Showing papers by "Martha M. Robbins published in 2006"

Feeding ecology in apes and other primates : ecological, physical, and behavioral aspects

Abstract: Preface Introduction: Primate feeding ecology: an integrative approach Martha M. Robbins and Gottfried Hohmann Part I. Field Studies: Introduction Peter S. Rodman 1. Variability of the feeding ecology of eastern gorillas Martha M. Robbins, John Bosco Nkurunungi and Alastair McNeilage 2. Sympatric western gorilla and mangabey diet: reexamination of ape and monkey foraging strategies Diane M. Doran-Sheehy, Natasha F. Shah and Lisa A. Heimbauer 3. Effects of fruit scarcity on foraging strategies of sympatric gorillas and chimpanzees Juichi Yamagiwa and Augustin Kanyunyi Basabose 4. Chimpanzee feeding ecology and comparisons with sympatric gorillas in the Goualougo Triangle, Republic of Congo David Morgan and Crickette Sanz 5. Frugivory and gregariousness of Salonga bonobos and Gashaka chimpanzees: the abundance and nutritional quality of fruit Gottfried Hohmann, Andrew Fowler, Volker Sommer and Sylvia Ortmann 6. Feeding ecology of savanna chimpanzees (Pan troglodytes verus) at Fongoli, Senegal Jill D. Pruetz 7. Food choice in Tai chimpanzees: are cultural differences present? Christophe Boesch, Zoro Bertin Gone Bi, Dean Anderson and Daniel Stahl 8. The effects of food size, rarity, and processing complexity on white-faced capuchins' visual attention to foraging conspecifics Susan Perry and Juan Carlos Ordonez Jimenez Part II. Testing Theories: Introduction Richard W. Wrangham 9. Primate foraging adaptations: two research strategies Stuart A. Altmann 10. The predictive power of socioecological models: a reconsideration of resource characteristics, agonism, and dominance hierarchies Andreas Koenig and Carola Borries 11. Hunger and aggression in capuchin monkeys Charles Janson and Erin Vogel 12. How does food availability limit the population density of white-bearded gibbons? Andrew J. Marshall and Mark Leighton 13. Influence of fruit availability on Sumatran orangutan sociality and reproduction Serge A. Wich, Martine L. Geurts, Tatang Mitra Setia and Sri Suci Utami-Atmoko 14. Central place provisioning: the Hadza as an example Frank W. Marlowe Part III. Analyzing nutritional ecology: Introduction Katharine Milton 15. Estimating the quality and composition of wild animal diets - a critical survey of methods Sylvia Ortmann, Brenda J. Bradley, Caroline Stolter and Joerg U. Ganzhorn 16. The possible application of novel marker methods for estimating dietary intake and nutritive value in primates Robert W. Mayes 17. Energy intake by wild chimpanzees and orangutans: methodological considerations and a preliminary comparison Nancy Lou Conklin-Brittain, Cheryl D. Knott and Richard W. Wrangham 18. The role of sugar in diet selection in redtail and red colobus monkeys Lisa Danish, Colin A. Chapman, Mary Beth Hall, Karyn D. Rode and Cedric O'Driscoll Worman 19. Primate sensory systems and foraging behavior Nathaniel J. Dominy, Peter W. Lucas and Nur Supardi Noor.

Age-related patterns of reproductive success among female mountain gorillas

Abstract: A key goal of life history theory is to explain the effects of age and parity on the reproductive success of iteroparous organisms. Age-related patterns may be influenced by changes in maternal experience or physical condition, and they may reflect maternal investment trade-offs between current versus future reproduction. This article examines the influences of age and parity upon the interbirth intervals (IBI), offspring survival, and birth rates of 66 female mountain gorillas in the Virunga Volcano region from 1967-2004. Fertility was relatively low for females below age 12; improved as they matured; and then declined as they aged further. Primiparous mothers had 50% higher offspring mortality and 20% longer IBI than second-time mothers, though only the difference with IBI was statistically significant. The length of subsequent IBI was positively correlated with birth order but not with the mother's age. Mountain gorillas showed no evidence of an extended postreproductive lifespan. Age-related patterns seem most likely to reflect changes in the physical condition of the mother, but more detailed studies are needed to quantify those physical differences, and to obtain behavioral evidence that would provide more direct measures of maternal investment and experience.

Census of the mountain gorilla Gorilla beringei beringei population in Bwindi Impenetrable National Park, Uganda

Abstract: Mountain gorillas Gorilla beringei beringei are Critically Endangered, with just two small populations: in Bwindi Impenetrable National Park in south-western Uganda and the nearby Virunga Volcanoes on the borders with Rwanda and Uganda. A survey of the Bwindi population was carried out in 2002 and results were compared with the previous census in 1997. Our estimate of total population size increased over that period by c. 7% to 320 individuals and the structure and distribution of the population were largely unchanged. Signs of human disturbance were more common in 2002 than 1997, and gorillas tended to be found in areas of relative low disturbance. This suggested that disturbance could be a constraint on population growth and distribution but demographic stochasticity may also be responsible for the observed level of population change over a short time period. Other potential limiting factors, including habitat availability and disease, are discussed. While conservation activities in Bwindi have probably contributed to the stability of the population, strengthening of law enforcement and continued vigilance are needed to ensure the population's long-term growth and survival.

Primate feeding ecology: An integrative approach

Abstract: No biologist would argue that ecology, “the scientific study of the interactions that determine the distribution and abundance of organisms,” is not a complex topic. Feeding ecology is a central component of a species’ biology, relating to its survival, reproduction, population dynamics, habitat requirements, and patterns of sociality. If one wants to best understand certain ecological processes, primates would not necessarily come to mind as the best organisms to study because of their long life-span and slow reproductive rates, the difficulties of getting sufficient sample sizes for statistical analysis, and the constraints on using wild primates for experiments. However, studying the feeding ecology of primates has been a major area of focus in primatological studies since field studies began because of the wide diversity of ecological niches occupied by primates, the heavy influence that ecology exerts on social behavior, and how it aids us in studying human evolution and behavior. Despite being a relatively small order, primates occupy a wide range of habitats and exhibit a huge diversity of grouping patterns and behavior. Studies of primate feeding ecology assist us in answering two main questions: Why do primates have the diets they do? Why do primates behave as they do? The aim of this book is to attempt to show the relationships among many of the aspects of the biology of primates to their environment. Over the last four decades, there have been an ever-increasing number of field studies on apes and other primates that have focused on food acquisition, food processing, habitat utilization, foraging strategies, the relationship between ecology and sociality, and related topics. These studies have revealed that feeding ecology of apes and other primates is extremely diverse and complex. Perhaps more questions have been raised than answered concerning the relationship between feeding ecology and other variables such as habitat