Lower Amazon Research Articles

Natural Leishmania (Viannia) spp. infections in phlebotomine sand flies (Diptera: Psychodidae) from the Brazilian Amazon region reveal new putative transmission cycles of American cutaneous leishmaniasis.

In Amazonian Brazil the etiological agents of American cutaneous leishmaniasis (ACL) belong to at least seven Leishmania species but little is known about the putative phlebotomine sand fly vectors in different biomes. In 2002–2003 a survey of the phlebotomine fauna was undertaken in the “Floresta Nacional do Tapajós”, Belterra municipality, in the lower Amazon region, western Pará State, Brazil, where we recently confirmed the presence of a putative hybrid parasite, L. (V.) guyanensis × L. (V.) shawi shawi. Sand flies were collected from Centers for Disease Control (CDC) light traps, Shannon traps and by aspiration on tree bases. Females were dissected and attempts to isolate any flagellate infections were made by inoculating homogenized midguts into Difco B45 medium. Isolates were characterized by monoclonal antibodies and isoenzyme electrophoresis. A total of 9,704 sand flies, belonging to 68 species or subspecies, were collected. Infections were found in the following sand flies: L. (V.) naiffi with Psychodopygus hirsutus hirsutus (1) and Ps. davisi (2); and L. (V.) shawi shawi with Nyssomyia whitmani (3) and Lutzomyia gomezi (1). These results provide strong evidence of new putative transmission cycles for L. (V.) naiffi and L. (V.) s. shawi.

A new Centromochlus Kner, 1858 (Siluriformes: Auchenipteridae: Centromochlinae) from the transition between Amazon floodplain and Guiana shield, Brazil

ABSTRACT Species of Centromochlus are widely distributed in South America, with records for major basins such as the Amazon and Orinoco, rivers draining the Guiana Shield such as the Essequibo, Courantyne (Corantijn), Coppename, Maroni, and Oyapock, and Brazilian Shield drainages as upper Paraná and São Francisco. In the last four years, three species of Centromochlus have been described, raising the total number of valid species to sixteen. The new species of Centromochlus described herein is diagnosed by having black ground color sharply delimited from a white underside by conspicuous wavy border. The new species is recorded from the Nhamundá, left bank tributary to the lower Amazon that drain from the Brazilian portion of the Guiana Shield. Although apparently similar to some Tatia species (e.g. Tatia musaica , T. carolae and T. melanoleuca ), the new species possess two conditions of the Weberian apparatus otherwise observed only in Centromochlus heckelii and C. existimatus among centromochlin catfishes. The new Centromochlus comprises small catfishes with adults ranging from 48 to 57 mm SL.

Dual-season and full-polarimetric C band SAR assessment for vegetation mapping in the Amazon várzea wetlands

Abstract This study answered the following questions: 1) Is polarimetric C-band SAR (PolSAR) more efficient than dual-polarization (dual-pol) C-band SAR for mapping varzea floodplain vegetation types, when using images of a single hydrological period? 2) Are single-season C-band PolSAR images more accurate for mapping varzea vegetation types than dual-season dual-pol C-band SAR images? 3) What are the most efficient polarimetric descriptors for mapping varzea vegetation types? We applied the Random Forests algorithm to classify dual-pol SAR images and polarimetric descriptors derived from two full-polarimetric Radarsat-2 C-band images acquired during the low and high water seasons of Lago Grande de Curuai floodplain, lower Amazon, Brazil. We used the Kappa index of agreement (κ), Allocation Disagreement (AD) and Quantity Disagreement (QD), and Producer's and User's accuracy measurements to assess the classification results. Our results showed that single-season full-polarimetric C-band data can yield more accurate classifications than single-season dual-pol C-band SAR imagery and similar accuracies to dual-season dual-pol C-band SAR classifications. Still, dual-season PolSAR achieved the highest accuracies, showing that seasonality is paramount for obtaining high accuracies in wetland land cover classification, regardless of SAR image type. On average, single-season classifications of low-water periods were less accurate than high-water classifications, likely due to plant phenology and flooding conditions. Classifications using model-based polarimetric decompositions (such as Freeman–Durden, Yamaguchi and van Zyl) produced the highest accuracies (κ greater than 0.8; AD ranging from 7.5% to 2.5%; QD ranging from 15% to 12%), while eigenvector-based decompositions such as Touzi and Cloude–Pottier had the worst accuracies (κ ranging from 0.5 to 0.7; AD greater than 10%; QD smaller than 10%). Vegetation types with dense canopies (Shrubs, Floodable Forests and Emergent Macrophytes), whose classification is challenging using C-band, were accurately classified using dual-season full-polarimetric SAR data, with Producer's and User's accuracies between 80% and 90%. We conclude that full polarimetric C-band imagery can yield very accurate classifications of varzea vegetation (κ ~ 0.8, AD ~ 3% and QD ~ 10%) and can be used as an operational tool for forested wetland mapping.

