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Hydrological disconnection in intermittent rivers is known to increase β-diversity by limiting the dispersal of species and decreasing environmental similarity between sites. Knowledge of the mechanisms driving variation within and between local communities helps elucidate the role of environmental and spatial processes responsible for community composition at multiple scales in intermittent rivers. In this study, we investigated the spatial and environmental patterns of zooplankton β-diversity in an intermittent river in a semiarid region in Brazil. We hypothesized that (1) the zooplankton metacommunity is determined primarily by turnover, and (2) the structure of the zooplankton metacommunity is more heavily influenced by environmental than spatial factors. Our samples yielded 46 taxa of rotifers and cladocerans. β-taxonomic diversity was high, with a predominance of turnover compared with nestedness. The partitioning analysis showed that environmental and spatial processes had a significant influence on the distribution of zooplankton species, but the former had the greatest explanatory power. In the redundancy analysis, high values of temperature, oxygen and submersed macrophytes were significantly correlated with species variation. The observed β-diversity values closely reflected the turnover pattern, whereas Cladocera and Rotifera diverged between predictive processes. Our results highlight the importance of adopting appropriate conservation measures for intermittent river networks as a whole.

This study reports on the abundance, biomass and reproductive traits of Oncaea venusta, a common pelagic copepod in tropical oceans, in a coastal area influenced by bottom intrusions of the cold and nutrient-rich South Atlantic Central Water (SACW). In addition to O. venusta abundance and biomass, we estimated egg production and weight-specific fecundity rates by applying the egg-ratio method and incubation experiments, at monthly intervals over 3 years (July 2005–June 2008), to understand potential SACW influences on reproductive patterns. Mean abundance and biomass were low, and no differences were detected with and without SACW intrusions. Mean clutch size (±SD) was 65.1 ± 28.9 eggs female−1 and egg production rates averaged 7.6 ± 12.4 and 9.3 ± 5.2 eggs female−1 day−1 (viability >80%), for the egg-ratio method and incubation experiments, respectively, corresponding to a female weight-specific fecundity from 0.03 ± 0.05 to 0.04 ± 0.06 day−1. Oncaea venusta abundance and biomass were positively correlated with temperature, but no SACW influence on the reproductive rates was recorded. The egg production rate and the female weight-specific fecundity were influenced by the chlorophyll a concentration and the sex ratio. Although egg production and female weight-specific fecundity rates had peak values during intrusion events, no immediate impact on population abundance was observed within the same time interval.

β-Diversity can be driven by different factors, and it is necessary to understand how the characteristics of communities contribute to biodiversity. We investigated composition patterns and taxonomic and functional β-diversity, in addition to determining the possible processes driving the β-diversity of zooplankton in 42 lakes, distributed in two regions with distinct rainfall patterns, a semiarid and a humid region both in the Brazilian Northeast. Environmental heterogeneity was higher in the semiarid region. The species composition was different; however, taxonomic and functional β-diversity did not differ between regions. These data sets showed that although the composition was distinct, the change in species and traits occurred similarly. Taxonomic and functional β-diversity were driven by environmental factors. They showed a predominance of niche assembly and the importance of abiotic variables in the selection of species and traits. In our case, the dispersion limitation did not influence β-diversity. Species are deterministically filtered, and each region imposes a distinct environmental filter that selects them. Due to the limited studies on the partition of functional β-diversity and the uncertainty of ecological patterns for intermittent environments, more scientific research is required that considers this approach for dry regions and over longer time periods.

Harsh and unstable aquatic environments present selective forces that influence environmental heterogeneity, dispersal capacity and specific life history strategies that, in turn, affect species distribution and metacommunity dynamics. To date, relatively few studies have examined the potential of bird-mediated dispersal to connect isolated ephemeral habitats. We used zooplankton from temporary ponds to examine the effects of bird morphological diversity and water availability on microcrustacean diversity in temporary ponds. Three bird feet models were constructed based on small, large and webbed anisodactylous forms in order to simulate bird walking on the pond shore. Bird and zooplankton communities were sampled in two temporary ponds and experimentally simulated zooplankton dispersal by bird on dry sediments. We surveyed in two contrasting seasonal periods. Overall, water availability does affect zooplankton composition, and birds with large feet have higher dispersal capacity. In addition, birds with different feet size and shape carry distinct zooplankton species. During the dry season, sediments hold 100% more species than in the wet season, which indicates that birds have higher potential for dispersing zooplankton in drought conditions. Our findings suggest that bird diversity can maintain zooplankton metacommunities by rescuing dormant organisms from dry ponds and connecting to any available aquatic habitats.

