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Funding: Floristic identification in plots in the RAINFOR forest monitoring network have been supported by the Natural Environment Research Council (grants NE/B503384/1, NE/ D01025X/1, NE/I02982X/1, NE/F005806/1, NE/D005590/1 and NE/I028122/1) and the Gordon and Betty Moore Foundation. In a time of rapid global change, the question of what determines patterns in species abundance distribution remains a priority for understanding the complex dynamics of ecosystems. The constrained maximization of information entropy provides a framework for the understanding of such complex systems dynamics by a quantitative analysis of important constraints via predictions using least biased probability distributions. We apply it to over two thousand hectares of Amazonian tree inventories across seven forest types and thirteen functional traits, representing major global axes of plant strategies. Results show that constraints formed by regional relative abundances of genera explain eight times more of local relative abundances than constraints based on directional selection for specific functional traits, although the latter does show clear signals of environmental dependency. These results provide a quantitative insight by inference from large-scale data using cross-disciplinary methods, furthering our understanding of ecological dynamics. Publisher PDF

Critical thermal maximum (CTmax ) is often used as an index of upper thermal tolerance in fishes; however, recent studies have shown that some fishes exhibit agitation or avoidance behavior well before the CTmax is reached. In this study, we quantified behavioral changes during CTmax trials in two Amazonian cichlids, Apistogramma agassizii and Mesonauta insignis. The thermal agitation temperature (Tag ) was recorded as the temperature at which fish left cover and began swimming in an agitated manner, and four behaviors (duration of sheltering, digging, activity, and aquatic surface respiration [ASR]) were compared before and after Tag . Both A. agassizii and M. insignis exhibited high critical thermal maxima, 40.8°C and 41.3°C, respectively. Agitation temperature was higher in M. insignis (37.3°C) than in A. agassizii (35.4°C), indicating that A. agassizii has a lower temperature threshold at which avoidance behavior is initiated. Activity level increased and shelter use decreased with increased temperatures, and patterns were similar between the two species. Digging behavior increased after Tag in both species, but was higher in A. agassazii and may reflect its substrate-oriented ecology. ASR (ventilating water at the surface film) was extremely rare before Tag , but increased in both cichlid species after Tag and was greater in M. insignis than in A. agassizii. This suggests that fish were experiencing physiological hypoxia at water temperatures approaching CTmax . These results demonstrate that acute thermal challenge can induce a suite of behavioral changes in fishes that may provide additional, ecologically relevant information on thermal tolerance.

Saimiri are neotropical primates with seasonal reproduction, males develop a seasonal fattening condition that has been suggested as a pre-copulatory sexual selection strategy. Furthermore, females mate with multiple males in the same season. This could also favor the evolution of a postcopulatory sexual strategy by sperm competition. In this study, we tested the hypothesis that there is a relationship between the fatted condition and advantageous seminal characteristics in Saimiri collinsi and evaluated its implications for sperm competition. Adult males (N = 10), aged 5-15 years, housed in mixed or only-male groups, were analyzed from June, 2015 to July, 2016. Measurements of weight, axilla, and arm skinfold, and testicular volume were taken monthly, and semen was collected by electroejaculation. A fattening index was developed to quantify and identify fatted males, biometrics, and seminal parameters were compared between the non-fatted and fatted conditions. The fatted males present a larger testicular volume. This is related to the increase in spermatogenic activity necessary to sustain a high ejaculation frequency during the mating season. An increase in seminal volume and in frequency of semen coagulation were detected in fatted males, advantages related to sperm protection in the female reproductive tract. Age and social context were not significant sources of variation for both morphological and seminal traits. A decrease in response from the fatted males in obtaining semen and an increase in the frequency of azoospermic ejaculates were observed. These unexpected results may be due to intense reproductive activities in a short period. The fattening phenomenon has many implications in the sexual selection of squirrel monkeys, and they are still not entirely unveiled. Our results corroborate the idea that, in S. collinsi, the fatted male condition is related to sexual selection, and we found evidence suggesting it may be also expressed by a post-copulatory component, sperm competition.

The present study reviews the records of occurrences of fish species found in the Mamirauá Sustainable Development Reserve (MSDR). The reserve is located in a large section of the middle Solimões River basin, in its interflow with Japurá River. For the elaboration of the list of fish species occurring in Mamirauá Reserve, we used a database of different studies on fish communities carried out in the area over the last three decades, in addition to the material deposited in the ichthyological collections of three scientific institutions, the National Institute for Amazon Research - INPA, the Mamirauá Sustainable Development Institute - IDSM and the Science and Technology Museum of the Catholic University of Rio Grande do Sul - PUCRS. The ichthyofauna of the MSDR is composed of 541 species, encompassing 45 families and 15 orders. These correspond to 20% of all valid species known for the entire Amazonia so far. As observed in other studies in the Neotropical Region, the more represented orders were Siluriformes (209 species) and Characiformes (185 species), followed by the Gymnotiformes (78 species). The results presented here demonstrate a considerable increase (86%) in the knowledge about the fish diversity found in Mamirauá Reserve, in relation to its first list of fish species, published in the 90's. This increase reflects not only the growth in number of studies on fish diversity in the area, with new surveys, but also the continuous taxonomic work on the collections, and descriptions of twenty-eight new species, with one hundred and ten type series. Further surveys are expected to take place in the Northwestern, more isolated areas of the Reserve, and will allow the identification of new occurrences, and may even unveil new fish species yet to be described to Science.. Resumo: Este estudo apresenta uma revisão dos registros de ocorrências das espécies de peixes encontradas na Reserva de Desenvolvimento Sustentável Mamirauá (RDSM), ampla área localizada na bacia do Médio Solimões, em seu interflúvio com o Rio Japurá. Para a elaboração da lista de peixes que ocorrem na Reserva Mamirauá foram utilizados os bancos de dados de diferentes estudos sobre comunidades de peixes realizados na área ao longo das últimas décadas, além de informações referentes ao material tombado nas coleções ictiológicas de três instituições científicas, o Instituto Nacional de Pesquisas da Amazônia- INPA,o Instituto de Desenvolvimento Sustentável Mamirauá - IDSM e o Museu de Ciências e Tecnologia da Pontifícia Universidade Católica do Rio Grande do Sul - PUCRS. A ictiofauna da RDSM é composta por 541 espécies, incluindo 45 famílias e 15 ordens. Estes valores correspondem a cerca de 20% de todas espécies válidas conhecidas para toda a Amazônia até o momento. Assim como em outros estudos na região Neotropical as ordens que apresentaram as maiores riquezas foram siluriformes (209 espécies) e Characiformes (185 espécies), seguidas de Gymnotiformes (78 espécies). Os resultados apresentados neste trabalho demonstram um aumento considerável (86%) no conhecimento sobre a diversidade de peixes encontrados na Reserva Mamirauá, em relação à primeira lista de peixes da RDSM, publicada na década de 1990. Este aumento reflete não apenas o crescimento no número de estudos sobre a diversidade de peixes na área, com a ocorrência de novos levantamentos, como também a intensificação dos trabalhos taxonômicos de classificação e descrição de vinte oito novas espécies com cento e dez séries tipos. Novos levantamentos deverão ocorrer nas áreas mais isoladas da Reserva, na sua porção noroeste. Estas atividades permitirão a identificação de novas ocorrências, e podem até revelar espécies novas a serem descritas..