Food consumption as an indicator of the conservation of natural resources in riverine communities of the Brazilian Amazon.

The present study analyzed and compared the daily consumption of foods of animal origin in eleven communities of the Lower Amazon, Trombetas and Purus Rivers, representing three different management systems and levels of conservation in the Brazilian Amazon. All food items of animal origin were weighed by at least 10% of the families in the study communities during a week in each period of the flood cycle between 2006 and 2008. Fish was the most important food, and was consumed during six days of the week, with an average rate of 169 kg.person(-1).year(-1). Game was second in importance, with 37 kg.person(-1).year-(1). This yearly rate of fish consumption is one of the highest in the world and is almost double the minimum recommended by the World Health Organization. The dietary patterns reflect both the isolation of the communities from large urban centers and the better preservation of the local environments due to the existence of protected areas. Environmental degradation may thus have effects on the health and food security of local populations. The study emphasizes the need for the implementation of public policies and participative management initiatives.

Abiotic variability among different aquatic systems of the central Amazon floodplain during drought and flood events.

This paper examines water properties from lakes, (depression lakes, sensu Junk et al., 2012), channels (scroll lakes with high connectivity, sensu Junk et al., 2012) and paleo-channels (scroll lakes with low connectivity-sensu Junk et al., 2012, locally called ressacas) located in Mamirauá Sustainable Development Reserve, in Central Amazon floodplain, Amazonas, Brazil. We analysed surface temperature, conductivity, pH, dissolved oxygen, turbidity, transparency, suspended inorganic and organic matter, chlorophyll-a, pheophytin, total nitrogen, total phosphorus, organic and inorganic carbon in 2009 high water phase, 2009 and 2010 low water phases. Multivariate statistical analyses of 24 aquatic systems (6 ressacas, 12 lakes and 6 channels, 142 samples) were applied to the variables in order to: 1) quantify differences among aquatic system types; 2) assess how those differences are affected in the different phases of the hydrological year. First, we analysed the entire set of variables to test for differences among phases of the hydrological year and types of aquatic systems using a PERMANOVA two-way crossed design. The results showed that the all measured limnological variables are distinct regarding both factors: types of aquatic systems and hydrological phases. In general, the magnitude and amplitude of all variables were higher in the low water phase than in the high water phase, except for water transparency in all aquatic system's types. PERMANOVA showed that the differences between aquatic system's types and hydrological phases of all variables were highly significant for both main factors (type and phase) and for the type x phase interaction. Limnological patterns of Amazon floodplain aquatic systems are highly dynamic, dependent on the surrounding environment, flood pulse, main river input and system type. These patterns show how undisturbed systems respond to natural variability in such a diverse environment, and how distinct are those aquatic systems, especially during the low water phase. Aquatic systems in Mamirauá floodplain represent limnological patterns of almost undisturbed areas and can be used as future reference for comparison with disturbed areas, such as those of the Lower Amazon, and as a baseline for studies on the effects of anthropogenic influences and climate change and on Amazon aquatic ecosystem.

Flood pulse effects on multispecies fishery yields in the Lower Amazon.