Rotiferos sao organismos geralmente planctonicos utilizados como indicadores da qualidade ambiental em corpos d’agua, por apresentarem a capacidade de responderem rapidamente as variacoes do meio. O objetivo do presente estudo foi investigar se em uma mesma area protegida (Parque Estadual de Dois Irmaos, Pernambuco, Brasil), ambientes aquaticos submetidos a diferentes niveis de exposicao antropica apresentam atributos distintos da comunidade de rotiferos litorâneos. Foram avaliados quatro reservatorios, que foram agrupados em duas categorias de condicoes de exposicao antropica: ( i ) Expostos e ( ii ) Nao Expostos, de acordo com as caracteristicas ambientais do entorno dos reservatorios. Foram registradas 41 especies, das quais 11 ocorreram nos quatro ambientes, e o genero Lecane foi o mais rico em especies (S = 14). A comunidade de rotiferos diferiu entre as duas condicoes de exposicao, com uma maior riqueza e densidade encontrada para o grupo de reservatorios Expostos. A analise de grupos funcionais, atraves do indice de Guild Ratio (GR), resultou em maior dominância de microfagos para o grupo de ambientes Expostos (GR = -0,93), em relacao aos Nao Expostos (GR = -0,69). Mesmo as duas condicoes de exposicao tendo apresentado predominância de rotiferos de habito alimentar microfago, que sao indicadores de degradacao do ecossistema aquatico, constatou-se uma menor representacao desse grupo funcional nos reservatorios Nao Expostos. Nossos resultados indicam que os rotiferos planctonicos litorâneos apresentam respostas confiaveis para a avaliacao ambiental de reservatorios rasos, e que condicoes distintas de manejo podem influenciar o status ambiental de ecossistemas aquaticos de uma mesma area protegida. ROTIFERA FROM RESERVOIRS UNDER DIFFERENT ENVIRONMENTAL CONDITIONS IN A PROTECTED FRAGMENT OF ATLANTIC RAIN FOREST Rotifers are generally planktonic organisms used as indicators of environmental quality in water bodies because they can quickly respond to environmental variations. The present research aimed to investigate whether in the same protected area (Dois Irmaos State Park, state of Pernambuco, Brazil) aquatic environments submitted to different levels of anthropic exposure present different attributes of the community of littoral rotifers. Four reservoirs were evaluated and grouped into two categories according to antropic exposure conditions: ( i ) Exposed and ( ii ) Not Exposed, according to the environmental characteristics of the surroundings of the reservoirs. Forty-one species were recorded, of which 11 occurred in the four reservoirs, and the genus Lecane was the richest in species (S = 14). The rotifer community differed between both exposure conditions, with a greater richness and density found for the group of Exposed reservoirs. The analysis of functional groups, through the Guild Ratio index (GR), resulted in a higher dominance of microphages for the Exposed group (GR = -0.93), than for the Not Exposed group (GR = -0.69). Even though both exposure conditions were dominated by microphage rotifers, which are indicators of aquatic ecosystem degradation, a lower representation of this functional group was observed in the Not Exposed group of reservoirs. Our results indicate that coastal planktonic rotifers present reliable answers for the environmental evaluation of shallow reservoirs, and that different management conditions can influence the environmental status of aquatic ecosystems of the same protected area.

