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Navegando por Orientadores "FERRARI, Stephen Francis"

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    Aspectos da ecologia do Cuxiú de Uta Hick, Chiropotes Utahickae (Hershkovitz, 1985), com ênfase na exploração alimentar de espécies arbóreas da ilha de germoplasma, Tucuruí-PA
    (Universidade Federal do Pará, 2005-03-14) VIEIRA, Tatiana Martins; FERRARI, Stephen Francis; http://lattes.cnpq.br/3447608036151352
    In 1985, construction of the Tucurui hydroelectric power station flooded 2400 km² of forest, creating hundreds of different sizes, fragmenting the populations of many organisms, including bearded sakis (Chiropoies spp.). The present study took place on the 129-ha Germoplasma island, which is home to a group of Chiropotes utahickae, which currently contains 23 members, studied previously by Santos (2002). The present study aimed primarily to describe certain aspect of the ecology of Uta Hick's bearded saki and to characterize the dietary exploitation of tree species. Data collection was based on monthly samples of eight days, with basic behavioural data being collected in one-minute scan samples at five-minute intervals, supplemented alternately by focal-tree and focal-fruit sampling. The principal behavioural categories were feed, travel, forage, rest and social interaction (containing several subcategories). A total of 11,277 scan sample records were collected, together with 259 focal tree samples, and 711 focal fruit samples, between March and August 2004. Overall, 50.6% of activity time was devoted to locomotion, 31.9% to feeding, 10.6% to rest, 5.4% to foraging activities, and 1.2% to social interactions. The diet consisted primarily of immature seeds (31.7%), immature mesocarp (21.2%), ripe fruit (18.3%), and flowers (14.4%). Comparisons with the results of Santos (2002) indicate a number of seasonal or longitudinal differences. The sakis exploited fruit of 0.4 to 15.3 cm in length, with seeds of between 0.1 cm and 2.3 cm. The sakis were considered to be seed predators for 74.2% of the 31 species analysed, although no significant relationship was found between predation and seed size. Also, no systematic relationship was found between the distance seeds were transported and their size, suggesting the influence of other factors, such as crown dimensions and feeding party size. Twenty years after isolation, the Germoplasma sakis appear to present typical Chiropotes behaviour patterns. Tolerance of habitat fragmentation appears to be supported by the exploitation of specific resources, such as the immature mesocarp of Inga spp. during a period of resource scarcity, and the consumption of Brazil-nut (Bertholletia excelsa) flowers. Flowers appear to be an especially important resource for the sakis of the Tucuruí reservoir (Santos, 2002; Silva, 2003). The present study constitutes an important contribution to the understanding of the species' s ecology, although it is clear that the Tucurui populations require further monitoring in order to provide more detailed information on diet, social organization, and animal-plant interactions, necessary for the development of sound conservation and management strategies.
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    Caça em assentamento rural no Sul da Floresta Amazônica
    (Universidade Federal do Pará, 2004-05-07) TRINCA, Cristiano Trapé; FERRARI, Stephen Francis; http://lattes.cnpq.br/3447608036151352
    In this study, 1 investigated the effects on the local populations of wild mammals of the hunting activities of the residents of a rural settlement in the Amazonian forest of the northern part of the Brazilian state of Mato Grosso. The second part of the Japuranã settlement — the study site — was occupied three years ago. Formal interviews were conducted with 17 settlers. Additional information was collected informally, during all forms of contact with settlers during the study period. The majority of settlers are from southern and southeastern Brazil. Typically, they are semi-literate rural workers, with very low monthly income. The principal hunting techniques used are "ambush", "chase with dogs" and "excursion". Game meat was an important part of settlers' diets, and was included in about a third of meals. The activities of 14 hunters were monitored between May and November, 2003, during which they captured 113 mammals belonging to 17 species. Analyses of population structure based on crania were possible for only two species, the white-lipped (Tayassu pecari and the collared (Pecari tajacu) peccaries. The analysis indicated that the situation of the structure of the population of the T.pecari and the P.tajacu is sensible and could seriously be affected if the pressure increase. An estimated 4096.3 kg of game was extracted from an area of approximately 38 km2, representing an average consumption of 0.268 kg of meat per person per day. Line transect population surveys were conducted at three sites, two in the settlement and a third in a nearby "control" area of continuous forest where hunting is not practised. Over a total transect of 108 km, 15 species of mammal and four species of bird were recorded, with relatively high sightings rates in comparison with most other sites in central and eastern Amazonia. However, species richness and abundance were greater at both settlement sites in comparison with the control. The abundance of ungulates (peccaries and deer), the primary game species, was also greater in the settlement (both sites) in comparison with the control. This suggests clearly that hunting pressure has not yet had a significant impact on the mammal populations of the settlement, at least in terms of abundance. The majority (85.8%) of hunting was directed at subsistence, while 8.0% involved the control of predators of domestic stock, and the remaining 6.2% was "predatory", basically for the protection of the dogs during chase hunting. Despite this pressure, the relative abundance of mammals in the settlement suggests that hunting is sustainable over the short term (three years), possibly as a result of the natural abundance of mammals in the region, and the still reduced human population density. However, this situation may not last long, given that deforestation and consequent habitat fragmentation is an ongoing process, and there are no controls on hunting in the area. The results of this study provide an important data base for the development of management plans for the local fauna, involving the local community, government, environmental organisations, and research institutions. These plans will be fundamental to both the conservation of species and the more efficient exploitation of game resources by local settlers.