Seasonally fluctuating water levels, known as ‘flood pulses’, control the productivity of large river fisheries, but the extent and mechanisms through which flood pulses affect fishery yields are poorly understood. To quantify and better understand flood pulse effects on fishery yields, this study applied regression techniques to a hydrological and fishery record (years 1993–2004) for 42 species of the Amazon River floodplains. Models based on indices of fishing effort, high waters and low waters explained most of the interannual variability in yields (R2=0.8). The results indicated that high and low waters in any given year affected fishery yields two and three years later through changes in fish biomass available for harvesting, contributing 18% of the explained variability in yields. Fishing effort appeared to amplify high and low water effects by changing in direct proportion to changes in fish biomass available for harvesting, contributing 62% of the explained variability in yields. Although high waters are generally expected to have greater relative influence on fishery yields than low waters, high and low waters exerted equal forcing on these Amazonian river-floodplain fishery yields. These findings highlight the complex dynamics of river-floodplain fisheries in relation to interannual variability in flood pulses.

Rhinebothrium jaimei sp. n. (Eucestoda: Rhinebothriidea: Rhinebothriidae): a new species from Neotropical freshwater stingrays (Potamotrygonidae).

Neotropical freshwater stingrays (Batoidea: Potamotrygonidae) host a diversity of parasites, including some, like their hosts, that are marine-derived. Among the parasites of potamotrygonids, the cestode fauna is the most diverse, with multiple genera having been reported, including genera endemic to the freshwaters of the Neotropics and genera that have cosmopolitan distributions. Recent efforts have been made to document the diversity of cestodes of this host-parasite system and to refine the taxonomy of parasite lineages. The present study contributes to our knowledge of Rhinebothrium Linton, 1890, a diverse cosmopolitan genus of rhinebothriidean cestode, with 37 species reported from marine batoids, one species from a freshwater stingray in Borneo and six species from potamotrygonids. Rhinebothrium jaimei sp. n. is described from two species of potamotrygonids, Potamotrygon orbignyi (Castelnau) (type host) and Potamotrygon scobina Garman, from Bahía de Marajó of the lower Amazon region. It can be distinguished from most of its marine congeners via multiple attributes, including its possession of two, rather than one, posteriormost loculi on its bothridia and the lomeniform shape of its bothridium that is wider anteriorly. In addition, R. jaimei sp. n. can be distinguished from the six Rhinebothrium species described previously from potamotrygonids based on a unique combination of morphological features. Despite extensive stingray cestode sampling efforts throughout all major Neotropical river systems, we found that unlike most species of potamotrygonid Rhinebothrium species, which are widespread, R. jaimei sp. n. is restricted to the Bahía de Marajó. The discovery of this new species of Rhinebothrium in Bahía de Marajó, an area in which potamotrygonids occur sympatrically with some species of euryhaline batoids (e.g. Dasyatis spp.) and share some trophic resources, suggest that modern ecological processes may be contributing to the distribution patterns of cestodes infecting potamotrygonids.

Trace gas fluxes from intensively managed rice and soybean fields across three growing seasons in the Brazilian Amazon

The emission of gases that may potentially intensify the greenhouse effect has received special attention due to their ability to raise global temperatures and possibly modify conditions for life on earth. The objectives of this study were the quantification of trace gas flux (N2O, CO2 and CH4) in soils of the lower Amazon basin that are planted with rice and soybean, and the relation of this flux to soil physical and chemical parameters and to precipitation. This study was conducted in agricultural fields planted with rice (Oryza sativa) and soybean (Glycine max), located near the cities of Belterra and Santarem in western Para State, Brazil, during the production years of 2005 to 2007. Measurements were done using static chambers in the field, and samples were analyzed by gas chromatography in the laboratory. Statistical analysis was conducted to determine variation in gas flux in both crops, and the results show that CO2 flux varied between 305 and 227 mg-C m-2 h-1 under rice, and 243 and 156 mg-C m-2 h-1 under soybean. Flux of N2O under rice varied between 4.5 and 20.4 µg-N m-2 h-1, and under soybean flux variation was between 4.0 and 9.4 µg-N m-2 h-1. Variation in flux of CH4 under rice was between 5.1 and 14.0 µg-C m-2 h-1, and under soybean it was 0.4 and 1.2 µg-C m-2 h-1. These results demonstrate that, during the study period, the rice crop had higher flux for all trace gases than the soybean crop. Key words: Amazon region, trace gas, crops.

Metagenomic and metatranscriptomic inventories of the lower Amazon River, May 2011.