Integration between ecology and biogeography provides insights into how niche specialization affects the geographical distribution of species. Given that rivers are not effective barriers to dispersal in three parapatric species of squirrel monkeys (Saimiri vanzolinii, S. cassiquiarensis and S. macrodon) inhabiting floodplain forests of Central Amazonia, we tested whether forest structure and tree diversity may explain species differences in niche specialization and spatial segregation. We sampled 6617 trees of 326 species in three habitats (high várzea, low várzea and chavascal) used by three Saimiri species, and estimated tree species richness in each of them. For each tree, we measured variables known to influence habitat use in primates, such as crown area and presence of lianas, epiphytes and hemi-epiphytes. We used ANOVA to compare these variables and performed multivariate analyses (NMDS, ANOSIM and SIMPER) to evaluate dissimilarities in forest structure among each habitat inhabited by the three Saimiri species. We identified differences in the tree species richness, crown area and presence of lianas, epiphytes and hemi-epiphytes between the three habitats for all Saimiri species. NMDS demonstrated that areas of high and low várzeas occupied by S. vanzolinii were clearly separated from the other species. We also found that different plant species contributed to dissimilarity among Saimiri ranges. Our findings support the hypothesis that tree community structure may promote niche specialization and spatial segregation among primates. We discuss how these patterns could have been favored by historical changes in forest flood patterns, the evolutionary history of Saimiri spp., and past competition.

The reproductive parameters are among the most important life history aspects of fishes influenced by environmental variation. During recent years, the main life history strategies of Amazonian fish species were defined mostly by a set of reproductive parameters. In the present work, we sought to describe important life history parameters, in particular on reproductive characteristics of Apistogramma agassizii and Apistogramma bitaeniata, found in floodplain lakes of the Brazilian Amazonia. The species presented a positive sexual dimorphism, and males were significantly bigger than females. For both sexes, four developmental phase of gonad maturation were detected, and based on those it was possible to identify mature, reproductive specimens throughout the entire period of the study. From the ovaries of mature females, fecundity and spawning type were determined. Low fecundity, short spawning periods, possibly separated only by few months, and total spawning are all good indications that A. agassizii and A. bitaeniata evolved an opportunistic strategy in their life history.

Seasonal changes in food availability influence the behavior and diet of primates, and an understanding of dietary changes is important for the development of informed conservation plans. Saimiri vanzolinii is a small-bodied, omnivorous squirrel monkey endemic to the floodplain forests in Central Amazonia. It has a restricted distribution of only ca. 870 km2 and is classified as Vulnerable. We examined seasonal variation in this species’ diet. We collected phenological (presence and absence of ripe fruits from 205 tree species) and dietary and behavioral data for unhabituated groups of S. vanzolinii on nine 2-km transects in the floodplain forests of Central Amazonia for 2 years, encompassing the high-water and low-water periods. Fruit availability was higher, and the monkeys traveled less and fed more during the high-water than the low-water period. There were no seasonal differences between the high-water and low-water periods in the time spent feeding on fruits, flowers, or arthropods. S. vanzolinii spent more time consuming fruit than arthropods in the high-water period, but this was not the case in the low-water period. These findings suggest that food selection changed between seasons, and S. vanzolinii focused more on fruit in the low-water period, when fruit was less available, than in the high-water period, when fruit was more available. These results support the predictions of the ecological constraints model.

In many regions primates are an important dietary resource for isolated human populations, and they are among the most hunted species by traditional and indigenous communities in the Neotropics. Little is known about the characteristics or the spatial and temporal patterns of hunting, which limits a more detailed evaluation of its impact. We describe, quantify and analyse the spatial dynamics of primate hunting in the várzea (seasonally flooded forest) and paleovárzea (characterized by a series of low-lying ridges interspersed with flooded depressions, which result from cyclical depositional processes) environments of Central Amazonia, based on the monitoring of riverine communities at the Amanã and Mamirauá Sustainable Development Reserves over an 11-year period. During this time 402 primate hunting events were recorded, involving the harvesting of 541 individuals of nine species: Alouatta juara, Aotus cf. vociferans, Ateles chamek, Cacajao ouakary, Callicebus lucifer, Cebus albifrons, Saguinus inustus, Saimiri cassiquiarensis and Sapajus macrocephalus. Two hundred and forty of these hunts occurred in the paleovárzea and 162 in the várzea. The distances travelled by the hunters from their communities to the kill sites were significantly different between the environments, with longer distances being covered in the paleovárzea. Hunters in the paleovárzea also hunted across significantly larger areas than those in the várzea. The continuous monitoring of hunting areas and the gathering of data on the exploitation of species are necessary to understand the effects of hunting, as well as to support decision making in the management of the local fauna by traditional communities, and the development of effective conservation strategies for the local game species.

SummaryWe describe morphological and morphometrical characteristics of preantral ovarian follicles from three recently recognized Saimiri species: S. macrodon, S. cassiquiarensis and S. vanzolinii; the last one a threatened species. Ovaries from four adult monkeys were evaluated: one pair from a pregnant S. macrodon, two ovarian pairs from S. cassiquiarensis females (one of them pregnant), and one left ovary from a senile S. vanzolinii, applying classical histology. Follicular preantral population was quantified and morphology and morphometry of primordial, primary and secondary follicles were evaluated. Follicular preantral population varied among species, being 347,153 in the ovaries of the S. macrodon, 270,342 and 278,376 in the ovaries of both adult non-pregnant and pregnant S. cassiquiarensis females, and 28,149 in the ovary from a senile S. vanzolinii. Most follicles were at primordial or transition stages, except for the senile S. vanzolinii female, which presented the lowest percentages of primordial and transition follicles when compared with primary and secondary ones. Most preantral follicles (>70%) were morphologically normal in the ovaries from all studied S. macrodon and S. cassiquiarensis females, but the ovary of the senile S. vanzolinii female presented a significant decrease in the percentage of normal follicles (primordial: 61%, transition: 52%, primary: 54%, and secondary: 48%). In general, follicular diameter increased significantly from primordial to transition, and subsequently from primary to secondary follicles.

