Teses em Zoologia (Doutorado) - PPGZOOL/ICB

URI Permanente para esta coleçãohttps://repositorio.ufpa.br/handle/2011/3419

O Doutorado Acadêmico foi criado em 1999 e pertence ao Programa de Pós-Graduação em Zoologia (PPGZOOL) do Instituto de Ciências Biológicas (ICB) foi consolidado como um convênio entre Universidade Federal do Pará (UFPA) e Museu Paraense Emílio Goeldi (MPEG).

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Acesso aberto (Open Access)
Análise evolutiva da morfologia e ecologia em espécies continentais de lagartos do gênero Anolis daudin 1804 (Squamata : Polychrotidae)
(Universidade Federal do Pará, 2007-10-02) PINTO, Gabriel Silva; ÁVILA-PIRES, Teresa Cristina Sauer de; http://lattes.cnpq.br/1339618330655263
Acesso aberto (Open Access)
Aves da Floresta Nacional do Tapajós: composição, distribuição ecológica e efeitos da exploração madeireira de baixo impacto
(Universidade Federal do Pará, 2005) HENRIQUES, Luiza Magalli Pinto; OREN, David Conway; http://lattes.cnpq.br/5451507856491990
Acesso aberto (Open Access)
Avifauna do estado de Roraima: biogeografia e conservação
(Universidade Federal do Pará, 2005) SANTOS, Marcos Pérsio Dantas; SILVA, José Maria Cardoso da; http://lattes.cnpq.br/6929517840401044
Acesso aberto (Open Access)
Avifauna do estado do Acre: composição, distribuição geográfica e conservação
(Universidade Federal do Pará, 2009) SILVA, Edson Guilherme da; SILVA, José Maria Cardoso da; http://lattes.cnpq.br/6929517840401044
The Brazilian state of Acre borders Peru and Bolivia, and is located in the lowlands of the southwestern Amazon basin, close to the foothills of the Andes, in a region considered to be biologically megadiverse. Despite this, the region is still relatively poorly‐known in scientific terms, and is considered to be a priority for further biological surveys. With the aim of contributing to the understanding of the bird fauna of southwestern Amazonia, the principal objective of the present study was to evaluate these three questions: (a) How many and which bird species are found in Acre? (b) How are the species distributed in the state? and (c) What is the conservation status of the resident species? These questions were evaluated through a number of different approaches: (a) a comprehensive review of the literature; (b) field surveys over a two‐year period, including the recording and collection of voucher specimens; (c) production of distribution maps for each taxon (including species and subspecies); (d) distribution of the taxa among the state’s three major interfluvia or subregions (east, central, and west); (e) identification of zones of contact and hybridization, based on the distribution of parapatric species within the state; (f) estimation of the potential distribution of the taxa within the state of Acre, based on the extrapolation of the area occupied by that of each ecological unit (phytophysionomy) in which they were recorded; (g) assessment of the conservation goals for each resident taxon; and (h) a gap analysis, based on the overlap of the potential distribution maps with the state’s protected areas. The gap analysis was conducted with reference to three different scenarios: (a) inclusion of all the protected areas; (b) inclusion of only the fully‐protected area exclusive sustainable‐use units and indigenous reservations; and (c) including fully‐protected and sustainable‐use units, but excluding indigenous reservations. The literature review and surveys (historical and current fieldwork) began in August, 2005, and continued until December, 2007. At the end of this period, a total of 7.141 records of birds had been accumulated for the whole of the state of Acre. Of these, 4.623 are of museum specimens, 2.295 (49,6%) of which were collected during the present study. The presence of 655 biological species was confirmed for Acre, distributed among 73 families and 23 orders. One direct result of the study was the addition of five new species to the list of Brazilian birds. Fifty‐nine migratory species were also recorded, including 30 (50,8%) Nearctic and 18 (30,5%) austral migrants, as well as 11 (18,6%) considered to be intratropical migrants. Forty‐four of the species recorded in the study are endemic to the Inambari endemism center. Of the 556 taxa of forest birds resident in Acre, 405 (72,8%) are found in all three subregions, 56 (10,0%) were recorded only in the western subregion, 30 (5.3%) in the eastern subregion, whereas only three (0,5%) were exclusive to the central area. At least six pairs of sister taxa have an allopatric distribution in the state, while 15 sets of taxa present a parapatric distribution. Two zones of secondary contact (east‐west) and two possible hybrid zones (east‐west) were identified within the state. The gap analysis revealed that, under scenario (a), 87,1% of the taxa were fully protected (100% conservation target), and 12% were considered intermediate, that is, partially protected, whereas only 0.8% were completely unprotected. In scenario (b), by contrast, only 0,6% of the taxa were fully protected, 97.6% were partially protected, and 1,8% were totally unprotected. In the third scenario (c), 73,5% of taxa were fully protected, 25,5% partially protected, and only 0,8% completely unprotected. The principal conclusions reached in the present study were: (a) the Brazilian state of Acre has an extremely rich bird fauna, although the number of species recorded should still increase as new surveys are conducted; (b) the Purus and Juruá rivers do not constitute physical barriers to the dispersal of most bird species resident in Acre; (c) the existence of zones of secondary contact not related to the state’s principal river systems supports the conclusion that factors other than physical barriers determine the present‐day pattern of distribution of some of the resident bird taxa in Acre; (d) that the number of “gap” and “partial gap” bird species in Acre is very low when the full protected area network is considered, although this number increases with the exclusion of indigenous reservations, and in particular, sustainable‐use conservation units; and (e) the only species completely unprotected by the state’s conservation network are those restricted to the campina and campinarana ecosystems of western Acre, which indicates a clear need for the establishment of one or more conservation units in this region with the specific aim of protecting this distinct type of ecosystem.
