the mother for transportation and nourishment (Nowak, 1999). It is reasonable to assume that C. ascanius is similar in these respects to other members of the genus.
Males generally reach sexual maturity at the age of six, females mature at four or five years of age (Smuts et al., 1987).
Breeding interval: It is likely that females are capable of producing young each year.
Breeding season: Redtail monkeys generally breed throughout the year, although the peak season is from November to February
Average number of offspring: 1.
Average gestation period: 6 months.
Range age at sexual or reproductive maturity (female): 4 to 5 years.
Average age at sexual or reproductive maturity (male): 6 years.
Key Reproductive Features: iteroparous ; year-round breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization ; viviparous
Average birth mass: 371 g.
Average gestation period: 147 days.
Average number of offspring: 1.
As in most primates, parental care is mainly the responsibility of females. Young are altricial, and must be carried for the first several weeks of life. Mothers provide food (milk) for their young, as well as transportation and grooming.
Female guenons typically have life-long associations with their kin. The dominance rank of a female within her social group will affect the dominance rank of her daughters.
Parental Investment: altricial ; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female, Protecting: Female); pre-independence (Protecting: Female); post-independence association with parents; extended period of juvenile learning; maternal position in the dominance hierarchy affects status of young
The red-tailed monkey (Cercopithecus ascanius), also known as the black-cheeked white-nosed monkey, red-tailed guenon, redtail monkey, or Schmidt's guenon, is a species of primate in the family Cercopithecidae.
It is found in Angola, Cameroon, Central African Republic, Democratic Republic of the Congo, Kenya, Rwanda, South Sudan, Tanzania, Uganda, Zambia, and possibly Burundi. The red-tailed monkey is usually black, red, or orange. Although native to this region, it has spread north and south as well as it can survive in different habitats and under different conditions. It is a distinct creature in its habitats and is gradually becoming endangered due to deforestation and over-exploitation through hunting and predation.
There are five subspecies recognized for this species:
The red-tailed monkey is named as it sounds, for its red coloration of the tail's underside as well as the bi-coloration of the tail as the reddish color increases from the base to the tip. There are other features characteristic to this mammal as well such as the white nose and cheeks in the midst of black or dark grey body fur. Red-tailed monkeys also have very large, elastic cheeks which are used in gathering food and storing it in their mouths for safety.[3]
Sizes of their bodies range between individuals as well as between the sexes as males are larger than the females. Body length ranges from 1 to 2 foot (12-24 inches), without the tail included, males being on the upper end of the scale and females being on the lower. Adult males also weigh between 7 and 10 pounds and females weigh slightly less between 6 and 8 pounds. The tail length can reach up to 35 inches long which can be twice the body length for some red-tailed monkeys. The tail helps the monkeys achieve balance.
Red-tailed monkeys communicate using different methods which are characteristic of communicating specific behaviors or things. Physical and vocal communication are used between members of social groups of these monkeys to demonstrate social dominance, submissiveness, or greeting. Vocal communication is used between members of social groups of red-tailed monkeys in which the more submissive monkey will make a soft, oscillating call to its elder. Physical communication is exhibited in nose to nose greetings where two red-tailed guenons touch their noses together. This is a sign of affection and can be followed by playful behavior. Visual communication is used as a sign of warning to others to stay away and as a defense against predators. Red-tailed monkeys practice staring or staring with their mouth open. When these monkeys implement staring, they lift their eyebrows to retract the skin on their forehead which makes the skin on the face expand backwards revealing the underneath of their eyelids. On the dark fur background, their eyelids can be seen very easily by others and understand it as a display that the red-tailed monkey is being threatened and the other species needs to stay away. Head-bobbing is another threat display in which the monkey moves its head up and down. These types of communication can be used separately or together depending on how threatened the monkey feels to its surroundings.[4] Other types of communication are used such as chemical and olfactory communication; however, not much information is available on this type of communication.