Phytotelmata are habitats that house several species. Oftentimes invertebrate species need to disperse themselves sometimes carried by other animals, an interaction called phoresy. Phoresy can be influenced by different factors, therefore, we aim to investigate which factors influence the phoretic potential between anurans and invertebrates from bromeliads in semideciduous Atlantic Forest, as well as whether there is specificity of invertebrates with any anuran species. We tested if (a) phoresy is more common under conditions with higher rainfall; (b) there are some species of anurans that influence the phoresy of invertebrates more than others; (c) size is an important factor to phoresy. The study was developed during six campaigns in two sites containing the bromeliad Aechmea leptantha. In each campaign, water of bromeliads was collected and all anurans found in bromeliads were processed by washing the skin to collect adhered invertebrates. We recorded the prevalence, average intensity and average abundance of invertebrates between anuran species. We verified the similarity of invertebrates between anuran taxa and we tested the hypothesis of independence between them. In order to identify which factors affect phoresy, we performed a GAMLSS analysis. Invertebrates were present on 54.4% of anurans distributed in five species: Dendropsophus decipiens, Scinax pachycrus, S. x-signatus, S. auratus and Pristimantis ramagii. The estimated densities for prevalence, average intensity and average abundance of invertebrates showed distinct shapes among the anuran species, of which not all participate in the same way in invertebrate transport. The mean phoretic potential showed a significant relationship with anuran length and rainfall.

The Brazilian oil spill, from August 2019 to January 2020, was considered the most extensive accident in tropical oceans. We estimated the concentration of oil droplets that may be available for ingestion by microzooplankton. The collection was carried out in three areas: estuarine plume, bay and reef (Tamandare, Pernambuco coast). We highlight the contribution of coral larvae in the reef region, surpassing the copepods, evidencing a spawning event. Oil droplets were recorded in all the sampled areas, with a high numerical abundance in the plume. Traces of oil ingestion by Brachyura zoea and Calanoida, Paracalanidae and Oithonidae copepods were observed, suggesting that these groups might have an important role in the degradation and final destination of oil dispersed after spills. The vulnerability of the larval phases of crabs and reef-building corals has been hypothesized, suggesting that the negative effects of oil on zooplankton can affect the recruitment of benthic invertebrates.

The study was conducted to assess the community structure of planktonic rotifers and their relation to the environmental impact of Nile tilapia, Oreochromis niloticus (Linaeus, 1758), aquaculture activities (ponds and net-tanks), associated with a Neotropical semiarid reservoir in Brazil. Our hypothesis was that the ecological attributes of the rotifer community were different when considering the influence of fish aquaculture activities. We identified 28 species, with 10 species from the Brachionidae family. The average density and diversity index of rotifers were higher in reservoir stations, with mean values in the ponds approximately 50% lower than those of the reservoir. The microphagous species dominated during all the time, while the raptorial species were accidental in all studied environments. The ponds were represented by four significant indicator species: Brachionus caudatus, B. leydigi, Dicranophoroides caudatus and Testudinella patina and the reservoir by three: B. falcatus, B. havanaensis and Conochilus dossuarius. In general, nine species were significantly associated with some categories of environmental conditions, such as high or low turbidity and low values of conductivity and TDS. Four of the five best bioindicator species belonged to the microphagous genus Brachionus. B. havanaensis indicated five environmental conditions (IndVal > 93.1%), and it appeared to be a key species in this Neotropical semiarid reservoir influenced by aquaculture activities. The dominance of microphagous rotifers suggests a functional redundancy of species in the studied environments. We found that these systems and their management affected the planktonic rotifer community in this region of Brazil by increasing the species richness.

Although it has been proven that non-predatory mortality accounts for a large proportion of copepod mortality, there is still a lack of knowledge of the temporal and spatial patterns and influence of environmental variables on non-predatory mortality, especially in tropical areas where reefs are influenced by estuarine plumes. This study evaluated the percentage of carcasses and the non-predatory mortality rates for planktonic nauplii and copepodites in a bay with the presence of reefs under the influence of an estuarine plume, in the Atlantic tropical region. The average percentage of carcasses was less than 13% for both nauplii and copepodites, and was close to the minimum for other marine environments. However, there was a variation according to the different families and life stages of planktonic copepods. Nauplii had the highest mortality rate, with a mean rate of 0.04 ± 0.02 day−1 (maximum, 0.11 day−1), while the copepodites had a mean of 0.03 ± 0.01 day−1 (maximum of 0.06 day−1). Non-predatory mortality was higher in the rainy season, and differed between the nearby studied areas (bay, plume and reefs). Considering the three areas separately, only the estuarine plume showed higher percentages of carcass and non-predatory mortality rates of nauplii and copepodites. The increase in mortality rates for some copepod families was influenced by high salinity and low values of chlorophyll-a, dissolved oxygen and pH. These results demonstrate that the non-predatory mortality of copepods varies in a complex mosaic of interconnected ecosystems, and that the relationships between environmental variables with some groups may indicate susceptibility of different stages and families to death due to specific environmental conditions.