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    O coatá-de-testa-branca (Ateles marginatus) do baixo Rio Tapajós, Pará: distribuição, abundância e conservação
    (Universidade Federal do Pará, 2001-02-16) RAVETTA, André Luís; FERRARI, Stephen Francis; http://lattes.cnpq.br/3447608036151352
    The white-fronted spider monkey, Ateles marginatus, is an endangered species according to IUCN. Endemic to Brazilian Amazonia, its status is due to a combination of a relatively restricted geogaphic distribution and the growing human presence within this area. The present study focussed on the BR-163 (Santarém-Cuiabá) highway, on the right bank of the lower Rio Tapajós, a region of prolonged and intense human occupation. The principal aim of the present study was an evaluation of the distribution and abundance of A. marginatus within this area, and analysis of the factors determining these variables. Residents were interviewed informally at 16 sites in order to confirm the presence or absence of the species. Line transect population surveys were conducted at eight sites, representing differing degrees of habitat fragmentation, with a total transect length of 697.6 km. Groups of A. marginatus were monitored at two sites for the collection of data on their behaviour and ecology. The results indicate that the species is absent from some areas, including natural lacunae in its distribution as well as a zone of local extinction, that appears to extend as least as far as 60 km south of the city of Santarém. A total of 23 species of nonflying mammals were recorded in the population surveys, but the presence of A. marginatus was confirmed at only three sites. The study indicates that isolated fragments of forest of less than one hundred hectares are unable to support populations of A. marginatus. In the case of larger fragments, the presence and abundance of the species appears to be influenced more directly by human factors (hunting and logging). The species seems to be relatively rare even in continuous forest, which is similar to other populations of Ateles in Brazilian Amazonia. Two groups, one with eight members and the other with at least twenty, were identified during monitoring. As in other members of the genus, the formation of subgroups (fission-fusion), a relatively high proportion of females in the population and a frugivorous diet are also observed in A. marginatus. The study reveals the critical situation of the species in the region, in the face of human occupation, and the urgent need both to deter the process of habitat fragmentation and establish new protected areas.