BackgroundThe Amazon River runs nearly 6500 km across the South American continent before emptying into the western tropical North Atlantic Ocean. In terms of both volume and watershed area, it is the world’s largest riverine system, affecting elemental cycling on a global scale.ResultsA quantitative inventory of genes and transcripts benchmarked with internal standards was obtained at five stations in the lower Amazon River during May 2011. At each station, metagenomes and metatranscriptomes were obtained in duplicate for two microbial size fractions (free-living, 0.2 to 2.0 μm; particle-associated, 2.0 to 297 μm) using 150 × 150 paired-end Illumina sequencing. Forty eight sample datasets were obtained, averaging 15 × 106 potential protein-encoding reads each (730 × 106 total). Prokaryotic metagenomes and metatranscriptomes were dominated by members of the phyla Actinobacteria, Planctomycetes, Betaproteobacteria, Verrucomicrobia, Nitrospirae, and Acidobacteria. The actinobacterium SCGC AAA027-L06 reference genome recruited the greatest number of reads overall, with this single bin contributing an average of 50 billion genes and 500 million transcripts per liter of river water. Several dominant taxa were unevenly distributed between the free-living and particle-associated size fractions, such as a particle-associated bias for reads binning to planctomycete Schlesneria paludicola and a free-living bias for actinobacterium SCGC AAA027-L06. Gene expression ratios (transcripts to gene copy ratio) increased downstream from Óbidos to Macapá and Belém, indicating higher per cell activity of Amazon River bacteria and archaea as river water approached the ocean.ConclusionThis inventory of riverine microbial genes and transcripts, benchmarked with internal standards for full quantitation, provides an unparalleled window into microbial taxa and functions in the globally important Amazon River ecosystem.Electronic supplementary materialThe online version of this article (doi:10.1186/s40168-015-0099-0) contains supplementary material, which is available to authorized users.

Reproductive biology of Macrobrachium surinamicum (Decapoda: Palaemonidae) in the Amazon River mouth

Macrobrachium surinamicum is an indigenous prawn distributed from the lower Amazon and Tocantins river basins to Venezuela in the Orinoco Delta region. It is common bycatch fauna of Macrobrachium amazonicum artisan fishing in the states of Pará and Amapá. The aim of this study was to investigate aspects on reproductive biology (reproductive period, size of sexual maturity population, fecundity, reproductive output and recruitment) of M. surinamicum from four important areas to artisanal prawn fishing located at the Amazon River mouth (Amapá and Pará). The specimens were captured using 20 handcrafted traps called "matapi". A number of 675 prawns were captured, 258 males, 409 females and eight juveniles, resulting in 1:1.6 (Male: Female) sex ratio. The reproductive peak period occurred from March to July, coinciding with the higher rainfall period. The juvenile prawn occurred only in May and July. Total length of egg-bearing females ranged from 12.12 to 38.30 mm, with mean female length at first maturity (L50) of 23.7 mm. Fecundity increased with prawn size and varied between 174 and 1780 eggs per female. Mean egg volume increased gradually from 0.031 (Stage I) to 0.060 mm³ (Stage III) during embryogenesis. Macrobrachium surinamicum depends on brackish water to complete the larval development. Irrespective of female size, reproductive output of M. surinamicum varied between 4.3 % and 35.5 % of their body weight for egg production. The knowledge of the reproductive biology reported in the present study is an important tool to define strategies to preserve M. surinamicum in Amazon River mouth.

Geographic variation in plumage coloration of Turquoise Tanager Tangara mexicana (Linnaeus, 1766)