Acesso aberto (Open Access)
A comunidade ictica e suas interrelacões tróficas como indicadores de integridade biológica na área de influencia do projeto hidrelétrico Belo Monte-Rio Xingu, PA
(Universidade Federal do Pará, 2004-04) CAMARGO-ZORRO, Mauricio; ISAAC, Victoria Judith; http://lattes.cnpq.br/3696530797888724
This study presents applied methodologies to better understand the dynamics of mechanisms characterizing a portion of the Xingu River, with respect to fish communities living in that environment. Through the study of the ichthyofauna it is aimed to verify various environmental standard patterns, in order to assess the current conservation state of a part of the Xingu River. Based on surveys of the local ichthyofauna conducted over seasonal variations, analyses were conducted at the specieS, population and trophic guild levels. With regards to the ecological population level, study of biological parameters such as individual growth rates, asymptotic body length, mortality rates and size at first maturity were good indicators for a better understanding of the life history of those fish groups. Therefore a trend was observed in which species of relatively small body size to followed a "r" type strategy, whilw species of larger body sizes would follow the "k" strategy tactics. From a functional point of view, it was verified that guild community structure is not only a good indicator of convergence patterns to similar ecosystems as like the Xingu River studied stretch, but also a tool to assess its conservation status. A steady- state ecosystem model for the medium Xingu River sector indicated that it is a system highly instable, and simultaneusly look like a mature seasonal system. An apparent seasonal restriction of food availability observed in the studied river section could imply optimum use efficiency and transfer of the trophic resources. A biogeographic study was undertaken based on species occurrence in order to conceptualise the River stretch comprised between the confluences of the Iriri and Xingu Rivers up to the vicinity of of the village Senador José Porfirio, in the Xingu basin. By means of this analysis, it was possible to demonstrate that the medium upstream of waterfalls) and lower (downstream) courses of the Xingu River are parts of two endemic areas. The low affinity of species composition observed in these two sectors is attributed to geographic variations in the landscape. Therefore, the boundaries of the waterfalls around the village of Belomonte and the influence of the Amazon River in the lower Xingu course could trigger differences in ichthyofaunal composition and species abundance when compared to the medium course of that river. Finally, the importance of maintaining all hydrologic connectivity is pointed out in order to maintan the unity of the system, from the headwaters to the mouth. Impacts on environmental processes and fish populations in the medium course of the Xingu River as a result of the eventual construction of the Belemonte hydroelectric dam are discussed.
Acesso aberto (Open Access)
Distribuição e conservação de aves migratórias neárticas da ordem Charadriiformes (famílias Charadriidae e Scolopacidae) no Brasil
(Universidade Federal do Pará, 2010) SERRANO, Inês de Lima; SILVA, José Maria Cardoso da; http://lattes.cnpq.br/6929517840401044
Despite the research efforts in recent years, some aspects of neartic Charadriidae and Scolopacidae migration in Brazil remained unknown. To detect the major movements patterns of these species in the country, local and regional scale studies had their data comprehensively organized. The identification of the patterns of neartic Charadriidae and Scolopacidae distribution and migration in the Brazilian territory is a major objective of this thesis. The data analysis also aims to develop conservation strategies for the envolved species. More specific objectives are the characterization of their main migratory routes and the identification of critical areas for their conservation, using the criteria proposed by the IBAs and KBAs; the assessment of the current state of conservation of critical areas accordingly to the National System of Units Conservation (SNUC); the assessment whether critical neartic shorebirds areas were designated as priority areas for biodiversity conservation in Brazil; and the use of Ramsar Convention and WHSRN criteria to identify critical areas for these species. The database was established from literature review, scientific collections of Brazilian and foreign museums, from birds banded in Brazil and U.S.; data provided by researchers from Brazil, Argentina and the United States, personal field data from the Pantanal (MS), coast of Maranhão and Rio Grande do Sul states coast. Nineteen of 24 species have important data set, the remaining 5 being either occasional or having little information in Brazil. The coastal areas have greater data concentration with lower coverage of inland areas. The western Amazon