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Stephen F. Ferrari - One of the best experts on this subject based on the ideXlab platform.

  • a proposal for the common names for species of Chiropotes pitheciinae primates
    Web Science, 2012
    Co-Authors: Adrian A Barnett, Liliam P Pinto, Stephen F. Ferrari, Julio Cesar Biccamarques, Marcelo Gordo, Patricia Goncalves Guedes, Maria Aparecida Lopes, Juan C Opazo, Marcio Portcarvalho, Rodrigues Dos Santos
    Abstract:

    The common English name for the genus Chiropotes is currently bearded saki. We propose the use of “cuxiu” as the common name for Chiropotes species, arguing that this term not only has deeper cultural and historical roots, but would mesh with the common name currently in use over the vast majority of the genus range. Cuxiu (pronounced “coosh-e-oo”) would be phylogenetically and taxonomically more appropriate, and less ambiguous, than the currently used term, and remove the implied close affiliation between Pithecia and Chiropotes. Finally, as an indigenously-derived name, it would fit with the common names in use for the other two genera in the sub-family Pitheciinae (uacari, Cacajao; saki, Pithecia), both of which also have indigenous origins.

  • behavior patterns of southern bearded sakis Chiropotes satanas in the fragmented landscape of eastern brazilian amazonia
    American Journal of Primatology, 2009
    Co-Authors: Suleima Do Socorro Bastos Da Silva, Stephen F. Ferrari
    Abstract:

    The endangered but poorly studied southern bearded saki, Chiropotes satanas, faces extremes of habitat fragmentation throughout its geographic range in eastern Amazonia. This article focuses on the behavior of the members of two groups—a large one (30–34 members) in continuous forest (home range=69 ha) and a much smaller one (7 members) on a 17-ha man-made island—at the Tucurui Reservoir on the Tocantins River. Quantitative behavioral data were collected through scan and all-events sampling. Both groups were characterized by the fission–fusion pattern of social organization typical of the genus and relatively high rates of traveling and feeding, also characteristic of the genus. However, the island group spent significantly more time resting and significantly less traveling than the mainland group, presumably as a function of its much smaller home range. Despite resting more, island group members engaged in significantly less social interaction, possibly because of the much smaller size of this group (which also affected visibility), or other factors, such as nutritional stress. Affiliative associations of males were a mainstay of social behavior in both groups and interspecific associations with capuchins (Cebus apella) and squirrel monkeys (Saimiri sciureus) were relatively common, especially in the mainland group. Overall, the island group presented a relatively reduced behavioral repertoire, apparently reflecting factors such as group size and the size and quality of its home range. Am. J. Primatol. 71:1–7, 2009. © 2008 Wiley-Liss, Inc.

  • Geophagy at termitaria by bearded sakis (Chiropotes satanas) in Southeastern Brazilian Amazonia.
    American journal of primatology, 2007
    Co-Authors: Liza M. Veiga, Stephen F. Ferrari
    Abstract:

    Geophagy is rare in primates, but has been recorded in a variety of platyrrhine genera. The first observation of geophagy in bearded sakis (Chiropotes satanas) is reported here. Two bouts were recorded during long-term monitoring of a free-ranging group inhabiting a small island in a reservoir in eastern Brazilian Amazonia. On both occasions, soil was obtained systematically from a termitarium in the crown of an Eschweilera coriacea tree. Both events occurred during the late dry season. Although there is no evidence of any significant shift in foraging behavior during this period, it is possible that soil ingested provided an essential mineral supplement to a diet limited by the small size of the island. Am. J. Primatol. 69:816–820, 2007. © 2007 Wiley-Liss, Inc.

  • predation of arthropods by southern bearded sakis Chiropotes satanas in eastern brazilian amazonia
    American Journal of Primatology, 2006
    Co-Authors: Liza M. Veiga, Stephen F. Ferrari
    Abstract:

    Bearded sakis are seed predators, but are also known to consume arthropods. This is the first detailed report of arthropod predation in southern bearded sakis (Chiropotes satanas). Two groups were monitored-one in continuous forest, and one on a small island-between January 2003 and February 2004. The arthropod prey included spiders and six insect orders. Island group members spent more time foraging for arthropods (3.8% vs. 2.6% of activity time) but ingested less prey (3.7% vs. 4.6% of feeding time). Arthropods accounted for a small proportion of feeding records in most months, but there were occasional sharp peaks due to the exploitation of temporary agglomerations of insects. In November, arthropods accounted for 26.6% and 14.2% of the feeding records of the mainland and island groups, respectively. The results suggest that bearded sakis actively seek arthropods as a dietary supplement, but that they represent a minor resource during most of the year, even under conditions of intense habitat fragmentation (island group).