Globally, community-based initiatives are effective in protecting ecosystems and the species within them. In this paper, we analyze the emergence and large-scale expansion of a community-based environmental protection system (the Voluntary Environmental Agents Program – VEA Program) in the Brazilian Amazon and identify factors that have determined its success since its inception, 25 years ago. Collective actions to protect the environment in the region have been undertaken by local people for at least 40 years, before their legal regulation in 2001 by the federal government of Brazil, and by the Amazonas state in 2007. The system is based on territorial surveillance and monitoring, and on guidelines for the better use of the territory and its natural resources. Between 1995 and 2020, the VEA Program expanded into the two protected areas where it was first implemented reaching approximately 9 thousand km2 of area protected by the system. The number of people participating also grew in this period by around 2050%, as did the participation of women, which grew by 5600%. The system was replicated in 37 protected areas in central Amazonia, and currently covers almost 200 thousand km2 of Amazon rainforest. From our analyses we unveil four main factors that may have allowed the VEA Program to expand and flourish: (a) the communities' previous demand for an effective control system, (b) its legal formalization and regulation, (c) the support from external institutions, and (d) the consolidation of community-based management programs to fund actions. These factors shall be further investigated as to confirm their critical role in the success of the VEA Program. We demonstrate that this community-based environmental protection system has established itself as a legitimate form of social control, and as a mechanism of socio-environmental governance in the areas in which it operates. By allowing more effective protection of territories, it generates consensus amongst users for the adequate management of natural resources, especially in contexts where government's actions are absent or inefficient. We claim that this system can be replicated in various parts of the world.

Federal University of Par? - Campus Castanhal. Faculty of Veterinary Medicine. Laboratory of Wild Animal Biology and Medicine. Castanhal, PA, Par?, Brazil / Institute of Sustainable Development Mamirau?. Tef?, AM, Brazil. Federal University of Par? - Campus Castanhal. Faculty of Veterinary Medicine. Laboratory of Wild Animal Biology and Medicine. Castanhal, PA, Par?, Brazil / Minist?rio da Sa?de. Secretaria de Vigil?ncia em Sa?de. Instituto Evandro Chagas. Centro Nacional de Primatas. Ananindeua, PA, Brasil. Minist?rio da Sa?de. Secretaria de Vigil?ncia em Sa?de. Instituto Evandro Chagas. Centro Nacional de Primatas. Ananindeua, PA, Brasil. State University of Norte Fluminense Darcy Ribeiro. Laboratory of Animal Reproduction and Breeding. Campos dos Goytacazes, RJ, Brazil. Institute of Sustainable Development Mamirau?. Tef?, AM, Brazil. Institute of Sustainable Development Mamirau?. Tef?, AM, Brazil. Federal University of Par? - Campus Castanhal. Faculty of Veterinary Medicine. Laboratory of Wild Animal Biology and Medicine. Castanhal, PA, Par?, Brazil. Federal University of Par? - Campus Castanhal. Faculty of Veterinary Medicine. Laboratory of Wild Animal Biology and Medicine. Castanhal, PA, Par?, Brazil. Sperm morphometry can be applied to identify different animal groups and species and to evaluate sperm quality. Furthermore, knowledge on species-specific differences will help to enhance biological information, as well as to develop efficient reproductive technologies. The aims in the present study were to describe sperm morphometry from the recently characterized species S. collinsi and S. vanzolinii, to verify if the morphometric sperm patterns are similar or different between both species, and to determine if the sperm morphometry is affected by the levels of sperm defects using the S. collinsi as a model. Semen was collected from S. collinsi (n = 10) and S. vanzolinii (n = 2) monkeys, and sperm was submitted to morphological analysis. From the 10 samples from S. collinsi, five presented sperm of poor quality and two subgroups were formed for this species, i.e. high and poor quality sperm. Data on sperm motility and vigour were analysed, as well morphometric parameters on sperm head and tail. It was observed the normal morphometry was correlated with high quality sperm. Poor quality sperm presented smaller and 7% more ellipticity in their head, when compared with high quality sperm. Sperm from S. vanzolinii presented larger head than those from S. collinsi, but tail lengths were similar. Sperm morphometry can be used as a complementary tool to predict sperm motility and vigour for the S. collinsi species, and S. collinsi appear as a suitable model for S. vanzolinii.

Analises para verificar os niveis de conectividade genetica de populacoes sao de extrema relevância para subsidiar politicas publicas visando o gerenciamento pesqueiro a fim de garantir o manejo e a conservacao desses recursos. O sequenciamento de fragmento do DNA mitocondrial foi utilizado visando analisar a estrutura genetica de populacoes de Symphysodon tarzoo e avaliar a ocorrencia de processos de especiacao, discutindo as possiveis barreiras ao fluxo genico para especie. Noventa individuos de S.tarzoo , provenientes do Lago Amana e areas adjacentes, foram utilizados nas analises. A ausencia de subestruturacao populacional, com a ausencia de formacao de clados de uma mesma localidade, na arvore filogenetica e na rede de haplotipos indica que todas as localidades analisadas constituem uma mesma populacao ou estoque genetico. Outros autores sugerem que este resultado pode decorrer de uma divergencia recente no estoque original, da homogeneidade de habitats e da possivel ocorrencia de dispersao eventual entre as populacoes, colaborando para a manutencao de uma constituicao genetica unica para todas as subpopulacoes consideradas. E indicando tambem uma origem multipla da especie, com a possivel ocorrencia de uma area de hibridizacao entre dois ou mais taxons, contribuindo geneticamente para a formacao e evolucao desse grupo. Como provavelmente se trata de uma metapopulacao distribuida em subpopulacoes, nao foi possivel a identificacao de barreiras fisicas para dispersao da especie ao longo da area de estudo. Desta maneira, provavelmente o manejo da especie na area de estudo pode ser realizado considerando que todos os individuos pertencem a um mesmo estoque genetico.

Ovarian agenesis is an unusual anomaly with traumatic or congenital origin. In the present case report, we describe our findings in a senile S. vanzolinii female. As this neotropical primate species is listed as vulnerable, with limited geographic distribution in the Brazilian Amazonia, ovarian agenesis may be an important finding to be reported.