The present study aimed to determine zooplankton diversity and composition through a laboratory simulation of dispersal by morphologically different birds’ feet (large, small and webbed anisodactylous feet) and by comparing them between different water accumulation phases. We hypothesized that large anisodactylous birds, because of their larger size, can disperse a higher number of species. A laboratory experiment with zooplankton dispersal simulation by birds’ feet was carried out, using dry sediments collected at different past phases of water accumulation in a temporary pond, which represent the flood (upper egg bank) and drought (lower egg bank), intending to evaluate differences in species richness between these phases. The lower egg bank showed higher species richness (42 species) while the samples from upper egg banks presented almost the same number of species (35 or 36 at each one). The number of eggs carried on each footprint model (treatment) was different, and it was higher for large anisodactyl feet with 46 species, supporting the hypothesis of the study. Furthermore, the species compositions carried by footprint models were different from one other. In addition, some species were specific from each footprint model. We conclude that birds can disperse a large number of dormant zooplankton, acting in the dissemination of local species.

We provide a baseline assessment of the density and types of microplastics in the western equatorial Atlantic. The highest microplastics density was found in coastal stations near urbanized sites, large tropical estuaries, and fishing grounds. With regard to microplastics composition, most of the identified particles were fibers/filaments, styrofoam, hard and soft plastic, paint, and glass/acrylic. Fibers/filaments were the most abundant (~80%) and occurred at all stations, in both types of mesh nets. Hard plastic particles were frequent (78%) only in the 120 μm mesh net. The mean density recorded in the 120 μm mesh net was about seven times greater than that in the 300 μm mesh net, suggesting that the larger mesh size net did not lead to an accurate description of microplastics density in the pelagic environment or the degree of risk to which organisms are exposed.

In the semi-arid region of Brazil, artificial reservoirs are ecosystems of extremely important ecological and social. Due to pressures caused by long periods of pluviometric irregularity, the reservoirs Cachoeira I and Barra, located in the interior of Pernambuco, have been subject to very significant changes, marked mainly by the reduction of stored water volume, seasonal changes in the abiotic parameters, reduction of riparian vegetation and absence of macrophytes. All these changes were observed in this study through the use of an auxiliary monitoring tool, a rapid assessment protocol adapted for lentic ecosystems of semiarid, capable of detecting numerous types of environmental changes, assisting in monitoring these springs.

In early September 2019, dense crude oil began to wash the beaches of Brazil's tropical coast. Four months after the first report, the oil has already been found along >3000 km of the Brazilian coastline on >980 beaches and was recently observed along the Amazon coast, making this oil spill the most extensive and severe environmental disaster ever recorded in Brazilian history, in the South Atlantic basin, and in tropical coastal regions worldwide. Four features of this oil-spill disaster make it unique: 1) the characteristics of the oil spill; 2) the characteristics of the affected region in tropical Brazil; 3) the significant number of protected areas (>55) and tropical ecosystems affected by the oil; and 4) the absence of measures and/or flaws in the measures taken by the federal government to address this environmental and social emergency. The affected species and poor human communities in Brazil should receive focused attention in the coming decades owing to the long-term impacts of the oil contamination. Environmental monitoring and response measures must be implemented to minimize the ecological, economic, and social effects of the spill. Biodiversity and climate regulation losses considering blue carbon environments should drive discussions regarding mining accidents and global consequences related to pre-salt oil exploitation, new spill events, and their global impacts. These measures are particularly relevant in areas with high tropical biodiversity and high social inequality, as in the present case, which represents one of the worst-case scenarios of an environmental and governmental disaster.