proved to be the least known in spite of some species use as a migratory route. The coast among the mouth of the Amazon and Sao Luis, Maranhão has been the main area in terms of numbers of neartic shorebirds. The coast of the state of Rio Grande do Sul was second. Not all individuals migrate every year to the northern hemisphere, as shown by the 15 species recorded year round in Brasil. Considering the global flyways, eight species were found using the Atlantic flyway and 10 the Mississippi flyway or the center of North America. The other six species may possibly use both flyways. Five flyways are proposed for neartic shorebirds in Brasil (Antas, 1983). During the northward migration some species have records in the Amazon region, period when possibly their habitats should be seasonnaly flooded. The pattern of arrival in the southward migration in Brazil is from August till October, increasing from September on. The northward migration occurs from mid March till April in most species. During the non breeding season there is a distributional pattern along the coast used by nine species. Seven other species use the inland pattern and five species are distributed both on the coast and in the inland, in the disperse pattern. We identified 260 critical areas using all species data. Amongst the identified KBAs, 72% are not within the SNUC. Overlap of the KBAs with the MMA´s Priority Areas for Conservation has shown 46% of major importance outside of this program. As much as 69 ACBs are eligible using the Ramsar Convention criteria, while 65 can be pinpointed using the WHSRN program criteria. As conclusions, it is necessary to improve the knowledge on biological processes envolving the maintainance the life cycle on the course of their annual migrations. Also the moult, body mass, sex ratio and age of migrant populations are aspects still insufficiently known for these species, either in Brazil or even in South America. There is an urgent research need of population estimates and trends, as many of these species have declining populations on global scale.
Acesso aberto (Open Access)
Diversidade beta entre taxocenoses de serpentes na margem direita do rio Amazonas, enfocando a história natural das serpentes do Parque Nacional (PARNA) da Amazônia, Pará, Brasil
(Universidade Federal do Pará, 2012) FROTA, Jossehan Galúcio da; COSTA, Maria Cristina dos Santos; http://lattes.cnpq.br/1580962389416378; PRUDENTE, Ana Lúcia da Costa; http://lattes.cnpq.br/1008924786363328
Acesso aberto (Open Access)
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.
Acesso aberto (Open Access)
Ecologia de lagos da planície inundada do baixo Tapajós: diversidade, estrutura de comunidade de peixes e percepções socieconômicas dos moradores de Alter do Chão, Santarém-PA
(Universidade Federal do Pará, 2005-10-07) COSTA, Luiz Rodolfo Ferreira da; BARTHEM, Ronaldo Borges; http://lattes.cnpq.br/4192105831997326
Acesso aberto (Open Access)
Ecologia do bagre Ageneiosus ucayalensis Castelnau, 1855 (Siluriformes: Auchenipteridae) em uma ria fluvial da Amazônia oriental
(Universidade Federal do Pará, 2015) OLIVEIRA, Valéria de Albuquerque; ROCHA, Rossineide Martins da; http://lattes.cnpq.br/4371300451793081; MONTAG, Luciano Fogaça de Assis; http://lattes.cnpq.br/4936237097107099
Acesso aberto (Open Access)
Efeitos do fogo recorrente na serrapilheira: consequências para artrópodes, decomposição e mineralização de carbono e nitrogênio em uma floresta de transição da Amazônia
(Universidade Federal do Pará, 2008) SILVEIRA, Juliana Miranda da; MOUTINHO, Paulo Roberto de Souza; http://lattes.cnpq.br/7277077476036269
Arthropods play an important role in ecosystem functioning, participating in nutrient cycling, decomposition and the breaking up and mixing of the leaf litter. Forest fires are increasing across the Amazon basin, and destroy the litter layer and kill the invertebrates that live within it. The objective of this thesis is to investigate how recurrent fires affect these processes, investigating the abundance and density of leaf-litter arthropods and the rate of decomposition of organic material and the mineralization of C and N, in a transitional Amazonian forest in the municipality of Querencia in the state of Mato Grosso, Brazil. The study was conducted in 50 ha of primary forest (500 x 1000 m) that was experimentally burned every year from 2004, and an unburned primary forest control of the same size. The arthropods were collected in 40 pitfall traps and 40 funnel Berlese traps, located randomly. The collections were undertaken in February, April (wet season), June, and August (dry season) of 2007, after the third experimental burning. The arthropods were identified to the level of Order, and the ants were identified to the level of Genera. The decomposition study was undertaken using 480 litter bags, randomly distributed with 240 in each plot, 4 months after the last burns. The litter bags were constructed with 2 mm nylon mesh (fine mesh), and 50% of them had 1 cm² holes cut in their sides (coarse mesh). 