Cercocebus galeritus galeritus
1879
Cercocebus galeritus galeritus by
Peters
2006
C. galeritus by IUCN/SSC Primate Specialist Group
In Spanish the common
name is “mangabey crestado ventriblanco”
In Italian the common
name is “cercocebo dal berretto”
In German the common name
is “Tana-haubenmangabe”
Information From the Wild
This species has been studied since 1976, therefore more is known about their habitat, habitat preferences, population, behavior, association with other primates, etc., than any other mangabey species. The Tana River delta and floodplain are not only of conservation priority because of C. g. galeritus, but of other endemic plant and animal species as well. The Tana River habitat is part of the larger East African Coastal Forest biome. This ecoregion is a belt of lowland forests that run along the coast of eastern Africa from southern Somalia to the Mbemkuru River in southern Tanzania. Most of this ecoregion has been heavily settled by humans and only widely distributed fragments of the original forests remain. The climate is generally dry and hot (20 to 40 degrees C or 68 to 104 degrees F) and during the rainy season (mostly May –June) the annual rainfall is 400 – 500 mm (16-20 inches).
In 1976, the 169 square mile Tana River Primate Reserve was established to protect the lower Tana River riverine forests. The preserve consists mainly of patches of riparian forests extending for 16 km (10 miles) along the meandering course of the lower Tana River. The preserve is 350 km east of Nairobi and 240 km north of Mombasa. In 1991 the Conservation Viability Assessment Workshop was held. C. g. galeritus are found in small forest patches bordering 37-mile stretch of the Tana River – only 7 miles or river are within the park boundary (Kinnaird, 1995). In 1996, a 5-year World Bank/GEF project started which would have relocated families presently within the reserve. Funding was withdrawn before completion of the project, leaving responsibility for the protection of the Tana River’s remaining forests and primates to the Kenya Wildlife Service. Since that time, research has showed a dramatic and continuing reduction of the forests.
This subspecies is restricted to the Tana River delta area and in 1991 approximately 600 mangabeys are estimated to be inside the reserve and another 600 mangabeys outside (Seal, Foose). The estimated population is sub-divided into approximately 50 groups that inhabit a total land area of about 26 km2 (10 mi2). The 1994 population estimate was 1000 – 1200 individuals (IUCN). A census conducted in 2001 in 73 forest patches, found an estimated population size of 2070 individuals (Karere, et al, 2004). Like the other semi-terrestrial "forms", sexual dimorphism is marked. Adult males have a characteristic spacing call that is similar to what is described in the other C. agilis and C. galeritus subspecies. They live in the seasonally flooded gallery forest of the Tana Delta and are highly opportunistic feeders, eating more than 100 items of more than 50 species. The main part of their diet is comprised of fruits, seeds and insects, and they occasionally eat small vertebrates such as frogs and lizards.
Multi-male group size was found to be 15 to 30 individuals in 1975 (Homewood) and Marsh (1986) found group size comparable at 15 to 35 individuals. Mangabey density was estimated to be 38 individuals per km2 (Kinnaird, 1990). Besides the expected predation from felids, etc., one large male mangabey was observed to be constricted and consumed (head to tail) by a large rock python (Kinnaird, 1995). Homewood (1976) reported a discrete birth season between November and February and Kinnaird (1990) reported an estimated mean gestation of 180 days. Females attain sexual maturity between 4 and 5 years (comparable to C. chrysogaster) and the inter-birth interval is 18 to 24 months (Kinnaird, 1990). As with C. torquatus, C. chrysogaster and C. atys atys, this subspecies exhibited postconception perineal swellings that may function to confuse paternity therefore decreasing the likelihood of infants becoming the victims of infanticide by dominant males (Kinnaird, 1990). Like C. torquatus and C. chrysogaster, offspring are born with pale faces, which darken within 3 to 4 months. Natal coat is an overall gray (Kinnaird, 1990).
Description
Overall agouti hair color is a yellow to fawn-gray with a light underside (the pale underside color comes up under the chin to around the ears. Crest of hairs from the forehead is significant and black tipped. The last half of the tail is black and the top of the head is a darker fawn-gray than the body. The skin on the hands, feet and face are black. Upper eyelid areas are non-pigmented.
In Captivity - North American Region
Tana River mangabeys have not been in North America. There have been a few individuals in Europe over the last 100 years (the now-closed Belle Vue Zoo in Manchester reported a male Tana River Mangabey on their animal inventory as late as 1955). There are currently a few individuals in captivity in Africa.