Population monitoring of endangered species is essential to the improvement of their management and conservation plans. The black-headed squirrel monkey (Saimiri vanzolinii) is a vulnerable species on the IUCN Red List and has extreme geographical endemism, exhibiting the smallest known distribution among Neotropical primates (ca. 870 km2 ), over 90% of which occurs in white-water flooded forests within the Mamiraua Sustainable Development Reserve (MSDR), Brazilian Amazonia. To assess the effectiveness of this protected area in conserving the species, we conducted population monitoring of black-headed squirrel monkeys across five consecutive years (2009-2013) on nine trails 2 km each. Each year samples included both low and high river water periods. We used the distance sampling method, recording the distance to each observed social group as well as counting component individuals. We also calculated annual encounter rates based on the number of individuals sighted every 10 km traveled. Densities ranged from 256 individuals/km2 (2011) to 453 individuals/km2 (2013), and no seasonal differences were detected. Population size was estimated to be 147,848 mature individuals. Encounter rates ranged from 100 individuals/10 km (2010) to 179 individuals/10 km (2013); no significant difference among years was found. We found that S. vanzolinii populations remained stable throughout the years, which indicates that the MSDR has been playing an essential role on protecting this species. Due to difficulties of fulfilling assumptions of the distance sampling method, we consider the encounter rate analysis to be more effective for monitoring this and other Saimiri species. Given the critical endemism and worrying conservation status of S. vanzolinii, we suggest that monitoring of the species population should be carried out regularly.

Arapaima is a widely-distributed fish of enormous economic importance in the Amazon region. In the present study, a total of 232 specimens were sampled, 121 from five sites in the Amazon basin and 111 from five sites in the Tocantins-Araguaia basin. The analyses investigated fragments of the Cytochrome b, Control Region, Cytochrome Oxidase I, NADH dehydrogenase subunit 2 and seven loci microsatellites. The analyses revealed the existence of two mitochondrial lineages within the general area, with no haplotypes shared between basins, and genetic variability significantly higher in the Amazon than in the Tocantins-Araguaia basin. Two divergent, but sympatric mitochondrial lineages were found in the Amazon basin, but only a single lineage in the Tocantins-Araguaia basin. The existence of these two mitochondrial lineages indicates that past events, probably occurring during the Pleistocene, resulted in the separation of the populations of this species and molded its evolutionary history, which is reflected directly in its mitochondrial DNA. The analysis of the arapaima population structure identified distinct levels of diversity within the distribution of the species, indicating specific geographic regions that will require special attention for the development of conservation and management strategies. Made available in DSpace on 2020-06-23T11:11:08Z (GMT). No. of bitstreams: 1 CNPASA-2020-aabc.pdf: 1629663 bytes, checksum: af1e9040bd98872eae31dc15232610aa (MD5) Previous issue date: 2020

Made available in DSpace on 2018-12-11T17:20:34Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-05-01 Office of Legacy Management Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) We determined the filtered tree species pool of Amazonian wetland forests, based on confirmed occurrence records, to better understand how tree diversity in wetland environments compares to tree diversity in the entire Amazon region. The tree species pool was determined using data from two main sources: 1) a compilation of published tree species lists plus one unpublished list of our own, derived from tree plot inventories and floristic surveys; 2) queries on botanical collections that include Amazonian flora, curated by herbaria and available through the SpeciesLink digital biodiversity database. We applied taxonomic name resolution and determined sample-based species accumulation curves for both datasets, to estimate sampling effort and predict the expected species richness using Chao’s analytical estimators. We report a total of 3 615 valid tree species occurring in Amazonian wetland forests. After surveying almost 70 years of research efforts to inventory the diversity of Amazonian wetland trees, we found that 74% these records were registered in published species lists (2 688 tree species). Tree species richness estimates predicted from either single dataset underestimated the total pooled species richness recorded as occurring in Amazonian wetlands, with only 41% of the species shared by both datasets. The filtered tree species pool of Amazonian wetland forests comprises 53% of the 6 727 tree species taxonomically confirmed for the Amazonian tree flora to date. This large proportion is likely to be the result of significant species interchange among forest habitats within the Amazon region, as well as in situ speciation processes due to strong ecological filtering. The provided tree species pool raises the number of tree species previously reported as occurring in Amazonian wetlands by a factor of 3.2. Programa de Pós-Graduação em Ecologia e Biodiversidade Instituto de Biociências Universidade Estadual Paulista (UNESP) Ecosystem Dynamics Observatory Departamento de Geografia Instituto de Geociências e Ciências Exatas Universidade Estadual Paulista (UNESP) Programa de Pós-graduação em Ecologia Instituto de Ciências Biológicas Universidade Federal do Pará/Embrapa Amazônia Oriental Instituto de Desenvolvimento Sustentável Mamirauá Departamento de Ecologia Universidade Federal do Rio Grande do Norte—UFRN Divisão de Sensoriamento Remoto Instituto Nacional de Pesquisas Espaciais Programa de Pós-Graduação em Ecologia e Biodiversidade Instituto de Biociências Universidade Estadual Paulista (UNESP) Ecosystem Dynamics Observatory Departamento de Geografia Instituto de Geociências e Ciências Exatas Universidade Estadual Paulista (UNESP) Office of Legacy Management: # 88881.135761/2016-01 FAPESP: #2015/24554-0 CNPq: #308040/2017-1 CNPq: #310144/ 2015-9

Esta pesquisa buscou caracterizar socioeconomicamente as familias de tiradores de caranguejo-uca das comunidades quilombolas Cacau e Terra Amarela, no Municipio de Colares (PA), e investigar a possivel existencia de particularidades entre elas e outras populacoes tradicionais que se dedicam a essa atividade na regiao. Foram aplicados questionarios semiabertos e tecnica da observacao direta no campo, ambas realizadas ao longo de 2013. Esta diagnose definiu que, nas duas comunidades estudadas, as familias possuem de 4,3 a 4,9 individuos por domicilio, respectivamente. Habitam, em sua maioria, moradia propria, construida em alvenaria, vivendo, entretanto, em mas condicoes de vida e sem quase nenhum acesso aos servicos publicos. No geral, abandonaram o estudo cedo, apresentando a maioria apenas o ensino fundamental incompleto. Alem disso, foi registrada uma renda familiar mensal baixa, majoritariamente variando de menos de meio ate um salario minimo. A baixa remuneracao, associada ao baixo nivel de escolaridade, a infraestrutura deficiente e a ausencia do poder publico local no provimento de servicos, sao algumas das principais caracteristicas associadas a baixa qualidade de vida dessas familias estudadas. Tais condicoes mostraram-se bastante semelhantes as de outras comunidades tradicionais nao quilombolas que vivem e trabalham em condicoes semelhantes na regiao costeira do Para.