  • habitat use by Chiropotes satanas utahicki and syntopic platyrrhines in eastern amazonia
    American Journal of Primatology, 2000
    Co-Authors: Urbano L Bobadilla, Stephen F. Ferrari
    Abstract:

    Primates were surveyed at two sites in the Xingu-Tocantins interfluvium, in eastern Amazonia, where at least eight platyrrhines are known to occur, including the endemic Chiropotes satanas utahicki, vulnerable to extinction. Only three other forms; Alouatta belzebul belzebul, Cebus apella apella, and Saguinus midas niger; were recorded at both sites. Data on habitat use (forest type and strata) were collected in standard line transect surveys and analyzed with relation to the availability of forest types, as well as between sites and species. The smallest- (S. midas) and largest-bodied (A. belzebul) species were relatively common at the continuous forest site, where they exhibited a significant preference for primary terra firme forest. At this site, Cebus demonstrated a significant preference for liana and flooded forest in contrast with primary or secondary terra firme forests. The medium-sized Cebus and Chiropotes were more common in the isolated forest fragment (where they were also observed together frequently), but no clear habitat preferences were found at this site for any species. A. belzebul occupied significantly higher forest strata than other species, which all used relatively similar levels. C.s. utahicki was active in much lower forest strata than other bearded sakis, whereas S. midas was observed at much higher levels than at other sites in eastern Amazonia. It remains unclear whether and to what extent observed patterns are determined by differences between taxa, populations, or ecosystems, but the data indicate that C.s. utahicki is relatively tolerant of habitat disturbance.

Christopher A Shaffer - One of the best experts on this subject based on the ideXlab platform.

  • mixed species associations in cuxius genus Chiropotes
    American Journal of Primatology, 2016
    Co-Authors: Christopher A Shaffer, Adrian Barnett, Thiago H. G. Alvim, Tremaine Gregory, Fabiano De Melo, Leandro Santana Moreira, Viviane S Moura, Anderson Filo, Tatiane Cardoso, Marcio Portcarvalho
    Abstract:

    Polyspecific or mixed-species associations, where two or more species come together to forage and travel as a unit, have been reported in many primate species. These associations appear to offer a number of benefits to the species involved including increased foraging efficiency and decreased risk of predation. While several researchers have suggested that cuxius (genus Chiropotes) form mixed-species associations, previous studies have not identified the circumstances under which cuxius form associations or whether they form associations more often than would be expected by chance. Here we present data on the formation of mixed-species associations by four species of cuxius at eight different sites in Brazil, Suriname, and Guyana. We analyzed data from two of the study sites, (Biological Dynamics of Forest Fragments Project (BDFFP), Brazil and the Upper Essequibo Conservation Concession (UECC), Guyana, to assess whether associations occurred more than would be expected by chance encounters and identify the factors influencing their formation. Cuxius showed a high degree of inter-site variation in the frequency of time spent in association (ranging from 2 to 26% of observation time) and duration of associations (mean duration from 22 min to 2.5 hr). Sapajus apella was the most common association partner at most sites. At BDFFP, cuxius formed associations more frequently but not for longer duration than expected by chance. For much of the year at UECC, associations were not more frequent or longer than chance. However, during the dry season, cuxius formed associations with S. apella significantly more often and for longer duration than predicted by chance. Cuxius at UECC formed associations significantly more often when in smaller subgroups and when foraging for insects, and alarm called significantly less frequently during associations. We suggest cuxius form mixed-species associations at some sites as an adaptive strategy to decrease predation risk and/or increase foraging efficiency. Am. J. Primatol. 9999:XX–XX, 2015. © 2015 Wiley Periodicals, Inc.

