Volume 9 2014 ISSN 1093-8966 AFRICAN PRIMATES The Journal of the Africa Section of the IUCN SSC Primate Specialist Group Editor-in-Chief: Janette Wallis PSG Chairman: Russell A. Mittermeier PSG Deputy Chair: Anthony B. Rylands Red List Authorities: Sanjay Molur, Christoph Schwitzer, and Liz Williamson African Primates The Journal of the Africa Section of the IUCN SSC Primate Specialist Group ISSN 1093-8966 African Primates Editorial Board IUCN/SSC Primate Specialist Group Janette Wallis – Editor-in-Chief Chairman: Russell A. Mittermeier Deputy Chair: Anthony B. Rylands University of Oklahoma, Norman, OK USA Simon Bearder Vice Chair, Section on Great Apes:Liz Williamson Oxford Brookes University, Oxford, UK Vice-Chair, Section on Small Apes: Benjamin M. Rawson R. Patrick Boundja Regional Vice-Chairs – Neotropics Wildlife Conservation Society, Congo; Univ of Mass, USA Mesoamerica: Liliana Cortés-Ortiz Thomas M. Butynski Andean Countries: Erwin Palacios and Eckhard W. Heymann Sustainability Centre Eastern Africa, Nanyuki, Kenya Brazil and the Guianas: M. Cecília M. Kierulff, Fabiano Rodrigues Phillip Cronje de Melo, and Maurício Talebi Jane Goodall Institute, Mpumalanga, South Africa Regional Vice Chairs – Africa Edem A. Eniang W. Scott McGraw, David N. M. Mbora, and Janette Wallis Biodiversity Preservation Center, Calabar, Nigeria Colin Groves Regional Vice Chairs – Madagascar Christoph Schwitzer and Jonah Ratsimbazafy Australian National University, Canberra, Australia Michael A. Huffman Regional Vice Chairs – Asia Kyoto University, Inuyama, Japan China: Long Yongcheng Lynne A. Isbell South-east Asia/Indochina: Jatna Supriatna, Christian Roos, Benjamin M. Rawson, and Ramesh Boonratana University of California, Davis, CA USA South Asia: Sally Walker and Sanjay Molur Gladys Kalema-Zikusoka Conservation through Public Health, Kampala, Uganda Red List Authorities Shadrack Kamenya Sanjay Molur, Christoph Schwitzer, and Liz Williamson Jane Goodall Institute-Tanzania, Kigoma, Tanzania Inza Kone Université Félix Houphouet Boigny, Abidjan, and Centre Suisse de Recherches Scientifiques en Côte d'Ivoire Joanna E. Lambert This issue of African Primates was University of Texas at San Antonio, TX USA produced with the assistance of a grant David N. M. Mbora from The Margot Marsh Biodiversity Whittier College, Whittier, CA USA Foundation, through Conservation William Olupot International’s Nature and Livelihoods, Kampala, Uganda Primate Action Fund, and the Shirley C. Strum Interdisciplinary University of California, San Diego, CA USA Perspectives on Paul T. Telfer the Environment Wildlife Conservation Society, Brazzaville, Congo program of the Tharcisse Tukizintambara University of Oklahoma. Stony Brook University, Pretoria, South Africa Edward Wiafe Presbyterian University College, Akuapem, Ghana Dietmar Zinner German Primate Center, Göttingen, Germany Layout, design, and copy-editing:Janette Wallis IUCN SSC logo: Stephen D. Nash, 2014 Front Cover: Adult female Eastern Chimpanzee (Pan troglodytes schweinfurthii) in Budongo Forest Reserve, Uganda. Photo by Janette Wallis Printed by: University of Oklahoma Printing Services African Primates online: All volumes of African Primates are available online at www.primate-sg.org/african_primates African Primates 9:1-14 (2014)/ 1 Positional Behavior and Habitat Use of Peters’ Angola Black and White Colobus Monkey (Colobus angolensis palliatus) in Structurally Distinct Areas of the Diani Forest, Kenya Noah Thomas Dunham and W. Scott McGraw Department of Anthropology, The Ohio State University, Ohio USA Abstract: We studied the positional behavior and habitat use of adult Peters’ Angola black and white colobus monkeys (Colobus angolensis palliatus) in the Diani Forest of south coastal Kenya. Data were collected from June-August of 2012 on three groups inhabiting different forest patches characterized by varying levels of degradation. Habitat differences were quantified with regard to tree species composition, tree size, and diversity indices. Results indicate that overall stratum use differed significantly among all groups while support use of one group was significantly different from that of the others. Overall locomotor and postural behaviors were largely consistent among all habitats. Locomotion was comprised predominantly of quadrupedal walking and bounding with fewer instances of climbing and leaping. The most frequently adopted position was sitting, accounting for at least 85% of postural observations for all groups. The dramatic intergroup differences in strata and support use at the Diani site demonstrate that Colobus spp. do respond to localized structural conditions; however, that the positional repertoires were consistent across sites provide clear evidence that locomotion