Life History of Cercopithecus mitis stuhlmanni in the Kakamega Forest, Kenya

Abstract

Comparative data from wild populations are necessary to understand the evolution of primate life history strategies. We present demographic data from a 29-yr longitudinal study of 8 groups of individually recognized wild blue monkeys (Cercopithecus mitis stuhlmanni). We provide estimates of life history variables and a life table for females. Most females had their first infant at 7 yr. The mean interbirth interval was 28 mo, and decreased from 31 to 18 mo if the first infant died within a year. Interbirth intervals did not differ according to infant sex, but females had longer intervals after their first vs. subsequent births. Infant mortality was 23% and did not differ strongly by sex or mother's parity. Maximal female lifespan was 32.5-34.5 yr. Across the lifespan, both survivorship and fecundity showed typical primate patterns. Survivorship was lowest in infants, leveled off among juveniles, and then decreased gradually with increasing age in later life. Fecundity was highest among young females and decreased among older females. Births were seasonal, with 64% occurring within 3 mo at the end of the dry season and beginning of the wet season. Survival to 12 mo was higher for infants born during drier months. Birth season timing is plausibly related to thermoregulation of infants, weanling foods, or maternal energy demand. Blue monkeys are a forest-dependent species with a very slow life history and relatively low immature and adult mortality rates compared to closely related guenons living in open habitats. Even among cercopithecines as a whole, they appear to have an exceptionally slow life history relative to body size. Differences in life history "speed" between blue monkeys and their close relatives Int

Determinants of Reproductive Performance Among Female Gray-Cheeked Mangabeys (Lophocebus albigena) in Kibale National Park, Uganda

“…1 yr. Shortened interbirth intervals after the deaths of infants, through infanticide or other causes, have also been found in captive gray-cheeked mangabeys (Deputte 1991) as well as in several other primate species, including Sanje mangabeys (Cercocebus sanjei: Fernandez et al 2014) and captive golden-bellied mangabeys (C. agilis: Walker et al 2004), Hanuman langurs (Borries and Koening 2000), chacma baboons (Cheney et al 2004), and blue monkeys (Cercopithecus mitis: Cords and Chowdhury 2010;Cords and Fuller 2010). This suggests that infanticide could be an effective reproductive strategy for the male gray-cheeked mangabeys of Kibale and may in part explain aggression toward infants by immigrant males (Arlet et al 2008).…”

Seasonal Energetic Stress in a Tropical Forest Primate: Proximate Causes and Evolutionary Implications

“…Females in this population give birth primarily between January and March [18], a period that overlaps with a seasonal peak in fruit availability (January/February; Cords, unpublished data). A study on infant development in this population showed that infants markedly decrease daytime suckling and contact time with the mother after the third month of life, and move about largely independently by the age of six months [67].…”

“…Rain falls seasonally, with the dry season typically spanning December to March, and a shorter period of low rainfall in June/July [66]. Several groups of blue monkeys have been observed since 1979 [18].…”

“…), the ability to rely on fallback foods to meet energetic demands has not eliminated seasonal constraints on reproduction, even when living in a tropical moist rainforest [12], [13]. Suggested proximate constraints limiting reproduction to certain times of year among primates include energetic stress in pregnant and lactating females [14]–[16], limited availability of weanling food [13], [17], temperature stress in newborn infants [18]–[20], or a combination of these and other factors [12].…”

“…So far, only few studies have explicitly investigated the relationship between environmental stressors and reproductive strategies in wild primates [28], [45]–[47], and studies on female primates are particularly rare [11], [48]. Here, our primary goal was to investigate how temporal variation in physiological stress responses may help us understand the proximate mechanisms that mediate female reproductive strategies in a tropical forest monkey, using as an example a well-studied population of blue monkeys ( Cercopithecus mitis stuhlmanni ) in western Kenya [18].…”