  • RESEARCH ARTICLE Mixed-Species Associations in Cuxi (Genus Chiropotes)
    2015
    Co-Authors: Christopher A Shaffer, Adrian Barnett, Thiago H. G. Alvim, Tremaine Gregory, Fabiano Rodrigues De Melo, Viviane S Moura, Tatiane Cardoso, Leandro Moreira, Marcio Port-carvalho, Ricardo Rodrigues Dos Santos
    Abstract:

    Polyspecificormixed-speciesassociations,wheretwoormorespeciescometogethertoforageandtravelas a unit, have been reported in many primate species. These associations appear to offer a number ofbenefits to the species involved including increased foraging efficiency and decreased risk of predation.While several researchers have suggested that cuxius (genus Chiropotes) form mixed-speciesassociations, previous studies have not identified the circumstances under which cuxius formassociations or whether they form associations more often than would be expected by chance. Here wepresent data on the formation of mixed-species associations by four species of cuxius at eight differentsites in Brazil, Suriname, and Guyana. We analyzed data from two of the study sites, (BiologicalDynamics of Forest Fragments Project (BDFFP), Brazil and the Upper Essequibo ConservationConcession (UECC), Guyana, to assess whether associations occurred more than would be expected bychance encounters and identify the factors influencing their formation. Cuxius showeda high degree ofinter-site variation in the frequency of time spent in association (ranging from 2 to 26% of observationtime) and duration of associations (mean duration from 22min to 2.5hr). Sapajus apella was the mostcommon association partner at most sites. At BDFFP, cuxius formed associations more frequently butnot for longer duration than expected by chance. For much of the year at UECC, associations were notmore frequent or longer than chance. However, during the dry season, cuxius formed associations withS. apella significantly more often and for longer duration than predicted by chance. Cuxius at UECCformed associations significantly more often when in smaller subgroups and when foraging for insects,and alarm called significantly less frequently during associations. We suggest cuxius form mixed-species associations at some sites as an adaptive strategy to decrease predation risk and/or increaseforaging efficiency. Am. J. Primatol. © 2015 Wiley Periodicals, Inc.Key words: polyspecific association; bearded sakis; Guyana; Brazil; SurinameINTRODUCTIONPolyspecific or mixed-species associations in-volve two or more species coming together to forageand travel as a unit [Cords, 1990a]. These associa-tions occurinadiverserange oftaxa,including birds[Munn & Terborgh, 1979; Powell, 1985], ungulates[Sinclair,1985],andfish[Wolf,1985],aswellasNewWorld monkeys [Hardie & Buchanan-Smith, 1997;Norconk, 1990; Porter, 2001; Rehg, 2006; Terborgh,1983], Old World monkeys [Chapman & Chapman,2000; Cords, 1990a; N€oe & Bshary, 1997; Oates WWolters&Zuberbuhler,2003],and€lemurs [Sauther, 2002], leading researchers to

  • Activity Patterns, Intergroup Encounters, and Male Affiliation in Free-Ranging Bearded Sakis (Chiropotes sagulatus)
    International Journal of Primatology, 2013
    Co-Authors: Christopher A Shaffer
    Abstract:

    The assessment of how primates divide their daily activities is one of the foundations of primate behavioral ecology but the activity patterns and social behavior of the Pitheciines, including bearded sakis (genus Chiropotes ), are poorly understood. During a 15-mo study, I collected 560 h of data on subgrouping, activity patterns, social behavior, and intergroup encounters of a group of free-ranging Guianan bearded sakis ( Chiropotes sagulatus ) in Guyana. The study group consisted of at least 65 individuals but showed a high degree of flexibility in grouping patterns (mean group size 39 ± 10). They were highly active, spending ca. 70% of their diurnal activity budget traveling and feeding. Activity patterns were relatively consistent throughout the year, although time spent feeding correlated significantly with fruit availability. The most common social behaviors were social resting and grooming. Agonism was rare (2.56% of social behavior) but did occur in the context of intergroup encounters, with males from the same group cooperating in intergroup agonism. Bearded sakis showed a high level of within group male affiliation, with male–male partners making up 65% of grooming dyads and males having another male as their nearest-neighbor 66% of the time. These results show that bearded sakis are characterized by egalitarian male–male and male–female relationships, highly fluid group sizes, and high levels of male affiliation. Similarities in the social behavior of bearded sakis and muriquis suggest several possible explanations for male–male bonding including cooperative defense of females from other groups, kinship, and maintenance of social cohesion after subgroup coalescence.