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    Comportamento alimentar do Cuxiú-Preto (Chiroptes Satanas) na área de influência do Reservatório da Usina Hidrelétrica de Tucuruí-Pará
    (Universidade Federal do Pará, 2003-03-21) SILVA, Suleima do Socorro Bastos da; FERRARI, Stephen Francis; http://lattes.cnpq.br/3447608036151352
    Constructed in 1985, the Tucuruí hydroelectric power station created a 2430 lun2 lake (3°43'-5°15’S, 49°12'-50°00'W), and restricted populations of the southem bearded saki (Chiropotes satanas), an endangered primate, to a series of islands and other habitat fragments. This study took place at two sites on the lake's right bank, one in continuous forest (T4) and the other on a small island of 16.3 hectares (Su), with groups of 34 and seven sakis, respectively. The principal objective was an evaluation of the influence of habitat fragmentation on the sakis' foraging behaviour. Basic data were collected in one-minute scan samples with a five-minute interval, whereas foraging behaviour was recorded in greater detail in focal-tree samples, and behavioural sampling. Basic behavioural categories were locomotion, rest, forage, feed, and social interaction, with a number of subcategories. Between July and December 2002, 3503 scan records were obtained for group T4, and 835 for group Su. 'The activity budget of T4 was 55.8% locomotion, 21.7% feed, 16.1% rest, 3.6% forage, and 2.8% social interactions. Feeding was recorded at a similar proportion (22.4%) for Su, although this group spent significantly less time in locomotion (45.9%), and more at rest (27.0%). A major difference was also found in the number of plant species exploited for the dietary resources, 40 for T4 (Arecaceae being the most important family) but only 22 for Su (Lecythidaceae), although no significant difference was found in the diversity of their diets. The composition of their diets was significantly different, however, the major item for T4 was immature seeds (the mesocarp of palm fruits was also important), whereas the consumption of flowers — practically all from the species Alexa grandiflora (Leguminosae) — was very frequent in Su. The differences between groups seem to be at least partly related to that in their home ranges, which was 68.9 hectares for T4 and only 16.3 ha (the whole island) for Su. Aspects of the behaviour of group Su members, such as increased rest and feeding on flowers, may reflect the effects of habitat fragmentation on their ecology, with negative implications for the group's long term survival. It is hoped that these results will make a significant contribution to the development of effective conservation strategies at this endangered primata as well in the fragmented landscape of eastern Amazonia.
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    Comportamento alimentar e dispersão de sementes por guaribas (Alouatta belzebul) na Estação Científica Ferreira Penna (Caxiuanã / Melgaço / Pará)
    (Universidade Federal do Pará, 1999-04-13) SOUZA, Luciane Lopes de; FERRARI, Stephen Francis; http://lattes.cnpq.br/3447608036151352
    The behaviour of two free-ranging groups of red-handed howler monkeys (Alouatta belzebul) was monitored at the Ferreira Penna Research Station (Pará) over' a thirteen-month period in 1997/98, in order to record their ecological characteristics, especially their diet and seed dispersal. Quantitative behavioural data were obtained using instantaneous scan sampling. Invariably, the howler monkeys were relatively inactive, dedicating more than half their activity time to resting, and much smaller proportions to locomotion, feeding and social behaviour. Use of the home range was strongly influenced by the distribution of food patches, in particular fruiting trees. The diet was basically folivorous-frugivorous, although fruit was the item consumed most frequently (54.1 % of feeding records for the principal group, denominated "L") in the "winter" months (November-April), whereas leaves were consumed far more frequently (84.5 %, group L) in the "summer" (May-August). Seeds took 22:49±6:12 h, on average, to pass through the digestive tract, and ingested seeds were dispersed a mean distance of 172,0±113,8 m, although this distance was significantly greater in the winter. Germination rates recorded in tests in both field and laboratory were inconclusive on the effects of ingestion on viability. The germination rate of ingested seeds was significantly greater than the control (uningested) in only a few cases, such as that of Ficus guianensis, the principal source of fruit. Even so, ingestion did not have a marked negative effect on viability in any case. Overall, the present study reforces the view of A. belzebul as a typical howler monkey, ecologically, albeit relatively frugivorous, and playing a important role as a seed disperser in the Amazon Forest.
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    Ecologia comportamental de Alouatta belzebul (Linnaeus, 1766) na Amazônia Oriental sob alteração antrópica de hábitat
    (Universidade Federal do Pará, 2005-03-14) CAMARGO, Carolina Cigerza de; FERRARI, Stephen Francis; http://lattes.cnpq.br/3447608036151352
    The behavioural ecology of two groups of red-handed howler monkeys (Alouatta belzbul) was monitored ou Gennoplasma island (Tucuruí, in the Brazilian state of Pará), between April and September 2004. The two study groups were of similar size and composition, but inhabited different forest types: native forest (group P) and a plantation of native tree species (group Q). Quantitative behavioural data were collected in three-minute scan samples conducted at ten-minute intervals. "AH events" sampling was used to record rare activities such as social and interspecific interactions. Resting was the predominant activity in both groups (P: 67.3%; Q: 61.9%), followed by feeding (P: 15.7%; Q: 21.4%), and locomotion (P: 15.8%; Q: 15.5%). The proportions of the first two categories were significantly different. The diet of both groups was folivorous-frugivorous, supplemented mainly by flowers. No significant seasonal variation was recorded in the diet of either group. The groups occupied home ranges of similar size (P: 5.25 ha; Q: 5.50 ha), although group P travelled 612 m ou average per day, as against 541 m for group Q. Both groups used preferentially their "original" habitat (group P: native forest; group Q: plantation), and the uppermost forest strata. Interspecific interactions were pacific, and social interactions were rare. The results of the present study present greater similarities with those of A. belzebul studies carried out in fragments of Atlantic Forest than at other Amazonian sites (continuous forest). This suggests that habitat disturbance may be a more important determinant of behaviour patterns than the characteristics of the biome. Overall, the results of the present study conicide with the typical Alouatta patterns of behaviour described in the literature.