he Turquoise Tanager Tangara mexicana is largely distributed in northern South America, and has been considered a polytypic species comprising four or five subspecies. Our study on plumage coloration of 175 specimens, from localities covering the entire species’ range, revealed the existence of two variable characters: color of underparts and color of lesser upper-wing coverts. Seven morphotypes were found that combine the different states presented by these two characters. Two morphotypes were very distinct, representing two of the most easily diagnosable subspecies (T. m. mexicana, having yellowish white underparts and a contrasting turquoise green humeral patch; and T. m. boliviana, having bright yellow underparts and the blue of lesser upper- wing coverts similar to that of the sides of head, throat, breast and rump). The other morphotypes (including those representing subspecies T. m. media, T. m. vieilloti and T. m. lateralis) are shared by birds with character states that are intermediate between those found in T. m. mexicana and T. m. boliviana, thus representing a polymorphic population ranging widely across central Amazonia, from northern Venezuela and Trinidad to the south of the lower Amazon. This large area may be considered as a hybrid zone of considerable phenotypic instability, more evident especially in the region between the lower Rio Madeira and east of the Tocantins in the Belem area. Based on the General Lineage Species Concept two species could be recognized based on plumage: T. mexicana, restricted to the Guyana center of endemism, and T. boliviana, which is widely distributed in western Amazonia and the eastern foothills of the Andes, an area corresponding to the centers of endemism Napo and Inambari. The taxonomic validity of T. lateralis is once more challenged.

Sistemas regionais, relações interétnicas e movimentos territoriais – os Tapajó e além na história ameríndia

Esse artigo considera o nascimento de um território ameríndio complexo no Baixo Amazonas no final do século XVII. Esse território, identificado pela região dos rios Madeira/Tapajós, pode ser vista como uma zona tribal, fora do contato direto com a sociedade colonial, entretanto conectada a ela. A guerra entre os Tapajó (costa sul, ao redor da foz do rio Tapajós) e os Aruaque (costa norte, ao redor do lago Saracá), que já ocorria durante grande parte do século dezessete, chegou a um ápice no inicio de 1660. Com envolvimento europeu, a guerra acabou gerando consequências para o potencial coletivo de ambas partes, que ficou muito reduzido. Considerando as relações de alianças e combates, esse artigo confronta as transformações internas e externas no Baixo Amazonas, focando na nação tapajó. Será que esses grandes povos se dividiram em etnias diferentes, ou se reagruparam na zona tribal, ou ainda, será que diminuíram e perderam poder?

Systematics and morphology of Potamotrygon orbignyi (Castelnau, 1855) and allied forms (Chondrichthyes: Myliobatiformes: Potamotrygonidae).

The Neotropical freshwater stingray Potamotrygom orbignyi (Castelnau, 1855), and other similar "reticulated" species occurring in northern South American basins, were submitted to a thorough taxonomic analysis based on an extensive external and internal morphological study. The identity of P. orbignyi and the taxonomic status of the related nominal species Potamotrygon dumerilii (Castelnau, 1855), Potamotrygon reticulata (Günther, 1880), and Potamotrygon humerosa Garman, 1913, are defined. Taxonomic and morphological analyses revealed that P. reticulata and P. dumerilii fall within the range of variation found in P. orbignyi and were consequently treated as junior synonyms, corroborating previous works. The extensive variation in coloration observed in P. orbignyi could not be divided into consistent morphotypes; P. orbignyi is therefore a widespread species in the upper, mid and lower Amazonas basin, the Orinoco drainage, and in rivers of Suriname and the Guianas. Additionally, P. humerosa and Potamotrygon marinae Deynat, 2007 were found to present characters that support their validity, and are redescribed based on newly collected material. Potamotrygon humerosa occurs predominantly in the mid and lower Amazonas River and in lower reaches of many of its affluents, whereas P. marinae is known only from French Guiana and Suriname. Characters that proved valuable as diagnostic indicators, either in combination or as derived features, are primarily from coloration, dermal denticles and spines (morphology, development and distribution), meristic features (e.g. numbers of tooth rows, vertebrae and mesopterygial radials), morphometric proportions (e.g. snout length, tail width at base and length), and size at sexual maturity.

The compositional evolution of dissolved and particulate organic matter along the lower Amazon River—Óbidos to the ocean