We describe the most important reproductive aspects of the flag cichlid Mesonauta insignis in the floodplain (varzea) lakes of the Central Brazilian Amazon. Between September 2005 and August 2006, fish were collected monthly from mattresses of aquatic macrophytes. Biometric measurements as well as macroscopic and microscopic analyses of the gonads were performed. Standard body lengths ranged from 2.4 to 9.3 cm, and weight−length relationships were indicative of isometric growth patterns. Reproduction events were detected in all months, but the gonadosomatic index indicated a reproductive season from October to February (during low and rising water periods), reaching a reproductive peak in February. Average fecundity was 1184 ± 40.82 (mean ± SD) mature oocytes. M. insignis exhibits an asynchronous oocytal development, characteristic of multiple spawnings. Morphological and histological analyses indicated 5 gonadal maturation stages for females. Average standard length at first sexual maturation was 5.18 cm for females and 5.5 cm for males. M. insignis shows late sexual maturation. Taken together, these aspects suggest that a life history strategy of ‘equilibrium’ predominates in the species; consequently, M. insignis can be considered vulnerable to high extraction rates, and can only be exploited sustainably if adequate precautionary management procedures are adopted. Some management measures are suggested for the exploitation of this species in the Central Amazon.

The squirrel monkey, Saimiri, is a pan-Amazonian Pleistocene radiation. We use statistical phylogeographic methods to create a mitochondrial DNA-based timetree for 118 squirrel monkey samples across 68 localities spanning all Amazonian centers of endemism, with the aim of better understanding (1) the effects of rivers as barriers to dispersal and distribution; (2) the area of origin for modern Saimiri; (3) whether ancestral Saimiri was a lowland lake-affiliated or an upland forest taxa; and (4) the effects of Pleistocene climate fluctuation on speciation. We also use our topology to help resolve current controversies in Saimiri taxonomy and species relationships. The RondÔnia and Inambari centers in the southern Amazon were recovered as the most likely areas of origin for Saimiri. The Amazon River proved a strong barrier to dispersal, and squirrel monkey expansion and diversification was rapid, with all speciation events estimated to occur between 1.4 and 0.6. Ma, predating the last three glacial maxima and eliminating climate extremes as the main driver of squirrel monkey speciation. Saimiri expansion was concentrated first in central and western Amazonia, which according to the "Young Amazon" hypothesis was just becoming available as floodplain habitat with the draining of the Amazon Lake. Squirrel monkeys also expanded and diversified east, both north and south of the Amazon, coincident with the formation of new rivers. This evolutionary history is most consistent with a Young Amazon Flooded Forest Taxa model, suggesting Saimiri has always maintained a lowland wetlands niche and was able to greatly expand its range with the transition from a lacustrine to a riverine system in Amazonia. Saimiri vanzolinii was recovered as the sister group to one clade of Saimiri ustus, discordant with the traditional Gothic vs. Roman morphological division of squirrel monkeys. We also found paraphyly within each of the currently recognized species: S. sciureus, S. ustus, and S. macrodon. We discuss evidence for taxonomic revision within the genus Saimiri, and the need for future work using nuclear markers. © 2014 Elsevier Inc.

The floodplain forests in the Amazon basin suffer from the continued exploitation of natural resources and, after being disturbed, show slow and sometimes irreversible recovery. Our goal was to create an index that could be used to assess the relative level of human disturbance in floodplain forests and determine the relative importance of different types of disturbance on a given site and between sites. The index proposed here (Flooded Forest Anthropization Index – FFAI) assesses human disturbance on a local scale and is composed by 15 indicators divided into three groups that represent different levels of impact: (1) simplification of ecosystems and reduction of local diversity; (2) ecosystem replacement/destruction; (3) disturbances with the potential to impact the ecosystem in both ways. The FFAI proved to be robust and revealed a wide range of values in the evaluated landscapes. The sites classified a priori as more anthropogenic showed significantly higher FFAI values than the less anthropogenic ones (0.14 ± 0.05 and 0.08 ± 0.02, respectively, F = 18.9, df = 19, p

Aim: \ud Our aim was to examine gracile capuchin (Cebus) and robust capuchin monkey (Sapajus) diversification, with a focus on recent Sapajus expansion within Amazonia. We wanted to reconstruct the biogeographical history of the clade using statistical methods that model lineages’ occupation of different regions over time, to evaluate recently proposed “Out of Amazonia” and “Reinvasion of Amazonia” hypotheses as alternative explanations for the extensive geographic overlap between reciprocally monophyletic gracile (Cebus) and robust (Sapajus) capuchin monkeys. \ud Location:\ud Central and South America.\ud \ud Methods:\ud We reconstructed a time-calibrated molecular phylogeny for capuchins under Bayesian inference from three mitochondrial genes. We then categorized 12 capuchin clades across four Neotropical centres of endemism and reconstructed the biogeographic history of the capuchin radiation using six models implemented in ‘BioGeoBEARS’. We performed a phylogeographic analysis for a robust capuchin clade that spans the Atlantic Forest, Cerrado, Caatinga and Amazonia.\ud \ud Results:\ud We find support for a late Miocene vicariant Cebus-Sapajus divergence and a Pleistocene Sapajus invasion of Amazonia from the Atlantic Forest. Our new analyses confirm Sapajus diversified first in the Atlantic Forest, with subsequent range expansion into widespread sympatry with Cebus in Amazonia, as well as multiple expansions into drier savanna-like habitats. We do not find mitochondrial molecular congruence with morphological species distinctions for Sapajus flavius, S. cay, S. macrocephalus, S. libidinosus and S. apella; instead, these five morphological types together form a single widespread clade (Bayesian posterior probability = 1) with geographic substructure and shared ancestry during the Pleistocene.\ud \ud Main conclusions:\ud Our results support vicariance dividing ancestral capuchin populations in Amazonia versus the Atlantic Forest, and a Pleistocene “Amazonian invasion” by Sapajus to explain the present day sympatry of Cebus and Sapajus.