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    Ecologia de cuxiús (Chiropotes Satanas) na Amazônia oriental: perspectivas para a conservação de populações fragmentadas
    (Universidade Federal do Pará, 2002-10-04) SANTOS, Ricardo Rodrigues dos; FERRARI, Stephen Francis; http://lattes.cnpq.br/3447608036151352
    Found throughout much of Brazilian Amazonia, the bearded sakis (Chiropotes albinasus and Chiropotes satanas) are primates specialised for seed predation. In order to delineate activity patterns and the exploitation of dietary resources, two social groups (10 and B4) of C. satanas were monitored between July and November, 2001, at the reservoir of the Tucurui hydroelectric power station in the state of Pará. Group 1G (C.s. utahicki), with 24 members, occupies an island of 100 ha, whereas group B4 (C. s. satanas), with 27 members, inhabits an area of continuous forest, both protected by Eletronorte S.A. Quantitative behavioural data were collected in scan samples, with a 5 min interval, collected continuously during five days per month. Complementary observations were recorded in ad libitum fashion throughout the study period, which started in April. A total of 5490 reords were collected for group 1G (only the feeding behaviour of group B4 was analysed here), distributed between feeding (58,8%), locomotion (30,8%), rest (9,5%) and other activities (0,9%). These proportions varied considerably between months. One hundred and ten plant species were exploited by the sakis. As expected, seeds were the main dietary item in both cases (group 1G: 75,6%, n = 2721 records; group B4: 49,6%, n = 1865). Remaining dietary items included flowers, fruit, leaf shoots and the mesocarp of palm fruits, although insectivory was not observed. Similar variation in the consumption of different items was observed in the two groups between September and November. Taxonomic diversity of the diet of group 1G was greater than that of B4, as was its home range (100 vs. 57 ha). No systematic variation was found in foraging party size. The results of the study indicate that the remnant populations of bearded sakis in the region's fragmented landscape have good long-term potential for conservation.
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    Ecologia de dois grupos de sagüis-brancos, mico argentatus (Linnaeus 1771) em um fragmento florestal natural, Santarém-Pará
    (Universidade Federal do Pará, 2006) CORRÊA, Honorly Kátia Mestre; FERRARI, Stephen Francis; http://lattes.cnpq.br/3447608036151352
    This monograph presents the results of a long-term study of the behaviour and ecology of two free-ranging groups of Mico argentatus in a natural fragment of forest isolated within a matrix of savanna vegetation in the region of Alter do Chão, in central Amazonia. The groups, denominated Cm1 and Cm2, were habituated and then monitored during 12 months in 2000 and four months in 2001 (Cm1), and seven and three months, respectively, in the two years (Cm2). Analyses of temporal variation were based on three distinct seasons (early wet, late wet, and dry seasons) of 2000, and the longitudinal comparison of July and September in 2000 and 2001. Relationships between ecological variables (abundance of principal resources: fruit and insects) and the ecological and behavioural characteristics of the group were evaluated. The two groups presented distinct composition and sizes, varying from 4-8 and 8-11 members in Cm1 and Cm2, respectively. Quantitative data were collected using scan sampling, with a scan of one minute duration conducted at five-minute intervals throughout the daily activity period of the group. The results show that both groups dedicate more than half their time to foraging and feeding. Diet was composed of fruit, nectar, gum, and animal prey (invertebrates – primarily orthopterans, formicids, and coleopterans – as well as lizards and amphibians). In 2000, groups Cm1 and Cm2 occupied home ranges of 11.5 ha and 14.6 ha, respectively. The seasonal analysis showed a similarity between groups in the systematic allocation of increasing time to foraging and feeding as non-gum resources became scarcer. In addition to a 30% decline in precipitation between years, the longitudinal analysis revealed considerable changes in the composition and spatial distribution of the study groups. These changes appear to have had the main influence on behaviour patterns, resulting in contrasting trends in the two groups. Overall, despite important similarities, the marked differences in many aspects of the ecology of two groups occupying the same fragment constituted one of the principal results of the study, in addition to the considerably variation among seasons and between years. The behavioural strategies records in the study appear to reflect not only the typical variability and flexibility of the callitrichids, but also the ecological conditions imposed by the fluctuations in the availability of resources within a fragment of reduced size.