River systems play a pivotal role in transporting and transforming organic carbon (OC) fixed by terrestrial primary production. However, there is a fundamental gap in our understanding of the connectivity of terrestrial, aquatic, and marine carbon budgets due to a lack of measurements along the lower (i.e. tidally-influenced) reaches of large river systems. For example, all estimates of carbon fluxes from the world's largest river, the Amazon, are based on measurements made at and upstream of Óbidos, roughly 900km from the mouth. Here we examine the evolution of OC concentrations and composition from Óbidos to two discreet channels near the mouth of the Amazon River during five cruises from 2010 to 2012. OC characteristics of the Tapajós River, which enters the Amazon River downstream of Óbidos, and the Tocantins River, which mixes with the Amazon River plume in the Atlantic Ocean, were also assessed.The average concentration of particulate organic carbon (POC) across the two main channels near the mouth was 0.6±0.3mgL−1 during the study period, decreasing from 1.2±1.0mgL−1 at Óbidos. Average dissolved organic carbon (DOC) concentrations, on the other hand, increased from 3.9±0.6mgL−1 at Óbidos to 4.2±0.9mgL−1 across the mouth. The discharge of total OC to the ocean was composed of 89±3% dissolved load, compared to 76±13% at Óbidos. Measurements of bulk OC stable isotopic signatures, chlorophyll a concentrations, and lignin phenol abundance were used to assess unique OC sources along the continuum. For example, the stable isotopic composition of POC and DOC indicated a replacement of highland forest-derived OC with lowland and floodplain-derived OC from Óbidos to the mouth. Likewise, lignin phenol signatures showed an increase in the degradation state of vascular plant-derived OC from Óbidos to the mouth. Results from this study illustrate that the abundance and composition of OC continue to evolve along the lower reaches of large tropical rivers, which has significant implications on estimations of geochemical fluxes to the ocean.

A107 PERCEPTION OF HEALTH AND ACCESSIBILITY IN AMAZONIA: an approach with GIS mapping to making decision on hospital location

Abstract Background Processes of city planning have often supported decision-making methods that involve selection, evaluation and combination of several factors. In addition, nowadays, the accessibility is one important issue for the development of cities. Therefore, factors closely related to the accessibility are very relevant to identify and assess the location of urban facilities, which stresses the interest of evaluating accessibility methods. The main goal of the paper is to present an accessibility analysis applied in a hospital of Santarem, in Brazil, a city located midway between the larger cities of Belem and Manaus. In 2007, The Low Amazonas Regional Public Hospital (LARP Hospital) located in the city of Santarem aiming to decentralize the state health service, taking to the western of Para one reference hospital specialized in medium and high complexity service. Despite the large extension of Low Amazonas region, this area has received unsatisfactory attention in health studies. Methods The paper describes the research instruments, sampling method and data analysis proposed for mapping urban accessibility in health of LARP Hospital in relation to Santarem and other cities in its surrounding, as the main key-destinations. In this sense, the goal of this research was to analyze the accessibility of the LARP Hospital as reference center, what became possible by the georeferencing and interviews with 381 LARP users, considering confidence level of 95% and margin of error of 5%, using a four-part questionnaire: travel pattern; socioeconomics input; service evaluation and main destinations. The model was implemented within a Geographic Information System (GIS) and integrates the individual’s perspective, through the definition of each key destination weight, reflecting their significance for daily activities in health in the region. Results The main options accessibility of the LARP hospital is lowering. Therefore, this justifies the construction of the second high complexity hospital in order to minimize the iniquities of the public health service in the region. Health services in the Lower Amazon is inaccessible for much of the population, mainly by the presence of physical barriers to health, either by distance or by the lack of available means of transport. Conclusions The results of this model application can support city administration decision-making for new investments in order to improve urban quality of live. In addition, the model can simulate and analyze several planning proposal for the city, e.g., expansion of the transport network, the construction of new health services, helping to understand which will be the consequences of those actions.

Community participation in flood mapping in the Amazon through interdisciplinary methods

Community participation is an increasing issue in risk and disaster management. This paper argues that interdisciplinary methods are necessary for mapping flooding areas. On the one hand, hazards can be quantified and mapped through deductive approaches and methods from the natural sciences. On the other hand, hazards can also be described from the population perspective at a local level using social sciences methods. The methods are successfully mixed with a geographical information system environment. In the first case, important inputs include topographic and slope data for geomorphological mapping. In the second case, timeline methodology can indicate temporally the most severe floods, and a participatory map construction gives the population the opportunity to point out the affected areas. These methods were applied in a case study in the lower Amazon River Region in the urban area of the Santarem municipality. High-resolution images and remote sensing were essential tools. Results show that nine neighborhoods have high and moderate susceptibility areas to riverine floods. Another nine neighborhoods are affected by flash floods. Flood mapping is the first step in risk mapping for the sustainability of regional planning.