The variation in water level in the Amazon varzea promotes cyclical isolation or union of various bodies of water. Among these, lakes and channels are the most relevant. Due to their cyclical geographic isolation, and even due to the often distinct origin of their waters, these environments showed limnological features which also vary from those bodies of water located outside the varzea setting. The objective of this study is to demonstrate the differentiation of the types of water bodies present in the Middle Solimoes area, inside and outside of the floodplain areas, by segregating their main physical and chemical parameters. It also aims to evaluate the influence of the flood pulse on these parameters in these types of bodies of water. In order to do this, expeditions were conducted monthly from 2004 to 2011, at twelve sampling stations located in different types of water bodies, including canals and lakes within the Mamiraua Sustainable Development Reserve, the Solimoes River and the mouth of the Tefe River. The parameters monitored were electrical conductivity, temperature, dissolved oxygen, oxygen saturation, pH and transparency. To analyze the data obtained from this monitoring, descriptive statistics and clustering were used. The temperature of the bodies of water in the Mamiraua RDS showed mean values ranging between 27.1 and 30.8 ° C. Dissolved oxygen concentrations resulted in average concentrations of from 0.3 to 0.6 mg.L-1, with a high standard deviation. Transparency was between 0.4 and 1.6 m. Electrical conductivity ranged between 87 and 204 μS.cm-1 in white waters and 10 - 21 μS.cm-1 in black/mixed waters of the mouth of the Tefe River. From the groupings obtained, it was possible to state that the lakes behave like independent bodies of water in the daught season, and during the season of high water they form a large grouping, suggesting a greater homogenization. An analysis of principal components with the parameters confirmed their relevance in the structuring of groups or types of bodies of water identified in the region. The pH distinguished itself as the main differentiating factor between white and black waters, followed by water transparency. Electrical conductivity was the main parameter responsible for the differentiation of water in different periods of the hydrological cycle, followed by water transparency. The variation in water level during the hydrological cycles evaluated over seven years of monitoring influenced the water quality in the lakes and canals of Mamiraua Sustainable Development Reserve and the Solimoes and Tefe Rivers. The parameters transparency, dissolved oxygen, and conductivity varied more markedly between the periods of draught and high water.

This work investigates life strategy elements of the neotropical cichlid Aequidens tetramerus in the lakes of Central Amazon varzea, predominated by white waters. During the 2011 hydrological cycle, fish were captured monthly from banks of aquatic macrophytes present in the lakes studied. The animals found had total maximum lengths of 18.5 cm and 20 cm for females and males, respectively. The average length recorded for their first sexual maturation was 6.49 cm and 8.35 cm for females and males, respectively. Species reproduction occurred throughout the hydrological cycle, but the peak of the reproductive activity was observed during the period of rising water. The average fertility was 1,477 oocytes. The diametric distribution of these oocytes showed synchronous development in more than two groups, suggesting partial spawning. It seems that A. tetramerus reaches sexual maturation early in its life time. Based on the reproductive attributes unveiled in this study and on the fact that the species performs parental care, it is suggested that this is a predominantly K-strategist species.

The white bald uakari (Cacajao calvus calvus) is among the least studied of the Amazonian primates and is found exclusively in remote areas of the central Amazon. The geographic distribution of this subspecies is still uncertain, and information on current threats and its conservation status is sparse. In this paper, we identify new locations of occurrence and propose range expansion of the Cacajao calvus calvus. Between 2008 and 2010, six field expeditions were undertaken in the middle Solimões region to search for the subspecies and to conduct interviews with local residents regarding its presence. The presence of the white bald uakari was confirmed in the lower courses of the Juruá and lower Jutaí rivers, in addition to areas inside the Mamirauá Reserve, where its presence was expected. Results indicate an expansion and new limits on the geographic range of the subspecies, including its detection in areas in which it had not previously been reported and its exclusion from areas where white bald uakaris were assumed to occur. The new information provided by this study and the remaining shortcomings regarding the distribution of the calvus group point to the urgent need for further research on the geographic distribution and habitat use of this group, especially along the lower courses of the Juruá and Jutaí rivers, which remain little explored.

Eleven taxa of primates are found in the floodplains of the western portion of the central Brazilian Amazon, protected in part by the Mamiraua Sustainable Development Reserve. The taxonomy of the squirrel monkeys, the number of taxa, and their geographic distributions are still poorly understood. Here we investigate differentiation among the taxa of this genus in Mamiraua, examining their morphology and geographic distribution. We registered 333 points of occurrence of squirrel monkeys and examined 117 specimens deposited in scientific collections. The results of the morphological analyses were generally in good agreement with field observations. Together they indicate the existence of three taxa: Saimiri vanzolinii, Saimiri sciureus macrodon, and S. s. cassiquiarensis. The restricted range of Saimiri vanzolinii in the southeastern portion of the reserve covers an area of 870 km2, and it is among the smallest of the distribution areas for any Neotropical primate species. Saimiri sciureus cassiquiarensis has a disjunct distribution, crossing the Japura River to the right bank into the reserve in two places, and S. s. macrodon is the squirrel monkey ranging widely in the northwest of Mamiraua. There are three areas of parapatry: one between Saimiri vanzolinii and Saimiri sciureus macrodon and two between S. vanzolinii and S. s. cassiquiarensis. We recommend that anthropogenic changes in the region be monitored, and conservation measures be taken to protect these primates, especially considering the endemism and very restricted range of Saimiri vanzolinii and its consequent vulnerability to extinction.

The diet of Astronotus ocellatus (Osteichthyes, Cichlidae) and the morphometry of its digestive tract were investigated at Mamiraua Sustainable Development Reserve (MSDR), Amazonas, Brazil, between February 2005 and January 2006. A total of 223 specimens were captured and from each of them the total and standard length, length of intestine, and length of abdominal cavity were determined. The intestinal coefficient and the celomatic coefficient were calculated. Contents from stomachs and intestines were analyzed in 182 specimens. Data gathered show A. ocellatus as a carnivorous species, and insects and fish proved to be the most important food items in its diet. It was detected a significant difference in the composition of diets between intestinal and stomach contents, suggesting the importance of separate analysis to better describe the use of food resources available for the fish species in this particular environment. During the year of study the diversity index of the diet was higher in the low water period.

In middle Solimoes River the longest-running initiative of turtle community-based protection ( Podocnemis sextuberculata, P. unifilis and P. expansa ) occurs in the Mamiraua Reserve. This study aimed to compile and analyze existing information on the community-based conservation of turtles in this region and discuss the effectiveness of this strategy for generation of scientific data and conservation purposes. We analyzed available information and compared it with data obtained through participant observation. In the last years turtle conservation expanded from beaches into lakes. Despite this improvement, data collected from 2009 to 2011 indicate a reduction in the number of P. sextuberculata nests, which could be related to overestimation of the number of nests in previous years; decrease in the nesting population; or natural phenomena. On the other hand, data show a gradual increase in the number of P. expansa nests. Our analysis suggest that data generated by a participatory monitoring system is limited to general reproductive data and more specific data collection must be accompanied by a technical team. Community-based conservation, despite its limitations, is a valid strategy for turtle conservation, as all nests would likely be preyed upon by humans, if nesting areas were not protected and guarded by local inhabitants.