  • Ecological Correlates of Ranging Behavior in Bearded Sakis (Chiropotes sagulatus) in a Continuous Forest in Guyana
    International Journal of Primatology, 2013
    Co-Authors: Christopher A Shaffer
    Abstract:

    Group size and the distribution and quality of food resources are among the most important determinants of primate ranging behavior. In this study, I use the framework of the ecological constraints model to assess correlates of range size of a free-ranging group of bearded sakis ( Chiropotes sagulatus ). Bearded sakis are among the widest ranging neotropical primates, yet the lack of data from continuous forest populations has made understanding the factors influencing such large ranges difficult. I collected data on ranging behavior and diet during 44 full-day follows over 15 mo. The focal group used a home range of ca . 1000 ha and had daily path lengths of 2.8–6.5 km (mean = 4.0 km). Daily path length did not significantly correlate with group size, patch quality, food availability, or the spatial distribution of feeding trees. Monthly home range size significantly positively correlated with group size and patch quality. The focal group had significantly shorter paths when ripe fruit consumption was higher and had more diverse diets, visited more food patches, and used larger monthly home ranges when they consumed a higher percentage of seeds. The results of this study, combined with other recent studies of Chiropotes in continuous forest, suggest that large home ranges (approaching 1000 ha) are characteristic of the genus. Although range size may be related to group size and food patch size, I suggest nutrient mixing and the need to balance the effects of seed secondary compounds as additional explanations for the large ranges of bearded sakis.

  • feeding ecology of northern bearded sakis Chiropotes sagulatus in guyana
    American Journal of Primatology, 2013
    Co-Authors: Christopher A Shaffer
    Abstract:

    Bearded sakis (genus Chiropotes) are among the most highly specialized primate seed predators. However, long-term studies of the genus in continuous forests, with a full community of sympatric primates, are rare. Here I present data on monthly variation in the diet of Chiropotes sagulatus from a long-term study in a continuous forest in Guyana. Bearded sakis had an extremely diverse diet, exploiting more than 175 species of plants. Consistent with their highly specialized dental morphology for seed eating, seeds made up 75% of the annual diet. Sakis exploited a wide variety of mechanically protected fruits and often exploited the same plant species for more than 3 months. They consumed a high percentage of seeds in all months and seed consumption was significantly correlated with fruit abundance. When fruit became scarcer, sakis consumed a higher percentage of non-seed food items, including insects, mature fruit, and flowers. Insects were especially important during the leanest months, making up almost 40% of feeding time. Bearded saki dietary diversity (in terms of plant species) showed little variability across months. These results confirm sakis to be highly specialized seed predators. Sakis preferentially consume seeds when they are available. However, when seeds become scarce, sakis become generalists, supplementing their diet with mature fruit, insects, and flowers. The ability of bearded sakis to consume a diversity of highly abundant plant species, fruit in several stages of maturity, and a variety of different types of resources buffers them from the detrimental effects of resource scarcity. Am. J. Primatol. 75:568-580, 2013. © 2013 Wiley Periodicals, Inc.

Vinicius D. L. R. Goulart - One of the best experts on this subject based on the ideXlab platform.

  • Medium/Long wavelength sensitive opsin diversity in Pitheciidae.
    Scientific Reports, 2017
    Co-Authors: Vinicius D. L. R. Goulart, Jean P. Boubli, Robert J. Young
    Abstract:

    New World primates feature a complex colour vision system. Most species have polymorphic colour vision where males have a dichromatic colour perception and females can be either dichromatic or trichromatic. The adaptive value of high allelic diversity of opsins, a light sensitive protein, found in primates’ eyes remains unknown. Studies revealing the allelic diversity are important as they shed light on our understanding of the adaptive value of differences in the colouration of species and their ecologies. Here we investigate the allelic types found in Pitheciidae, an understudied New World primate family, revealing the diversity of medium/long wavelength sensitive opsins both in cryptic and conspicuous species of this primate family. We found five alleles in Cacajao, six in Callicebinae (i.e. Plecturocebus, Cheracebus, and Callicebus), four in Chiropotes, and three in Pithecia, some of them reported for the first time. Both cryptic and conspicuous species in this group presented high allelic diversity.