10g of dry leaves were placed in each litter bag, and 30 bags were collected from each plot every 2 months, equalling 2 collections in the wet season and 2 in the dry season. The litter bags were dried in an oven, and litter was weighted again to calculate decomposition. The difference between inicial and final weight showed the decomposition rate. Ten litter bags were selected randomly from every collection, mesh size, and plot, and subjected to a C and N analysis. The arthropods demonstrated strong seasonal differences. Springtails were less abundant and ants were more abundant in the dry season. Along with the seasonal effects, arthropods had diverse effects to the recurrent fires: Orthoptera were always more abundant in the burned plots in all post-fire samples when compared to controle plot. In general, macro-predators (ants, beetles, and others) were more abundant in the burned forest, while the ecosystem engineers and decomposers (cockroaches, Acaridae, and others) were less abundant in the burned forest, when compared to control plot. Ants were more diverse in the dry season, and also showed strong seasonal differences in composition. There was also a marked difference in ant diversity between the two plots, and fires favoured generalists ants. The decomposition rate in the burned forest were lower than in the control, and the fine mesh litter bags had a lower rate of decomposition than those with holes cut in their sides (coarse mesh). The level of C and N was also different between the plots, and the C/N ratio (indicating microbial activity) was stable over time in all post-fire collections, while the C/N ratio in the control plot declined gradually during the 4 collections. These results indicate that fire modifies the leaf-litter fauna, affecting the abundance and composition of various taxonomic groups. The fine mesh litter bags indicate that the exclusion of macroarthropods reduces the rate of organic matter decomposition and that microarthropods are more affected by fires. Fire also reduces the mineralization of C e N as C/N was stable in burned plot. Overall, this study shows that recurrent fires have strongly effects on leaf-litter fauna and nutrient cycling in Amazonian transitional forests.
Acesso aberto (Open Access)
Ephemeroptera (Insecta) no Brasil: estado da arte, amostragem, influências e distribuição
(Universidade Federal do Pará, 2015) FEITOZA, Yulie Shimano; JUEN, Leandro; http://lattes.cnpq.br/1369357248133029
In this thesis we aimed to contribute to the ecological knowledge about the Ephemeroptera order in Brazil in order to decrease Wallacean, Prestonian and Hutchinsonian shortfalls related to these organisms. For this purpose, we worked with bibliographic data and field sampling, which resulted in six chapters. We summarized bibliographic information about Brazilian Ephemeroptera studies in the first chapter and for the others, we used data from collections performed in Brazilian Amazonia, also for the last chapter, we have used both dataset from collected and bibliographic source. In the first chapter, we performed a scienciometric analysis about Ephemeroptera studies in Brazil, then we have found the main gaps: absence of studies in some Brazilian states and records of families, need of studies about phylogeny, need of improvement of taxonomic resolution in ecological studies, and deficit of knowledge about environmental variables affecting Ephemeroptera distribution. In the second chapter, we proposed new sampler (circular handnet) and sampling design (150-meters along streams) to be used in ecological studies. We tested in the third chapter the effectiveness of our own methodology, where applied to verify whether 15 subsamples are enough to represent mayflies fauna (instead 20 subsamples), also discontinuos sampling are better than continuous, and if the taxonomic resolution between species and genera are highly concordants. In the fouth chapter, the community was analysed in a regional scale, where we verified differences in environment structure of streams and species composition according to interfluves and scales (local or regional). In the fifth chapter, we tested if River Hypothesis is valid for mayflies communities in Brazilian Amazon, where we found the largest rivers acting as geographic barriers structuring mayflies distribution, as well as the connection of drainage basins also affected Ephemeroptera distribution. Finally, in the last chapter we made a study of case through a new approach of Threshold Indicator Taxa Analysis (TITAN). In this chapter, we found Miroculis as a genus associated to forested areas while Ulmeritoides was associatedrelated to oil palm plantation areas;With this thesis, we increased records and knowledge of Amazonian mayflies, by reducing gaps in relation to distribution (Wallacean deficit), abundance (Prestonian defict) and environmental answers from these organisms (Hutchinsonian deficit).