and posture are more constrained. Key words: primate locomotion, posture, support use, strata use, colobus monkeys INTRODUCTION Understanding how prosimians, monkeys, and and these behaviors linked to different anatomical apes move through their environments has been a complexes (postcranial anatomy) (Erikson 1963; central aim of primatology since the earliest field Ashton & Oxnard 1964; Prost 1965; Napier 1967; studies (Carpenter 1934; Ripley 1967; Walker 1969; Ripley 1967; Stern & Oxnard 1973). Most of these Richard 1970; Rose 1974; Fleagle 1976). Primates categories are still in use (Hunt et al. 1996). have evolved an extraordinary array of positional Subsequent field workers sought to identify adaptations and knowing when, where and why factors that drove intra- and inter-specific variation locomotor and postural behaviors are used in living and to establish behavioral traits associated with a animals helps illustrate the selective landscape in given anatomical complex. Fleagle and Mittermeier which postcranial anatomies evolved. Early studies (1980) were among the first to explicitly test the of positional behavior emphasized a categorical extent that positional behaviors varied as a function approach: species were assigned to locomotor groups of body size, activity pattern, substrate use, and forest based on dominant movements and postures (e.g., strata, and multiple studies have since explored how quadrupeds, brachiators, and semi-brachiators) these relationships hold in other primates (Fleagle Correspondence to: Noah Thomas Dunham, Smith Laboratory, Room 4005, 174 W. 18th Ave., Columbus, Ohio 43210 USA; Phone: +1-614-209-4533; E-mail: [email protected]. 2 / Dunham and McGraw 1980; Gebo 1987; Cant 1988; Hunt 1992, 1994; associated with quantifying habitat structures, Doran 1993; Gebo & Chapman 1995a, 1995b; Remis differences in behavioral sampling methods 1995; McGraw 1998a, 1998b, 2000; Youlatos 1999; (i.e., instantaneous vs. continuous sampling), Bitty & McGraw 2007). In the course of these studies, idiosyncrasies in defining positional categories, a host of other factors that could drive positional inter-observer error, and differences in the differences between individuals, populations, and/ behavioral flexibility of individual species (Dagosto or species were identified. These can be sorted into & Gebo 1998). In this paper, we investigate several of three categories: social (e.g., age, sex, status classes), these factors by examining the positional repertoire physiological (e.g., body size, energetic constraints) and habitat use of Peters’ Angola black and white and environmental (e.g., support availability at colobus monkeys (Colobus angolensis palliatus) different strata, support inclination, canopy height, inhabiting a habitat gradient within Kenya’s Diani tree size, liana density, forest type) (Garber 1998, Forest. The striking structural differences within 2011). In addition to demonstrating that behaviors the forest at this site provide an excellent context for vary and grade into one another, these studies examining the extent that locomotion and posture underscore the notion that positional behavior vary with habitat. reflects both ultimate (i.e., evolutionary) and We tested four null hypotheses: proximate (i.e., ecological) influences (Mayr 1961, H1: All groups will spend the majority of their time 1993; Pounds 1991). Given the latter point, one in the upper forest strata (i.e., main canopy and question that has received a good deal of attention emergent layer) as has been documented in is how much behavior varies when proximate (e.g., other black and white colobus monkey species habitat) conditions change. (McGraw 1994, 1998a; Gebo & Chapman The extent that a species’ positional repertoire 1995a; Schubert 2011). is consistent across structurally different forests H2: Given constraints imposed by their relatively is important because it impacts our ability to large body size (7.1-8.9 kg), individuals will reconstruct fossil behavior based on living utilize large supports most frequently for all species. Inferences about extinct primates rely activities (McGraw 1996; Schubert 2011). on the strength of analogies based on extant taxa H3: Locomotor frequencies will not differ (Plavcan et al. 2002), so determining the degree significantly across habitat types and arboreal that behavior is context-specific is essential. If quadrupedalism (i.e., quadrupedal walking and no modern analogy exists for a trait observed in bounding) will be the most common locomotor fossil taxa, behavioral reconstruction is virtually mode as described in other species of black and impossible (Kay 1984). Similarly, if positional white colobus monkeys (Morbeck 1979; Gebo tendencies are not consistently associated with a &