Red-tailed monkeys are primarily fructivorous, but are considered omnivorous because they will eat leaves, flowers, or insects in times where fruit is scarce. As they forage, these monkeys gather their findings in the expandable cheeks of their mouths. The pouches will hold a large amount of food where they can forage in one area and then carry their food away to another location where it is safe to consume without the threat of another stealing from them.[3]
Red-tailed monkeys are social primates that form groups that can range in size from 7 to 30 individuals. The groups consist of one dominant male and females and their offspring, male or female juveniles. Groups generally stay together through all periods of the day and through life, except for males who reach maturity. These males will leave the group they were born into and go on to form all male groups with other red-tailed monkey males or survive alone until they can replace the dominant male of a different social group.[5] The females practice allomaternal care in which the various females in a group will help take care of their own young as well as the young of other females in the group. Often, the different social groups will congregate for support from each other when food is unlimited and in abundance.[6]
Red-tailed monkeys have been observed interacting with blue monkeys, including interspecies grooming.[7][8]
Red-tailed monkeys are active in the early morning and evening which is characterized as diurnal activity. They act as important seed dispersers as they collect fruit and other food items. Their dispersal is throughout the tropical forest of in East and Central Africa ranging to Kenya and many areas of the Congo. The red-tailed monkey species is categorized in recognized subspecies and these subspecies have different ranges, the subspecies C. a. schmidti having the widest distribution from Congo into countries of Kenya, Tanzania, and Uganda and the subspecies C. a. atrinasus having the smallest distribution restricted to a local habitat of Zovo, Angola.[9] They are primarily arboreal but will come to the ground. In the trees, they are very active and travel at greater speeds than being on the ground. On the ground, they travel quadrupedally, on all four legs. While they show a dominating preference for being arboreal in activity and where they choose to rest, they forage on the ground and as a result, they spend an adequate amount of their time on the forest floor as well.[10]
Like all placental mammals, red-tailed monkeys produce viviparous young. They tend to only give birth to a single young per mating season.[3] Their mating system is characterized as polygynous meaning that one male mates with multiple females and is a common sight in mammals due to advantages of the grouped social system. The most prominent and successful mating season is from the month of November extending into the month of February; however, breeding can occur throughout the course of an entire year.[6] In some studies, it has been seen that the red-tailed monkey will interbreed and hybridize with another species in its genus: the blue monkey (C. mitis). The hybrids have been seen on the terrestrial island of Gombe, Tanzania, and this hybridization could serve a vital purpose in the reproduction of both the red-tailed and blue monkey species, and quite possibly, produce a new species in the future.[11]
Conservation efforts for the red-tailed monkey are of "least concern" as listed by the IUCN Red List of Threatened Species.[2] This has been justified because this species of monkey is located at many different habitats throughout the Congo and throughout East-Central Africa. Also, the species is quite abundant in these areas and they have an average lifespan of about 28 years.[3] The red-tailed monkey is subject to predation by crowned eagles, wild cats, and occasionally, humans and chimpanzees. Despite the influence of predation on their population, no major threat to this species in terms of endangerment is posed, although some locations of their habitat suffer from deforestation and hunting pressure as well.
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: CS1 maint: multiple names: authors list (link) The red-tailed monkey (Cercopithecus ascanius), also known as the black-cheeked white-nosed monkey, red-tailed guenon, redtail monkey, or Schmidt's guenon, is a species of primate in the family Cercopithecidae.
It is found in Angola, Cameroon, Central African Republic, Democratic Republic of the Congo, Kenya, Rwanda, South Sudan, Tanzania, Uganda, Zambia, and possibly Burundi. The red-tailed monkey is usually black, red, or orange. Although native to this region, it has spread north and south as well as it can survive in different habitats and under different conditions. It is a distinct creature in its habitats and is gradually becoming endangered due to deforestation and over-exploitation through hunting and predation.