Market Formalization, Governance, and the Integration of Community Fisheries in the Brazilian Amazon

A major trend in global trade in forest, animal, and agricultural products is the implementation of importation policies and development of private sector standards and certification mechanisms to promote the sustainable management of natural resources in the countries of origin. In many cases, ensuring sustainable origins involves requirements that small-scale rural producers and fishers cannot meet. This article investigates the formalization of community-based floodplain fisheries in the Brazilian Amazon, including (a) the development of federal and state fisheries management policies, (b) the parallel development of community management systems, and (c) the role of these processes in the evolution of fisheries management in the Lower Amazon region. We argue here that market-oriented solutions, such as third-party certification, are insufficient. Government support for and collaboration with producers and industry are essential to creating conditions that enable fishing communities to sustainably manage their fisheries.

How illegal are tropical small-scale fisheries? An estimate for arapaima in the Amazon

Illegal fishing is a problem that affects about 30% of the world fisheries capture, but most studies on the topic to date have focused on large-scale fisheries, leaving tropical small-scale fisheries nearly unstudied even though they possess many features that foster illegal fishing. This article investigated illegal fishing practices for Arapaima spp. in the Lower Amazon Basin, using semi structured interviews and catch and enforcement data. It was found that 77% of the arapaima landings were illegal, with most specimens being caught below the minimum size limit or during the closed season. Also, 86% and 43% of the interviewees stated they have observed declining trends in the landings and size of arapaima, respectively. Finally, spatial and temporal patterns of arapaima landings were not matched by rule enforcement activities. Inadequate enforcement of management rules, combined with geographical dispersion of fishing activities, appear to be a key factors allowing for high levels of illegal fishing, which contribute to the decline of fish populations.

Large- and Medium-Sized Land Mammals of Northeast Marajó Island, Lower Amazon, Brazil

Marajo, located in the lower Amazon, Brazil, is one of the largest river islands in the world. Most of the island is subject to tidal or seasonal flooding. Despite its historical, cultural and geographical importance, Marajo Island remains relatively less investigated in terms of mammal diversity, ecology and community structure than the rest of the Amazon. This scenario has motivated the presentation of this list of land mammals of eastern Marajo Island. Two field surveys were conducted in the course of 7-11 December 2012 and 17-25 October 2013 in Jaranduba, Dunas and Ribanceira Farms, northeast portions of Marajo Island. A total of 23 large and medium-sized land mammal species were recorded in the study area. These farms host a representative mammal community of northeastern Marajo, an area lacking previous faunal studies. Human pressure over centuries has deeply modified the environment in Marajo. Therefore, striking evidence of a long human-populated past in this island is in accordance to many other sites throughout the Amazon plain. The result of a land mammal survey in northeastern Marajo is a clear evidence of past and present human interference in the island. Even though Marajo Island has exalted mammal diversity, it will be much higher if long-term studies are effectively implemented.

A new genus and species of proteocephalidean tapeworm (Cestoda), first parasite found in the driftwood catfish Tocantinsia piresi (Siluriformes: Auchenipteridae) from Brazil.

Frezella gen. n. is proposed to accommodate Frezella vaucheri sp. n. from poorly known auchenipterid fish, Tocantinsia piresi (Miranda Ribeiro), from the Xingú River, one of the principal tributaries of the lower Amazon River in Brazil. The new genus belongs to the Proteocephalinae because of the medullary position of the testes, ovary (yet some follicles penetrate to the cortex on the dorsal side), vitelline follicles and uterus. It differs from other proteocephaline genera in the morphology of the scolex, which includes a metascolex composed of two distinct zones: anterior, strongly wrinkled part posterior to the suckers, and posterior, sparsely folded zone. Frezella can also be differentiated by having the internal longitudinal musculature hypertrophied laterally on both sides, the presence of some ovarian follicles in the cortex on the dorsal side and the presence of additional pair of tiny, thin-walled osmoregulatory canals situated slightly dorsomedian to ventral canals. Frezella vaucheri is the first helminth parasite reported from T. piresi, which occurs in the lower reaches of the Amazon and Tocantins River basins in Brazil.