The pirarucu counting method is a simplified stock assessment that has been used as the main parameter for establishing the annual fishing quotas in the management system of the Mamirauá and Amanã Reserves. In spite of the method’s directness, considering the recent expansion of managed fisheries, we cannot confirm that the counters thoroughly obey the original methodology. There is a concern of a technical nature, as the results of the counts directly influence the fishing quotas, and the lack of technical supervision or the inadequate application of the method are factors that can compromise the management system as a whole. This study aims to assess the counts that took place in six fishing environments of the Jarauá Sector, Mamirauá Reserve, and in four fishing environments of the area of the Pantaleão Fishing Agreement Complex, Amanã Reserve. We verified the consistency of the information resulting from the count, presented to the technical staff. To do this, we conducted recounts of juvenile and adult pirarucus in the same environments. In the Jarauá Sector we found significant differences in the counting results from Samaumerinha do Tucuxi and Curuçá do Centro. In Comprido do Maciel we found differences regarding the number of counted areas. In the sampled environments from the Pantaleão region we did not find significant differences between the counts. The results highlight the importance of creating assessment mechanisms for the counts, for the purpose of preventing possible alterations in the results that might influence the fishing quotas without a biological reason for justifying such quotas.

The common peacock bass, Cichla monoculus Spix; Agassiz, 1831, is a Neotropical cichlid native to the Amazon basin. Although it is highly valued for the quality of its flesh and intensely exploited by commercial fishing, representing the fourth most sold fish along the middle Solimões River in terms of landing statistics, little is known of the reproductive characteristics of this species in its natural habitat. The objective of this work was to reveal some morphological and histological aspects of gonadal development for this species. We also wanted to verify the gonadosomatic relation and allometric condition factor, and assess their use as reproductive indicators. Finally, we intended to reveal the fecundity and spawning type for some individuals of this species living in natural environments. In this study 73 females and 72 males of C. monoculus were utilized, from whom data were collected on total weight and total individual length. The gonads were later removed, weighed and macroscopically analyzed. To confirm this analysis tissue slices were taken from tissue cuts from 41 of the gonads. Based on the results of macroscopic and histological analyses five stages of development for females and four for males were identified. The ovaries were classified as immature, maturing, mature, spawned and at rest. The testicles were classified as immature, maturing, mature and spermiated. The females were found to be larger than the males, but the males were heavier. The gonadosomatic relation and the allometric condition factor were not considered good indicators of the reproductive status for this species. The spawning observed was of the total type, presenting an absolute average fecundity of 8,624 mature oocytes. Diameters of the vitellogenic oocytes varied from 1,210 μm to 3,000 μm. The total spawn, which is accompanied by oocytes with large diameters that have a large reserve of vitellus, is a factor that may favor the reproductive success of C. monoculus on the middle Solimões.

Compensatory density effects are key features of fish population dynamics that remain poorly understood in tropical river- floodplains. We investigated possible compensatory growth and reproductive processes for a river-floodplain population of Arapaima sp., an extinction-prone fish species of South America. Body growth was studied through analysis of ring patterns on the scales, and size and age at sexual maturity was studied through analysis of female gonads. Growth and maturity were compared for unmanaged conditions with relatively low population density (in 1990s) versus managed conditions with markedly higher density (in 2005-2006); between 1999 and 2005-2006, abundance increased 7.3 fold. Results contradict theoretical expectations for slower growth and delayed reproduction at higher population density. Total lengths of arapaima at low population density were significantly shorter for age classes 1-5 compared with lengths of those age classes at high population density (ancova, P < 0.0001 for both slopes and intercepts). Total length at 50% maturity (L50) only declined about 4% with increasing density (e.g., 164 cm at low density vs. 157 cm at high density). Apparent faster growth at high density and only a slight change in size at maturity resulted in fishes spawning at an earlier age with high density conditions (age 3 vs. age 4-5). We hypothesise that these patterns reflect compliance with minimum size limits of catch during the high density (managed) situation, where there was no harvest of immature fishes. Compliance with minimum size limits, thus, may have led to faster average body growth rate and earlier reproduction, which has greatly promoted population recovery.

Despite being an important member of neotropical fish assemblages, as well as a species with an unenviable reputation, little is known about the reproductive ecology of Red-bellied Piranha, Pygocentrus nattereri, in the wild. We tracked the reproductive activity of piranhas in the flooded forests of Mamiraua Reserve, Central Brazilian Amazon, for 2 years, in an investigation that included over 3,000 individual fish. Contrary to expectation piranhas had not one, but rather two annual reproductive seasons, tuned to water level fluctuation and the flooding pulse. Females were found to have up to 30,000 oocytes, little more than one third of which were mature and available for spawning in a single batch. Sexual maturation (of both males and females) occurred at around 160 mm. At this point sexually active individuals (of both sexes) became dark and lost most of their red coloration. Ontogenetic changes in habitat selection were strongly associated with the spawning behavior of mature adults. We also found that flooded marginal vegetation and marginal grasses inside lakes were the preferred spawning areas. In contrast, non-reproductive individuals were found in open water and under floating meadows.

This study examined the traditional knowledge of fishermen at Mamirauá Reserve about sex determination of pirarucus, Arapaima gigas Schinz 1822. We evaluated the criteria used for by fishermen in the sector Jarauá at Mamirauá Reserve for this determination, during the fisheries season, from October to November 2004. We analyzed responses of a group of about 15 fishermen collected in structured interviews regarding 109 individual pirarucus, 65 males and 44 females. From this sample, only 64 fish have their sex correctly predicted by the fishermen. Although the traditional knowledge of local fishermen is a key component of the sustainable fisheries of this species, this knowledge is not functional in all ranges and aspects, as in sex distinction. We found that the local fishermen evaluated are not able to recognize the sex of pirarucus, although some criteria applied for this purpose are consistent with their biology. The rates of correct forecasts for recognition of males and females were similar to those obtained by chance, even when the criteria applied were consistent, as the criterion “coloration”, which was significantly consistent for identification of males. Yet the group of fishermen interviewed in this study apparently did not apply this criterion correctly.

The Caiman Management Pilot Program in the Mamirauá Sustainable Development Reserve is coordinated by the government of the state of Amazonas. The initiative adheres to the legal framework for the use of natural resources in protected areas. Since 2004, three experimental culling events have taken place in the Jarauá sector of the Mamirauá Reserve. The latest event took place in December 2008, when 257 specimens were captured: 253 black caiman (Melanosuchus niger) and four spectacled caiman (Caiman crocodilus). Some data on surveys and specimen extraction in the latter experimental effort are hereby presented.