In the present work, spatial and seasonal fluctuations of the abundance and diversity of mesozooplankton are presented, with special attention being given to copepod assemblages from coastal area of the Fernando de Noronha Archipelago (FNA) (3°50'24''S and 32°24'48''W). Sampling was carried out during the dry and rainy seasons of two consecutive years (July and December 2013) and (June and November 2014). A total of 37 mesozooplankton taxa were recorded, being the copepods the most diversified group (15 taxa). The Subclass Copepoda dominated in both periods sampled, comprising 53% and 86% of the total abundance in the dry and rainy season respectively. The species considered abundant were: Calanopia americana, Undinula vulgaris, Oithona plumifera and Corycaeus speciosus. The rainy season favored a significant increase in the abundance of mesozooplankton and copepods. However, a low value of the Shannon-Wiener diversity index was observed in this same seasonal period. This was explained by the dominance of the species C. americana and U. vulgaris in the studied area. Spatial differences have not been verified. The copepod assemblages was composed mostly by species considered as predator-carnivours of greater importance on the pelagic trophic web, indicators of oligotrophic conditions and components of a major portion of fish food items. Thus, we suggest that a spatially homogeneous mesozooplankton community characterizes the coastal area of Fernando de Noronha Archipelago with variations related mainly to the seasonal factor. Resumo Neste presente trabalho, são apresentadas as flutuações espacial e sazonal da abundância e diversidade do mesozooplâncton, com especial atenção para assembleia de copépodes da área costeira do Arquipélago de Fernando de Noronha (AFN) (3°50'24''S and 32°24'48''W). A amostragem foi realizada durante as estações seca e chuvosa de dois anos consecutivos (julho e dezembro de 2013) e (junho e novembro de 2014). Um total de 37 taxa do mesozooplâncton foram registrados, sendo os copépodes o grupo mais diversificado (15 taxa). A Subclasse Copepoda dominou em ambos os períodos amostrados, com valores de abundância relativa equivalentes a 53% e 86%, respectivamente, nas estações seca e chuvosa. As espécies consideradas abundantes foram: Calanopia americana, Undinula vulgaris, Oithona plumifera e Corycaeus speciosus. A estação chuvosa favoreceu um aumento significativo na abundância do mesozooplâncton e copépodes. No entanto, um baixo valor do índice de diversidade de Shannon-Wiener foi observado para este mesmo período sazonal. Isso foi explicado pelo domínio das espécies C. americana e U. vulgaris na área estudada. Diferença espacial não foi verificada. A assembleia de copépodes apresentou um maior número de espécies consideradas carnívoro-predador de grande importância na teia trófica pelágica, indicadoras de condições oligotróficas e componente de grande porção dos itens alimentares dos peixes. Assim, sugerimos que a área costeira do Arquipélago de Fernando de Noronha é caracterizada por uma comunidade do mesozooplâncton espacialmente homogênea, onde as mudanças observadas estão principalmente relacionadas ao fator sazonal.

Este trabalho objetivou inventariar as espécies de anfíbios e répteis no sítio Olho d’Água, Santa Cruz da Baixa Verde, Pernambuco, destacando sua ocupação nos diferentes hábitats e microhabitats, bem como seu status de conservação. A coleta dos dados foi realizada em agosto de 2010 a junho de 2011, através de buscas ativas e passivas, utilizando armadilhas de interceptação e queda - modelo padrão pit fall traps, nos períodos diurnos e noturnos nos sítios refúgio, alimentação e procriação desses táxons. Foram registradas 19 espécies de anfíbios distribuídas em seis famílias, todas pertencentes à ordem Anura: Bufonidae (2), Hylidae (5), Leiuperidae (1), Leptodactylidae (8), Pipidae (1) e Cycloramphidae (2) e 15 espécies de répteis distribuídos entre 10 famílias, essas pertencentes à Tropiduridae (2), Gekkonidae (1), Teiidae (2), Iguanidae (1), Gymnophthalmidae (1), Leiosauridae (1), Sphaerodactylidae (1), Phylloctylidae (1), Dipsadidae (4) e Viperidae (1). A lista apresentada no presente trabalho é bastante representativa do ponto de vista regional e principalmente no que se refere ao semiárido brasileiro, destacando elementos de áreas mésicas e xéricas. A comunidade da herpetofauna para a localidade estudada é composta por espécies típicas de Caatinga com alguns elementos de área úmida.