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    Ecologia e comportamento do Cuxiú-Preto (Chiropotes Satanas) na paisagem fragmentada da Amazônia Oriental
    (Universidade Federal do Pará, 2006-06-13) VEIGA, Liza Maria; GALVÃO, Olavo de Faria; http://lattes.cnpq.br/7483948147827075; FERRARI, Stephen Francis; http://lattes.cnpq.br/3447608036151352
    Bearded sakis are frugivores specialised for seed predation. The black bearded saki (Chiropotes satanas) is endemic to a densely populated and deforested area in eastern Amazonia in Brazil and is threatened with extinction. The principal objective of this study was to research the behaviour and ecology of two groups of black bearded sakis living under different degrees of habitat fragmentation, to understand how ecological parameters in these different settings influence behavioural strategies. In addition, the study aimed to identify factors that may limit the long-term viability of the black bearded saki and identify information that may contribute to conservation and management plans. The study took place on the right bank of the Tocantins River in the Tucuruí Reservoir, Pará State, Brazil (415'S, 4931'W). Two groups of bearded sakis were studied: one (denominated T4) in a large mainland fragment (1,300 ha - 39 members), and one on a small (19.4 ha - eight members) forested island. Twelve months behavioural sampling (1,153 observation hours) was undertaken using both scan and behaviour-sampling methodologies for 4 to 5 consecutive days per month per group. In addition to collecting activity budget data, all food resources were documented, daily routes plotted and intraspecies and interspecies social interactions recorded. Botanical transects (10 x 100 ha) covering one hectare at the T4 site and 0.5 hectare on the island were established, and a subsample of trees (≥ DAP 10cm) and lianas (≥ DAP 5 cm) marked and measured for a floristic inventory and phenological data collection which took place at 30-day intervals over 14 months. The two groups differed in all aspects of their behaviour and ecology. Time spent in different activities varied significantly between the groups. Moving (35.4%) comprised the largest proportion of annual budget in the T4 group, while the Island group devoted more time to feeding (30.0%). Social interactions accounted for a relatively large proportion of activity budget for both groups (T4 8.5%; Island 15.2%). Over the study, the two groups consumed a large number of different plant species (T4 173; Island 132; both groups 240) and their diets varied significantly in terms of items consumed and taxonomic composition. Both groups spent most of their time consuming seeds (T4 54.0%; Island 59.9%), however other items, including fruit pulp (T4 25.0%; Island 13.7%), flowers (T4 12.3%; Island 17.4%) and to a lesser extent pith and arthropods were also included in their diets. Members of the T4 group used an area of 98.6 ha and the island group, 17.2 ha. Use of space and daily path length (T4 4025 m 994 m; Island 2807 m 289 m) varied between groups and was linked in T4 group to the variation in group size throughout the year as a result of their complex fission-fusion sociality, the island group on the other hand was more cohesive. Variations in ecology and behaviour of the two groups were linked to differences in their respective habitats. The size of the sites was important but so too was the variation in the availability of food. Results from the floristic inventory revealed a greater diversity of different species on the T4 site, however important food species were either missing or available in varying amounts at both site. In addition to the intrinsic value of the knowledge of ecological characteristics of the bearded saki the detailed knowledge accumulated this study will help in the formulation of conservation action and management plans and in the identification of the factors which limit the long term viability of remaining populations in the fragmented landscapes of eastern Amazonia.