Summary 1. River system dynamics results in ecological heterogeneities that play a central role in maintain- ing biodiversity in riverine regions. In central Amazonia, large expanses of forest are seasonally flooded by nutrient-rich water (varzea forests) or by nutrient-poor water (igapoforests). Inunda- tion patterns and the nutrient load of floodwaters are perhaps the most important abiotic factors determining spatial ecological variations in lowland Amazonia, and so they are expected to strongly influence the structuring of animal communities. 2. We examined how inundation patterns and water-nutrient load influence the structure of neo- tropical assemblages of bats, one of the most diverse vertebrate groups in tropical forests. Bat assemblages were sampled with mist nets in central Brazilian Amazonia, across a mosaic of varzea, igapo´ , and non-flooding nutrient-poor terra firme forests in the low- and high-water seasons. 3. An ordination analysis clearly separated the assemblages of the three forest types, demonstrat- ing the structural relevance of both flooding and floodwater-nutrient load. Flooded forests had lower species richness because of the absence or rarity of species that make roosts out of leaves of understorey plants, and of those that feed on fruits of shrubs. Gleaning insectivores, also partly dependent on the understorey, were less abundant in flooded forests, but aerial insectivores more abundant, presumably because they benefited from a less cluttered foraging environment. These differences suggest that flooding affects bat assemblages mostly because it reduces the availability of niches associated with understorey vegetation, which tends to be sparser in flooded forests. 4. Nutrient-rich varzea forests had a bat biomass twice that of nutrient-poor igapoand unflooded forests. This difference was not only mostly due to a greater overall abundance of bats, but also attributable to a disproportionate higher abundance of large-bodied bat species. 5. We concluded that both flooding and floodwater-nutrient load are very important in the struc- turing of lowland Amazonian bat assemblages, with inundation mostly constraining the species composition of the assemblages, and water-nutrient load mostly influencing the abundance of spe- cies. The distinctiveness of bat assemblages associated with flooding emphasizes the need to pre- serve inundated forests, which are under particular pressure in Amazonia.

We examined seasonal patterns of spatial variation in understory bird assemblages across a mosaic of upland and floodplain forests in central Amazonia, where variation in flooding patterns and floodwater nutrient load shapes a marked spatial heterogeneity in forest structure and composition. Despite great differences in productivity due to flooding by either nutrient-rich “white waters” (varzea) or nutrient-poor “black waters” (igapo), bird assemblages in the two floodplain forest types were relatively similar, showing lower abundances than adjacent upland forests (terra firme) and sharing a set of species that were absent or scarce elsewhere. Species that breed in pensile nests overhanging water were abundant in floodplain forests, whereas species that feed on the ground were generally scarce. Flooding affected assemblage dynamics in floodplain forests, with some influx of ground-dwelling species such as ant-following birds from adjacent upland during the low-water season, and the occupation by riverine and aquatic species such as kingfishers during floods. Spatial configuration influenced the seasonal pattern of assemblage structuring, with movements from terra firme occurring primarily to adjacent igapo forests. No such influx was detected in varzea forests that were farther from terra firme and isolated by wide river channels. Results support the view that habitat heterogeneity created by flooding strongly contributes to maintain diverse vertebrate assemblages in Amazonia forest landscapes, even in the case of largely sedentary species such as understory forest birds. Including both upland and floodplain forests in Amazonia reserves may thus be essential to preserve bird diversity at the landscape scale.

Populations of two forms of uacaries, red and white, are found at the Mamirauá Sustainable Development Reserve (MSDR). Ayres (1986) notes that two skins of red uacaries were brought to Tefé (Amazonas state) from Auati-Paraná area, northern bank of Solimões river, inside the known geographical distribution of white uacaries, suggesting that a zone of contact between these two forms. The objective of this study was to gather information on the distribution of C. calvus at MSDR, both with interviews and direct observation. Parallel transects for active search were made at sites indicated by the inhabitants of the local communities. Nine communities confirmed the presence of white uacaries, while red uacaries were confirmed at seven communities. A small area of complete absence of the species was reported between Auati-paraná channel and Japurá river. A zone of contact between the two forms was indicated at Paraná do Aiupiá. For direct observation of the animals, 82.5 km were covered along Aiupiá channel, where white uacaries were observed in seven occasions, all at the right bank. Red uacaries were also spoted seven times, at the left bank. Further investigations at this area are being conducted in order to define the peripatry of both taxa, with big consequences to the conservation of the species.

In order to describe and better understand the aquatic environment of the várzea lakes at Mamirauá Reserve throughout the Amazonian hydrologic cycle, a sample of 11 of those lakes were chosen mainly for their accessibility and diversity. They were visited every season, for 2 consecutive years and morphological, limnological and biodiversity data was recorded. The aquatic macrophytes and the invertebrates (specially molluscs, crustaceans, arachnids, and the insect orders) found in its root zone were the taxonomic groups aimed. All information was used to group and ordinate the samples, to generate broad categories of lakes for Mamirauá Reserve. All sampled lakes proved to present high similarity with others, with the exception of one, more similar with the closest main river. However, two distinct groups were identified, mainly due to differences in conductivity of the water, its temperature and the presence or relative abundance of particular groups of invertebrates. These groups were consistent with the morphology of the lakes, the types of banks and levees, the type of riparian forest and the geomorphologic origin of the lake. This conclusion is useful for the evaluation of significance levels of aquatic environment at protected zones for the management of the reserve, and for the design of further ecologic research on the aquatic environment at the area.

Diel activity studies in fishes has had applications in the understanding of the species biology and are applied to the support of management actions in controlled environments. This study calculates fish abundance as diel activity indicator for O. bicirrhosum in four lakes of Mamirauá Sustainable Development Reserve during the dry season (September). The abundances along the day were associated with food ingestion, the sex and body size of individuals. Sim ultaneously to the fish catches, physico-chemical water param eters were measured. Total length, sex, gonad maturity stage and stom ach repletion degree (GR) were established for each fish. O. bicirrhosum showed two main activity diel periods associated with the main food ingestion rates and digestion. There were not detected significant differences between males and females activity along the day. The activity of O. bicirrhosum was negatively associated for three lakes physico-chemical factors. The picks of activity were associated positively with periods of food ingestion.

Summary Morphological information on the reproductive system allows the understanding of ecological and behavioural aspects of different species as well as supports the development of conservational strategies. Unfortunately, for many species, not enough relevant and precise information is available. In the present study, we describe for the first time the macroscopic and histological aspects of female genital organs and external female genitalia of Saimiri macrodon, Saimiri cassiquiarensis and Saimiri vanzolinii. We perform a comparison between these three peripatric species and investigate the possibility of their reproductive morphology to act as a factor of reproductive isolation. We have found that these species share many similarities in most of the analysed organs. Although some important differences were identified that may play an important role in the evolution of the components of the reproductive system of these species, those differences are not enough to compose a mechanism of reproductive isolation for these three species of Saimiri. The results of this study may be used to support the development of biotechnological approaches of reproduction and strategies for conservation programmes and management of threatened species of this genus, particularly S. vanzolinii, considered to be a vulnerable species to extinction.