This paper aims to compare alpha and beta diversities of planktonic microcrustaceans from three reservoirs located nearby in a tropical semiarid basin. Our hypothesis was that alpha and beta diversities of the community are different, although the ecosystems are located close to each other. We carried out two sampling campaigns: dry and rainy seasons. The sampling of microcrustaceans and environmental variables (dissolved oxygen, chlorophyll a and nutrient) was performed at twelve stations and were distributed throughout the three zones (river, transition, and lacustrine), using a plankton net (45 µm). The reservoirs showed different uses and types of nitrogen predominance: Cachoeira (supply/nitrate), Borborema (sewage/ammonia) and Saco (aquaculture/ammonia). Seventeen species were recorded whose richness was assessed as particularly specific to each one of the studied reservoirs. Seasonally, both reservoirs with high anthropogenic alteration showed greater richness in the dry season. The three reservoirs located in a same basin showed different richness and composition, but the diversity did not differ between the zones of the reservoirs. Although communities are close to each other, their composition and richness were found to be distinct for each reservoir. This may be in response to the peculiar particularities, such as nitrogen sources and the different uses.

Assessing zooplankton biodiversity is essential to support freshwater management/conservation programs. Here, we investigated the zooplankton community structure from 180 shallow lakes in northeastern Brazil and analyzed them according to biome (Atlantic Forest or Caatinga), the origin of ecosystems (natural or man-made lakes), and habitat type (pelagic or littoral). Additionally, we provided an updated list of zooplankton species. We registered 227 species (137 Rotifera, 65 Cladocera, 25 Copepoda). The most common species of each major group among all lakes were the cladoceranCeriodaphina cornuta, the rotifersBrachionus havanaensisandLecane bulla, and the copepodTermocyclops decipiens. Species related to aquatic vegetation, as the Lecanidae rotifers and phytophilous cladocerans, were more frequent along Atlantic Forest biome and natural lakes. On the other hand, species that are bioindicators of eutrophic waters were more common at the Caatinga biome and man-made lakes. Atlantic Forest and Caatinga biomes had similar species richness, but different community compositions for all zooplankton groups, reinforcing the Caatinga significance for the Brazilian aquatic biodiversity. The type of habitat was the most important factor structuring species richness, with higher richness in the littoral region when compared to the pelagic. A result of many unique species of Cladocera and Rotifera associated with the aquatic vegetation were observed. The findings demonstrated that conservation/management plans cannot generalize zooplankton species distribution across different biomes, origins and even within a single lake, between the pelagic and littoral zones.

Zooplankton biomass (as wet weight) was studied around marine protected islands in the tropical Atlantic Ocean. The study was based on 96 zooplankton samples collected during a 3-year period; specifically, 2010 was considered a year of thermal stress, and 2012 and 2014 were considered years without thermal stress. The analysis showed that zooplankton biomass varied significantly among protected areas, where the smallest and most isolated archipelago among the tropical islands, Saint Peter and Saint Paul Archipelago (SPSP), had approximately twice the biomass of Fernando de Noronha Archipelago (FN) and three times that of Rocas Atoll (RA). The position of SPSP near the equatorial divergence zone, the seasonal occurrences of phytoplankton blooms east of the Equator, the contribution of the productive waters that SPSP receives from the African coast under the influence of the South Equatorial Current (SEC) system and the local upwelling effect induced by the presence of the island were considered to be the factors responsible for the high pelagic productivity in this remote archipelago. Differences between day and night were also recorded. The high nocturnal biomass was considered an effect of the capture of larger-sized animals, which are considered to be strong migrators. The lowest zooplankton biomass was recorded in 2010 and was considered an apparent effect of the high sea surface temperature observed in that year. However, the interaction between spatial and interannual factors showed that, in FN and SPSP, the zooplankton biomass was lower in the year under thermal stress (2010). In contrast, RA presented a higher biomass value in this period. We suggest that this increase in zooplankton biomass is the result of the contribution of autochthonous sources (e.g., as a consequence of local physical events, such as current wakes, recorded during this period at RA and responsible for the increase in local planktonic productivity) and allochthonous sources (e.g., organisms supplied by FN via the zonal current).