  • medium long wavelength sensitive opsin diversity in pitheciidae
    Scientific Reports, 2017
    Co-Authors: Jean P. Boubli, Vinicius D. L. R. Goulart, Robert J. Young
    Abstract:

    New World primates feature a complex colour vision system. Most species have polymorphic colour vision where males have a dichromatic colour perception and females can be either dichromatic or trichromatic. The adaptive value of high allelic diversity of opsins, a light sensitive protein, found in primates’ eyes remains unknown. Studies revealing the allelic diversity are important as they shed light on our understanding of the adaptive value of differences in the colouration of species and their ecologies. Here we investigate the allelic types found in Pitheciidae, an understudied New World primate family, revealing the diversity of medium/long wavelength sensitive opsins both in cryptic and conspicuous species of this primate family. We found five alleles in Cacajao, six in Callicebinae (i.e. Plecturocebus, Cheracebus, and Callicebus), four in Chiropotes, and three in Pithecia, some of them reported for the first time. Both cryptic and conspicuous species in this group presented high allelic diversity.

Robert J. Young - One of the best experts on this subject based on the ideXlab platform.

  • Medium/Long wavelength sensitive opsin diversity in Pitheciidae.
    Scientific Reports, 2017
    Co-Authors: Vinicius D. L. R. Goulart, Jean P. Boubli, Robert J. Young
    Abstract:

    New World primates feature a complex colour vision system. Most species have polymorphic colour vision where males have a dichromatic colour perception and females can be either dichromatic or trichromatic. The adaptive value of high allelic diversity of opsins, a light sensitive protein, found in primates’ eyes remains unknown. Studies revealing the allelic diversity are important as they shed light on our understanding of the adaptive value of differences in the colouration of species and their ecologies. Here we investigate the allelic types found in Pitheciidae, an understudied New World primate family, revealing the diversity of medium/long wavelength sensitive opsins both in cryptic and conspicuous species of this primate family. We found five alleles in Cacajao, six in Callicebinae (i.e. Plecturocebus, Cheracebus, and Callicebus), four in Chiropotes, and three in Pithecia, some of them reported for the first time. Both cryptic and conspicuous species in this group presented high allelic diversity.

  • medium long wavelength sensitive opsin diversity in pitheciidae
    Scientific Reports, 2017
    Co-Authors: Jean P. Boubli, Vinicius D. L. R. Goulart, Robert J. Young
    Abstract:

    New World primates feature a complex colour vision system. Most species have polymorphic colour vision where males have a dichromatic colour perception and females can be either dichromatic or trichromatic. The adaptive value of high allelic diversity of opsins, a light sensitive protein, found in primates’ eyes remains unknown. Studies revealing the allelic diversity are important as they shed light on our understanding of the adaptive value of differences in the colouration of species and their ecologies. Here we investigate the allelic types found in Pitheciidae, an understudied New World primate family, revealing the diversity of medium/long wavelength sensitive opsins both in cryptic and conspicuous species of this primate family. We found five alleles in Cacajao, six in Callicebinae (i.e. Plecturocebus, Cheracebus, and Callicebus), four in Chiropotes, and three in Pithecia, some of them reported for the first time. Both cryptic and conspicuous species in this group presented high allelic diversity.

Sarah A. Boyle - One of the best experts on this subject based on the ideXlab platform.

  • Run, hide, or fight: anti-predation strategies in endangered red-nosed cuxiú (Chiropotes albinasus, Pitheciidae) in southeastern Amazonia.
    Primates, 2017
    Co-Authors: Adrian Barnett, Sarah A. Boyle, Eleonore Z F Setz, Wilson R. Spironello, João M. Silla, Tadeu Oliveira, Bruna M. Bezerra, Rafaela F. Soares Silva, Samara Albuquerque Teixeira, Lucy M. Todd
    Abstract:

    Although primate predation is rarely observed, a series of primate anti-predation strategies have been described. Energetic costs of such strategies can vary from high-cost mobbing, via less costly alarm calling, to low-cost furtive concealment. Here we report the anti-predation strategies of red-nosed cuxiu, Chiropotes albinasus, based on direct observations from four study sites in southeastern Brazilian Amazonia. Over a collective period of 1255 fieldwork hours, we observed nine direct interactions between raptors (all potential predators) and red-nosed cuxius. Of these, one (11%) resulted in predation. Raptors involved were: Harpia harpyja (four events), Leucopternis sp. (two events), Spizaetus tyrannus (one event), and unidentified large raptors (two events). Predation attempts occurred in flooded-forest and terra firme rainforest, were directed at both adult and non-adult cuxius, and involved both adult and juvenile raptors. Anti-predation strategies adopted by the cuxius included: (1) group defence and mobbing behaviour (two occasions), (2) dropping into dense sub-canopy (seven occasions), (3) alarm calling (eight occasions), and (4) fleeing to, and hiding in, dense vegetation (eight occasions). During each encounter at least two of these behaviours were recorded. These are the first published records of predation, predation attempts, and anti-predator behaviour involving red-nosed cuxiu.

  • Geographic comparison of plant genera used in frugivory among the pitheciids Cacajao, Callicebus, Chiropotes, and Pithecia.
    American journal of primatology, 2015
    Co-Authors: Sarah A. Boyle, Jean P. Boubli, Bruna M. Bezerra, Cynthia L. Thompson, Anneke Deluycker, Silvia J. Alvarez, Thiago H. G. Alvim, Rolando Aquino, Mark Bowler, Christini B. Caselli
    Abstract:

    Pitheciids are known for their frugivorous diets, but there has been no broad-scale comparison of fruit genera used by these primates that range across five geographic regions in South America. We compiled 31 fruit lists from data collected from 18 species (three Cacajao, six Callicebus, five Chiropotes, and four Pithecia) at 26 study sites in six countries. Together, these lists contained 455 plant genera from 96 families. We predicted that 1) closely related Chiropotes and Cacajao would demonstrate the greatest similarity in fruit lists; 2) pitheciids living in closer geographic proximity would have greater similarities in fruit lists; and 3) fruit genus richness would be lower in lists from forest fragments than continuous forests. Fruit genus richness was greatest for the composite Chiropotes list, even though Pithecia had the greatest overall sampling effort. We also found that the Callicebus composite fruit list had lower similarity scores in comparison with the composite food lists of the other three genera (both within and between geographic areas). Chiropotes and Pithecia showed strongest similarities in fruit lists, followed by sister taxa Chiropotes and Cacajao. Overall, pitheciids in closer proximity had more similarities in their fruit list, and this pattern was evident in the fruit lists for both Callicebus and Chiropotes. There was no difference in the number of fruit genera used by pitheciids in habitat fragments and continuous forest. Our findings demonstrate that pitheciids use a variety of fruit genera, but phylogenetic and geographic patterns in fruit use are not consistent across all pitheciid genera. This study represents the most extensive examination of pitheciid fruit consumption to date, but future research is needed to investigate the extent to which the trends in fruit genus richness noted here are attributable to habitat differences among study sites, differences in feeding ecology, or a combination of both.

  • primary seed dispersal by three neotropical seed predating primates cacajao melanocephalus ouakary Chiropotes Chiropotes and Chiropotes albinasus
    Journal of Tropical Ecology, 2012
    Co-Authors: Adrian Barnett, Sarah A. Boyle, Liliam P Pinto, Bruna M. Bezerra, Waldete C Lourenco, Thais Almeida, Welma Sousa Silva, Beatriz Ronchiteles, Caroline Ross, Ann Maclarnon
    Abstract:

    The Neotropics house two guilds of large arboreal vertebrate seed predators: parrots and the pitheciin primates. Both have diets dominated by immature fruits. The possibility of members of the Pitheciinae (genera Cacajao, Chiropotes and Pithecia) acting as occasional seed dispersers has been mooted, but not experimentally shown. We combined primate behavioural data and seed germination data from three separate field studies in the Brazilian states of Amazonas and Para to analyse patterns of post-consumption seed survivorship for seeds discarded by three pitheciin species (Cacajao melanocephalus ouakary, Chiropotes Chiropotes and Chiropotes albinasus). We then calculated the frequency of dispersal events for four species eaten by C. m. ouakary. All three primate species dropped intact seeds while feeding, and 30.7% of 674 dropped seeds germinated ex situ. Undamaged seeds from unripe and ripe samples germinated (29.3% and 42.7%, respectively), and all three primate species carried some fruits up to 20 m from the parent tree before consuming them. Potential seed-dispersal events varied from 1 (Macrolobium acaciifolium) per fruiting cycle to more than 6500 (Duroia velutina), suggesting that there are differences in dispersal potential. In summary, although they are highly specialized seed predators, these primates may also act as important dispersers for some plant species, and effective dispersal is not restricted to ripe fruits, as immature fruits removed from a tree may continue to mature and the seeds later germinate, a much-neglected aspect of dispersal ecology. The possibility that similar events occur in parrots should be experimentally investigated.

  • Terrestrial Activity in Pitheciins (Cacajao, Chiropotes, and Pithecia)
    American Journal of Primatology, 2012
    Co-Authors: Adrian Barnett, Sarah A. Boyle, Liza M. Veiga, Thiago H. G. Alvim, Mark Bowler, Marilyn M. Norconk, Suzanne Palminteri, Ricardo Rodrigues Dos Santos, Janice Chism, Anthony Di Fiore
    Abstract:

    Neotropical monkeys of the genera Cacajao, Chiropotes, and Pithecia (Pitheciidae) are considered to be highly arboreal, spending most of their time feeding and traveling in the upper canopy. Until now, the use of terrestrial substrates has not been analyzed in detail in this group. Here, we review the frequency of terrestrial use among pitheciin taxa to determine the ecological and social conditions that might lead to such behavior. We collated published and unpublished data from 14 taxa in the three genera. Data were gleaned from 53 published studies (including five on multiple pitheciin genera) and personal communications of unpublished data distributed across 31 localities. Terrestrial activity was reported in 61% of Pithecia field studies (11 of 18), in 34% of Chiropotes studies (10 of 29), and 36% of Cacajao studies (4 of 11). Within Pithecia, terrestrial behavior was more frequently reported in smaller species (e.g. P. pithecia) that are vertical clingers and leapers and make extensive use of the understory than in in the larger bodied canopy dwellers of the western Amazon (e.g. P. irrorata). Terrestrial behavior in Pithecia also occurred more frequently and lasted longer than in Cacajao or Chiropotes. An apparent association was found between flooded habitats and terrestrial activity and there is evidence of the development of a “local pattern” of terrestrial use in some populations. Seasonal fruit availability also may stimulate terrestrial behavior. Individuals also descended to the ground when visiting mineral licks, escaping predators, and responding to accidents such as a dropped infant. Overall, the results of this review emphasize that terrestrial use is rare among the pitheciins in general and is usually associated with the exploitation of specific resources or habitat types. Am. J. Primatol. 74:1106-1127, 2012. © 2012 Wiley Periodicals, Inc.

  • behavioral modifications in northern bearded saki monkeys Chiropotes satanas Chiropotes in forest fragments of central amazonia
    Primates, 2010
    Co-Authors: Sarah A. Boyle, Andrew T. Smith
    Abstract:

    We investigated behavioral differences among seven groups of northern bearded saki monkeys (Chiropotes satanas Chiropotes) living in five forest fragments and two areas of continuous forest at the Biological Dynamics of Forest Fragments Project study area, located approximately 80 km north of Manaus, Brazil. We collected data in six research cycles from July–August 2003 to January 2005–April 2006. When bearded saki monkeys were present in a study area, we followed the group from dawn until dusk for three consecutive days. Every 5 min, we conducted behavioral scans of all visible individuals. There was a positive relationship between forest size and group size, but animals in the small forest fragments lived at greater densities. Bearded saki monkeys in the smaller fragments spent more time resting, less time traveling, and less time vocalizing, but there was no relationship between forest size and the amount of time spent feeding. Our results indicate that the main behavioral differences among the groups are related to the amount of forest resources (e.g., fruit trees, space) available to the monkeys in the smaller fragments, as well as the resulting smaller group sizes. We stress the need to preserve large tracts of forest and provide connectivity between forest patches.