Acesso aberto (Open Access)
Estresse oxidativo de aves em clareiras naturais e sub-bosque na região Amazônica
(Universidade Federal do Pará, 2013) GOMES, Andreza de Lourdes Souza; SILVA, José Maria Cardoso da; http://lattes.cnpq.br/6929517840401044
Background: (Oxidative stress of birds in natural gaps and understory sites in the Amazon region). Studies that provide information about the distribution of birds in different phases of forest mosaic are essential for understanding the maintenance of biodiversity, since natural gaps play a central role on the structure and dynamics of tropical forest. Objectives: (a) to determine and compare the abundance and richness of frugivorous birds between the natural gap and understory habitats; (b) verify and associate the abundance of frugivorous birds with the availability of fruits in both areas; (c) to investigate the echophysiological interactions between the oxidative stress and the distribution of specimens of Dixiphia pipra and Willisornis poecilinotus, to determine which factors account for the variance of biomarkers of oxidative stress in these species. Methods: This study was carried out from November 2010 to October 2011 in terra firme forest sites at the National Forest of Caxiuanã, Melgaço, Pará, Brazil. Two different understory forest habitats were selected for sampling on the basis of physiognomies: natural tree fall gap and undisturbed forest. Twelve (12) sites were selected (6 natural gaps and 6 undisturbed continuous forests). In each site, groups of 10 mist nets were set at ground level which remained open from 6:00am to 2:00pm for two consecutive days, totaling six days each month. This procedure lasted for 12 months and the sampling effort totaled 23,040 mist net hours. All specimens captured were identified, marked with metal rings and kept in cotton bags. We collected blood, feces and regurgitation samples to determine the biomarkers of oxidative stress and the composition of the diet. The relationship between thiobarbituric acid reactive substances and the total antioxidant capacity was used as an index of oxidative stress. The vegetation structure was determined based on transects along the mist nets; the plants bearing fruits were identified and the total antioxidant capacity was determined in each plant. Results: During the period of the study 347 specimens of 21 species were sampled. The assemblage of frugivorous birds in natural gap is distinct from that of undisturbed forest sites. The species responsible for dissimilarity were Dixiphia pipra, Pipra rubrocapilla and Turdus albicollis. The richness of birds was similar in both sites, but the availability of fruits and the total capture index were higher in natural gaps. The primary frugivores (those whose feces or regurgitation always showed fruit pulp or seeds) occurred mainly in natural gaps, where the most abundant species was Dixiphia pipra. In addition, Pipra rubrocapilla was the most abundant species in undisturbed sites. Thirty-six (36) species of plants bearing fruits were recorded, and the abundance of frugivorous birds was significantly correlated with the number of plants bearing fruits in natural gaps, where the most common species of plants were: Psychotria colorata and Psychotria iodotricha. On the other hand, Faramea anisocalyx and Virola surinamensis were the most common species in undisturbed sites. The variation of biomarkers of oxidative stress in specimens presenting lek behavior varied with gender and to the site of sampling. In natural gaps, the adult males of Dixiphia pipra showed higher levels of oxidative stress. The high metabolic rate resulting of flight effort to avoid predators, courtship behavior to the female and territory defense, can increase the production of pro-oxidant compounds. However, the ingestion of fruits with high content of antioxidant compounds by male can minimize the deleterious effects of oxidative stress. The variance of oxidative stress of species that do not have organization in leks was associated only with the site of sampling. The specimens sampling in natural gaps showed higher levels of oxidative stress. This can be due to the increase in metabolic rate to avoid predators as well as new flight strategies for foraging.
Acesso aberto (Open Access)
Genética de populações de pirarucus (Arapaima gigas) da Reserva Mamirauá e considerações sobre estrutura genética para a espécie
(Universidade Federal do Pará, 2008-10-24) SILVA, Juliana Araripe Gomes da; SCHNEIDER, Horacio; http://lattes.cnpq.br/3621033429800270
The pirarucu (Arapaima gigas) is an important fishing resource in the Amazon which has been exploited since the XIXth century. There are indications of a decrease in population size in some parts of its distribution. Management is one of the strategies adopted to maintain fishing activity associated to the conservation of the species. We evaluate aspects of pirarucu populations in two places in the Mamirauá Reserve (Jarauá and Maraã), and compare these populations with those of Santarém and Tucuruí, analyzing their genetic variability and structure. In order to achieve this, seven microsatellite loci were genotyped for 463 pirarucus from Mamirauá Reserve collected along five years. Our results show a greater genetic diversity for this population in comparison to populations from Santarém and Tucuruí. Analyses indicate that management has been ecologically efficient, since there were no significant change in genetic diversity over the five years of study. Lateral migration, associated with a possible standardized return to lakes without spacial fidelity seems to have great importance for local genetic admixture. However, this admixture is limited in space, with a small degree of genetic differentiation seem between pirarucus from Jarauá and Maraã. When including more distant localities to the analysis, the differentiation is greater though geographic distance cannot explain all of this. We believe that a population decline in intermediate localities, probably caused by overexploiting is influencing the connectivity among the localities studied.