We investigated the reproductive biology of the planktonic harpacticoid copepod Euterpina acutifrons, including morphometric data, egg production rates (EPR) and viability, and weight-specific egg production. Experiments were carried out during 1 year in an inner-shelf area off Ubatuba (SE Brazil), a site seasonally influenced by bottom intrusions of the relatively cold and nutrient-rich South Atlantic Central Water (SACW). We hypothesized that E. acutifrons attain higher reproductive rates when SACW penetrates in this region. Live females were incubated individually in cell culture plates during two periods of 24 h each, under controlled temperature and light conditions. Euterpina acutifrons carried on average 16.9 ± 6.9 eggs·sac−1, ranging between 10.8 ± 5.7 and 30.8 ± 7.4 eggs·sac−1. Estimated EPRs ranged from 6.3 ± 3.4 to 13.6 ± 4.2 eggs·female−1·day−1, with mean weight-specific egg production rates of 0.06 ± 0.04 and 0.17 ± 0.08 per day. Euterpina acutifrons was not directly influenced by SACW intrusions, but body length and clutch size were positively related to temperature and chlorophyll content. Egg hatching time was clearly dependent on water temperature, as a 2 °C increase resulted in a decrease of 15 h in egg hatching time. This shows that even a small variation in temperature may considerably affect E. acutifrons population dynamics. Reproductive traits of this pelagic harpacticoid seem, therefore, to be controlled by the trade-offs between increased food supply and the metabolic demands at low temperatures associated with SACW bottom intrusions toward this coastal area.

Composition changes of decapod larvae in a neotropical estuarine inlet (Catuama inlet, northeast Brazilian coast) were studied in a complete tidal cycle in August 2001. Sampling was performed at three stations at two or three depth levels that were located along a transect across the inlet. The collections were performed in 3 h intervals under a neap tide regime. Samples were taken with a pump and the water was filtered through 300 μm plankton net. 27 planktonic decapod taxa were identified, which included the first larval stages of the coastal and oceanic shrimps Lucifer faxoni and Acetes americanus, besides larvae of the estuarine and coastal decapods Pinnixa spp., Uca spp., Petrolisthes armatus , Upogebia spp. and Alpheidae, which were the most frequent taxa. All of the planktonic larval stages were observed for most of the decapods, suggesting that the probable exportation from the estuary is to the inner adjacent shelf area, instead of the outer oceanic area. Keywords: decapod larvae, meroplankton, tidal changes, neotropical estuary, northeastern Brazil.

The aim of this study was to evaluate the phytoplankton–zooplankton interaction, using phytoplankton morphology-based functional groups, in two reservoirs that have different trophic state indices (TSIs). We hypothesised that the herbivorous relationships of zooplankton with the phytoplankton community would differ between reservoirs with different TSIs. In order to test this hypothesis, field collections to study the phytoplankton, zooplankton and abiotic variables were undertaken between July 2016 and April 2017 from the subsurface layer and in situ experiments were conducted using biomanipulation of the micro- and mesozooplankton. In situ experiments consisted of 18 microcosms in 5-L transparent plastic bottles (in triplicate). The mesotrophic reservoir showed predominance of chlorophytes (Group IV) and mesozooplankton during the study period. In the presence of zooplankton, all phytoplankton groups showed negative growth rates and higher ingestion values, mainly Group IV. In the supereutrophic reservoir, ingestion rates showed that micro- and mesozooplankton reduced the biomass of colonial (Group VII) and filamentous (Group III) cyanobacteria respectively. The findings of the present study reveal that Copepoda Calanoida, as well as small cladocerans, may be the most suitable zooplankton groups for biomass biomanipulation of different morphofunctional phytoplankton groups in mesotrophic reservoirs, and for the control of cyanobacteria in supereutrophic reservoirs.