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    Efeitos de fragmentação de hábitat sobre a prevalência de parasitoses intestinais em alouatta belzebul (Primates, Platyrrhini) na Amazônia Oriental
    (Universidade Federal do Pará, 2002-05-17) MARTINS, Simone de Souza; FERRARI, Stephen Francis; http://lattes.cnpq.br/3447608036151352
    Parasitological studies of natural populations of neotropical primates are relatively rare, and few data were available previously for the red-handed howler monkey, Alouatta belzebul. In the present study, populations of A. belzebul were sampled at five sites in the area of the reservoir of the Tucuruí hydro-electric dam in southeastem Brazilian Amazonia, corresponding to the right bank of the Rio Tocantins. Sites included continuous forest and fragments of habitat on islands varying in area from 180 to 484 hectares. A primary aim of the study was the evaluation of the effects of habitat perturbation on patterns of infestation for endoparasites. Population density was estimated at each site using standard line transect surveys of 100-108 km per site. Fecal samples were collected from six to fourteen groups at each site, with a total of 40- 46 individual samples per site (n = 212). Samples were fixed in MIF (Mercury Chromed, Iodine and Formaldehyde), and observed under a 400x optic microscope. Population density varied between 66,4 and 191,5 individuals per square kilometer. Overall, 76,4% of the samples were positive for at least one species of endoparasite, and a total of thirteen species were identified, including eight species of heiminthes and five protozoans. Individual samples contained as many as five different species of endoparasites. At a given site, the number of species identified varied between seven and twelve, and infection rates between 67,5% and 86%. No systematic pattern of parasite diversity or infection rates was found in relation to variables such as population size or density, or habitat fragmentation. Diversity and infection rates varied as much between the two continuous forest sites as among the forest fragments, and were lowest overall at the site with the lowest population density. The only exception was Trypanoxyuris minutus, a common oxyurid transmitted through direct contact, for which a strong correlation was found between infection rates and population density. Overall, little evidence was found to support the hypothesis that habitat fragmentation has a systematic effect on infestation patterns in A. belzebul, although more detailed studies will be recommend before more definitive conclusions can be drawn.
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    Propondo um problema de forrageio como meio de enriquecer o cativeiro: um estudo comparativo de duas espécies de primatas brasileiros (Callithrix penicillata e Saguinus imperator)
    (Universidade Federal do Pará, 2003-10-17) CASTRO, Paulo Henrique Gomes de; FERRARI, Stephen Francis; http://lattes.cnpq.br/3447608036151352
    This study analysed the influence of a simple insect foraging puzzle on the behaviour of two callitrichine species (Callitrichinae, Primates) maintained in captivity at the National Primate Centre (CENP), in Ananindeua, in the Brazilian state of Para. In addition to comparing the two species, the study aimed to evaluate the viability of the puzzle as a strategy of environmental enrichment for these primates in captivity. Three adult pairs of each species – the pencil-tufted marmoset (Callithrix penicillata) and the emperor tamarin (Saguinus imperator) – were included in the study, which also focussed differences between genders. Observations were conducted through the video-taping of three-hour sessions, divided into control (puzzle absent) and experimental (puzzle present) periods, with a total of 36 hours of observation for each pair. Control sessions were used to calculate baseline activity budgets for comparisons with behaviour patterns during experimental sessions. Tapes were transcripted, and all behaviour events were timed, providing measures of both the frequency and duration of events. The puzzle did not have a major effect on general activity budgets, but its effect was clearly different in each species, with manipulation of the puzzle accounting for 3.96% of the time of the marmosets, but only 1.99% of that of the tamarins. During experimental sessions, the marmosets spent 17% less time at rest in comparison with their baseline budget, whereas rest was reduced by less than 7% in the tamarins, with general activity increasing 10%. These changes varied considerably when comparing genders, however – male tamarins presented a 58% increase in general activity and a 23% reduction in rest, whereas these values were 4% and 10%, respectively, in male marmosets. Female tamarins presented an opposite pattern, with rest increasing 18% and general activity falling 14%, while female marmosets had a reduction in both categories by a little less than ten percent. All the animals learned to manipulate the puzzle and capture insects, although the marmosets were far more persistent, capturing 54% more insects, on average, than the tamarins. Females were more successful in both species, but only marginally so in the marmosets. In the tamarins, by contrast, females were 16% more successful than males. Overall, the puzzle proved to be efficient as a means of enriching the captive environment of both species, by stimulating manipulative behaviour and reducing inactivity.
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