Acesso aberto (Open Access)
Heterogeneidade ambiental e diversidade de peixes de riachos na Amazônia
(Universidade Federal do Pará, 2017-09-07) BENONE, Naraiana Loureiro; MONTAG, Luciano Fogaça de Assis; http://lattes.cnpq.br/4936237097107099; ESPOSITO, Maria Cristina; http://lattes.cnpq.br/2112497575917273
Amazon streams are highly heterogeneous systems that encompass a remarkable diversity. Due to the increasing threats to these systems, it is necessary to understand how ecological process in natural areas affect streams and their fish biota. This thesis was divided in three chapters and aims to answer the following questions: 1) How much do catchment variables affect the physical habitat of small streams in the Amazon? 2) What is the relative contribution of environmental and spatial variables on taxonomic and functional alpha and beta diversity of stream fish? 3) How much are distinct components of biodiversity (species diversity, taxonomic distinctness, and functional diversity) congruent and how much can they be predicted from catchment variables? Fifty seven streams were sampled across six river basins in the Amazon region. For environmental characterization, a standardized protocol was used to obtain more than 140 local variables, and 11 catchment variables were obtained from aerial images. Fish assemblages were sampled with hand nets during a six-hour period. Stream catchments were divided in two groups based on altitude and slope. These two variables influenced streams habitats, regulating flow velocity and the types and proportions of substrates. The taxonomic and functional patterns of fish assemblages were affected by environmental filters operating at the catchment scale. Nonetheless, variables at the local scale were particularly important to taxonomic and functional alpha diversity. Despite the significant role of environmental filters, limited dispersal was the main driver of variation in fish diversity, indicating a strong biogeographic factor. Finally, various components of diversity exhibited intermediate congruence, which suggests that no single component can describe patterns of fish diversity. In addition, catchment variables alone could not accurately predict diversity patterns, and therefore it is recommended that additional explanatory variables, including descriptors of local environmental conditions, are important to include in studies of stream fish diversity.
Acesso aberto (Open Access)
História natural das raias de água doce (Chondrichthyes: Potamotrygonidae) na Ilha de Marajó (Pará- Brasil)
(Universidade Federal do Pará, 2008) ALMEIDA, Mauricio Pinto de; BARTHEM, Ronaldo Borges; http://lattes.cnpq.br/4192105831997326
The present study was on the natural history of freshwater stingrays species (Potamotrygonidae) of the Marajó Island. It was carried out in four sampling points (Afuá, Lago Arari, Muaná and Soure) in dry, rainy and transition seasons, in 2005 throughout 2007. Five species were captured in this area, Plesiotrygon iwamae, Paratrygon aiereba, Potamotrygon motoro, Potamotrygon orbignyi and Potamotrygon scobina and two other new species, presently in description. Data on the Potamotrygonidae family composition and distribution were obtained, such as frequency of occurrence, biomass and fishery gear selectivity. Data on the reproduction and feeding of the species were described for this region, with emphasis on Potamotrygon motoro.
Acesso aberto (Open Access)
História natural e ecologia das serpentes da Floresta Nacional de Caxiuanã e áreas adjacentes, Pará, Brasil
(Universidade Federal do Pará, 2008) MASCHIO, Gleomar Fabiano; MARTINS, Marlúcia Bonifácio; http://lattes.cnpq.br/8882047165338427; PRUDENTE, Ana Lúcia da Costa; http://lattes.cnpq.br/1008924786363328
The search for patterns of community structure and composition is essential to provide information which allows the sustained management of species populations and monitoring of antropic activities. Despite the fact that Neotropical region harbors an enormous diversity of species and complex ecological interactions, very little information is available on snake assemblages. Therefore, the processes responsible for community organization are not well understood. In Brazil, several studies were conducted to analyze the factors responsible for the patterns of distribution and interactions among snake species. In order to identify the factors that determine those patterns and which affinities (ecological and or historical) those species share, a study of the local taxocenose of snakes was performed in the Floresta Nacional de Caxiuanã and adjacent areas, from 2005 to 2006. Four sampling methods were used employed: time constrained search, local collectors, incidental encounters, and pitfall traps with drift fences, in five areas (IBAMA and Caquajó in the Floresta Nacional de Caxiuanã; Marinaú, Enseada and Mojuá located in adjacent areas to the Floresta Nacional de Caxiuanã). A total of 378 specimens of snakes within five families, 35 genera and 50 species were registered. Considering the records of species obtained in this study and those from previous studies, the local number of snake species increases from 63 to 69 species. The methods that best revealed the number of individuals were time constrained search (199/378) and local collectors (159/378). Incidental encounters (11/378) and pitfall traps with drift fences (9/378) were less representative. The estimated richness (Jackknife 1) from PLT data was 56 (+or– 4) species. The composition of snake species in the studied area shows higher similarity with taxocenoses of other Amazon areas. Most abundant species, as revealed by time constrained searches, were Imantodes cenchoa, Corallus hortulanus and Leptodeira annulata. All methods showed Bothrops atrox, Imantodes cenchoa and Corallus hortulanus as most representative. The areas under high antropic pressures located out of the National Forest showed lower abundance and richness when compared to protected areas in there. Nine potentially specialist species were recorded: Lachesis muta (small mammals), Atractus schach (earthworms), Dipsas catesbyi (mollusks), Helicops trivitatus and Hydrops triangularis (fish), Siphlophis compressus (lizards), Xenopholis scalaris, Taeniophallus brevirostris (anuran) and Tantilla melanocephala (centipedes). The items most frequently consumed were lizards, anurans and small mammals. The snake species primary or exclusively diurnal represent the larger percentage. Most species analyzed present non seasonal reproductive period, possibly as a result of no significant differences in the mean temperature throughout the year. The taxocenose of snake species in the Floresta Nacional de Caxiuanã and neighboring areas is formed by groups of species that share similar patterns of feeding and daily activities. Besides several ecological factors such as temperature and pluviometric averages and biome structure, historical factors (such as morphological adaptations of snake species) influence on sbake taxocenose composition in the Floresta Nacional de Caxiuanã and adjacent areas. Thus, more studies on the ecology and natural history of snakes must be continuously conducted in order to characterize novel patterns of distribution of snake species in different biomes.
Acesso aberto (Open Access)
Influências dos ninhos de saúva (Formicidae: Attini) na nutrição, crescimento e proteção da vegetação contra o fogo, em uma floresta de transição Amazônia-Cerrado
(Universidade Federal do Pará, 2008) CARVALHO, Karine Santana; STERNBERG, Leonel; http://lattes.cnpq.br/2673570808369028; MOUTINHO, Paulo Roberto de Souza; http://lattes.cnpq.br/7277077476036269
The leaf-cutting ant nests are important natural disturbances which may create mosaics of certain types of vegetation and affect the structure and composition of Neotropical ecosystems. So, this study evaluated the effects of leaf-cutting ant nests (Atta spp.) on dynamic of vegetation growth in a Amazon-Cerrado transitional forest submitted to subsequent fire events, in south Amazon basin, Mato Grosso State, Brazil. Specifically, it was evaluated the effects of the nests on: (1) vegetation growth and nutrition; (2) vegetation protection against fire and (3) the forest regeneration pos-fire. The nests and associated vegetation (within a 10-meter radius of the nests) established in 150-hectare areas of transitional forest were mapped and monitored in order to determine such effects. These areas subdivided in 50-ha parts with different treatments: triannual fires, annual fires and fire protection (control) take part in the project “Savannization” coordinated by Amazon Environmental Research Institute – IPAM. The experiments about the effects of the nests on vegetation growth and nutrition indicated that plants next the nests have a facilitated nutrient absorption and therefore they present a higher foliar concentration of Phosphorus. Consequently, it was registered a higher growth in diameter of stem to these plants when compared to those far from the nests. The nests worked as active firebreaks (due to accumulation of land on mound resulting from leaf-cutting ants diggings) reducing the total burned area around them, mainly in areas with high number of nests and protecting the surrounding vegetation from the mortality by fire. In opposition to these benefits, it was verified higher herbivory of seedlings and the removal of seeds by leaf-cutting ants in areas with high density of active colonies, a result which compromise the early stages of pos-fire forest succession. This study shows the importance of leaf-cut ants in the redistribution and nutrient recycling and demonstrates, for the first time, the vegetation protection against fire, by their nests. On the other hand, it also shows that anthropic disturbances, such as fire, increase the leaf-cut ant population. This can stop the pos-fire forest regeneration. Considering this study, it can predict that natural environments may have the vegetation growth accelerated due to the presence of leaf-cut ant nests, but in disturbed environments the action of leaf-cut ants may be the main threat to the original vegetation regeneration. So, it can conclude that the effects (beneficial or harmful) of the leaf-cut ants depend on the level of disturbance or maturity of biome in which their nests are established.
Acesso aberto (Open Access)
Interação de Ucides cordatus Linnaeus, 1763 em manguezais da Ilha de Marajó: uma abordagem ecológica
(Universidade Federal do Pará, 2012) GOMES, Cleidson Paiva; FERNANDES, Marcus Emanuel Barroncas; http://lattes.cnpq.br/8943067124521530
The present study was carried out in the mangroves of Soure, Marajó Island, Pará, Brazil, where the great amount of freshwater intake allows the development of transition zones estuary/river defining the geobotanic limits for mangroves in the state of Pará and, hence, for the leaf-removing mangrove crab (Ucididae). For an ecological approach on the interaction between U. cordatus and mangrove forests the following issues were investigated: i) the relationship between the population characteristics of U. cordatus and different transition levels along the gradient of vegetation between mangrove forests and tidal valley forests, ii) the influence of environmental factors of such transition zones on patterns of size and density of U. cordatus population, iii) the impacts of herbivory of U. cordatus on the seedlings production and the possible effects on recruitment process of these seedlings for mangrove forests. Study sites were classified according to the transition level of the tidal várzea forests, and these values correlated with density and size values of U. cordatus population. In each study site the availability of food by litterfall rates, salinity, and indicators of fishing activities on these areas were determined. The impact of U. cordatus on the recruitment of mangrove stands was evaluated by estimating the rate of herbivory and predation on propagules. The results reveal that in the zone of "high transition" local conditions seem to limit U. cordatus stocks, showing that the density of this species population is much lower compared to those recorded in the "low transition" zone. However, areas of high transition offer more favorable conditions for development of the leaf-removing mangrove crab populations, especially with regard to the variability and availability of food and protection from human action in the region. The indicators of fishing activity on U. cordatus revealed that the mangrove forests of the lower transition zone are more subject to overexploitation, mainly for ease of access. The main via of impact on propagules was the consumption rate of 60%, being the rate of export of propagules by tides of only 1%, thus less relevant. U. cordatus may be considered the most important impact agent on the propagules production of these mangrove forests without showing selectivity by size or maturity of seedlings, being important in the regulation of recruitment rates and, hence, in the population dynamics of Rhizophora’s trees in the mangrove forests on the coastal zone of Marajó Island, in the Brazilian Amazon.
Acesso aberto (Open Access)
Morfometria e descrição de otólitos de dourada (Brachyplatystoma rosseauxii) (Castelnau, 1855) e de piramutaba (B. vaillantii) (Valenciennes, 1840) (Siluriformes: pimelodidae) e verificação de anéis de crescimento em otólitos de juvenis de dourada e de piramutaba na Ilha de Colares - Baía de Marajó-PA
(Universidade Federal do Pará, 2008-10-09) PIRKER, Lilianne Esther Mergulhão; BARTHEM, Ronaldo Borges; http://lattes.cnpq.br/4192105831997326
The dourada (Brachyplatystoma rousseauxii) and the piramutaba (B. vaillantii), two migratory freshwater catfishes, are exploited by both traditional and industrial fishery in the Amazonian. They are very important for the commercial fishery in this region and their stocks are currently sobrexploted. However there is a lack of information concerning the biology and ecology of juvenile stages of these catfishes in the scientific literature. In population dynamics studies, the correct age estimate influences the growth parameters, which are important to evaluate stocks. The studies of age determination are usually made using sub-adults and adults specimens. The juveniles are not analyzed and their age is back-calculated. Which could result in an error estimate. The aims of the present research were: (1) to describe and estimate the relation between the lapilli otoliths morfometric measurements and the body measurements of dourada and piramutaba, and (2) to examine the occurrence of the first growth rings in the juvenile specimens. The morfometric and descriptive studies were carried out using otoliths from dourada and piramutaba juveniles, sub-adults and adults collected in the municipalities of Colares (PA), Almeirim (PA), Santarém (PA), and Manaus (AM), in the District of Mosqueiro (PA), and in the Amazon estuary. The period of collection was different for each local, to September of 1996 to January of 2006. The following relations were estimated: furcal length from specimens (LF) x total weight from specimens (WT); LF x maximum otolith length (MOL); LF x maximum otolith width (MOW); LF x otolith total weight (OWT); WT x MOL; WT x MOW and WT x OWT. The estimated equations were: Dourada: WT = 9.5 x 10-6 x LF 3.0279, LF = 25.259 * MOL1.1571, LF = 40.626 * MOW1.2127, LF = 840.419 * OWT0.4077, WT = 0.125 * MOL3.6547, WT = 0.568 * MOW3.8294, WT = 7549.98 * OWT1.2651; Piramutaba: WT = xxx 5.4 x 10-6 x LF 3.1441, LF = 31.871 * MOL1.3381, LF = 55.852 * MOW1.3722, LF = 1641.064 * OWT0.4686, WT = 0.3127 * MOL4.1857, WT = 1.823 * MOW4.2788, WT = 66675.977 * OWT1.4508. In the descriptive study, the lapilli of dourada and piramutaba were classified in the following categories according to their development and specimens LF: dourada I (60 a 80 mm), dourada II (80 a 110 mm), dourada III (110 a 210 mm), piramutaba I (65 a 80 mm), piramutaba II (80 a 110 mm), and piramutaba III (110 a 190 mm). In the lapillus ring reading study, only the juveniles specimens £ 200 mm LF were used. In the Marajó bay, douradas and piramutabas with 175.03 mm and 171.03 mm mean LF, respectively, showed the first growth ring. Both species were between nine and twelve months old when they showed the first growth ring. The mean rays of the first hyaline ring in the transversal cut of dourada’s and piramutaba’s lapillus were 0.36 mm (± 0.03) and 0.33 mm (± 0.01), respectively. The mean total ray of the lapillus transversal cut was 0.64 mm (± 0.14) in dourada and 0.53 mm (± 0.09) in piramutaba. The estimated equation relating the total ray of the lapillus transversal cut of douradas juveniles with its LF was LF = 248.589 * Rt1.1901. The estimated equation for piramutaba was LF = 400.494 * Rt1.7178. Douradas and piramutabas 60-70 mm LF were three to six months old, 70-110 mm LF were six to nine months old, and 110-200 mm LF were nine to twelve months old.