The objective of this study was to quantify the zooplankton biomass transport between the Santa Cruz Channel (SCC) at Catuama north inlet and the adjacent shelf located in Itamaracá estuarine ecosystem, Pernambuco State, Northeastern Brazil. Sampling was carried out in August 2001 at spring and neap tides at three stations every 3-hour interval. Collections were made in three depths with a plankton pump coupled to a 300 µm mesh size net. Current data were obtained with an ADCP (Acoustic Doppler Current Profiler). In laboratory, samples were filtered for wet weigh determination. High biomass variation was recorded, with highest values at nocturnal flood and ebb during spring tide. The average instantaneous biomass transport was 139.48 ± 72.58 mg.m-2s-1, during spring tide and 36.63 ± 27.66 mg.m-2s-1, during neap tide. No significant difference was registered between importation and exportation flows (p > 0.05), showing that the estuary both exports and imports high biomass during the rainy season. It can be concluded that the outwelling at SCC is high, however, differently from other places, importation is also high, probably due to the presence of reefs and patches of seagrass (Halodule wrightii) toward the shelf that create a distinct productive environment.Este trabalho objetivou quantificar o transporte da biomassa zooplanctônica entre o Canal de Santa Cruz (CSC), na Barra de Catuama, e a plataforma adjacente no sistema estuarino de Itamaracá, Nordeste do Brasil. As coletas foram realizadas em agosto/2001 durante as marés de sizígia e quadratura em três estações a cada 3 horas. As coletas foram em três profundidades com auxílio de bomba acoplada à rede de plâncton com 300 µm de abertura de malha. Dados de corrente foram obtidos com perfilador acústico de corrente (ADCP). Em laboratório, as amostras foram pesadas para obter o peso úmido. Foram registradas grandes variações na biomassa com valores mais altos nas marés enchente e vazante noturna durante maré de sizígia. O transporte instantâneo médio da biomassa foi de 139,48 ± 72,58 mg.m-2.s-1, durante a sizígia, e de 36,63 ± 27,66 mg.m-2.s-1, durante a quadratura. Os fluxos de importação e exportação não apresentaram diferenças significativas (p > 0,05), evidenciando exportação e importação de grande quantidade de biomassa no período chuvoso. Conclui-se que a exportação do CSC é alta, porém diferentemente de outros locais, a importação também é alta, possivelmente pela presença de recifes e prados de fanerógamas (Halodule wrightii) em direção à plataforma, criando um ambiente produtivo distinto.

The aim of this study is to describe a new species of the costata-group from Brazil. Alona margipluma sp. nov. shares morphological traits with A. costata Sars, 1862, A. natalensis Sinev, 2008, and A. cheni Sinev, 1999, but differs from them in: (i) thin setulae between the marginal setae on the valves, (ii) setae 4-5 on the exopodite of limb III long and different in length, (iii) bottle-shaped sensillum on the basal endite of limb IV. For identification of Alona margipluma sp. nov. it is necessary to check carefully the main head pores and postabdomen characters since the former superficially resemble A. iheringula, A. setigera and Alona guttata.

This communication is the first report of the occurrence of the order Mormonilloida (Mormonilla phasma) in the tropical Southwestern Atlantic Ocean. Female individuals were found in surface waters from the shelf break state of Rio Grande do Norte (Northeastern Brazil) and between depths of 60 and 100 m in the epipelagic layer around the St. Peter and St. Paul Archipelago (equatorial Atlantic). This finding extends the vertical limits for this species. Esta nota é o primeiro registro da ocorrência de Mormonilla phasma(Copepoda) no Sudoeste do Oceano Atlântico Tropical. Indivíduos fêmeas foram encontrados em águas superficiais na quebra da plataforma do estado do Rio Grande do Norte (Nordeste do Brasil) e entre 60 e 100 m de profundidade, na camada epipelágica ao largo do Arquipélago de São Pedro e São Paulo (Atlântico Equatorial). Este achado estende o limite vertical da espécie.

The Saint Peter and Saint Paul Archipelago (SPSPA) are located close to the Equator in the Atlantic Ocean. The aim of this study was to assess the spatial variations in the copepod community abundance, and the biomass and production patterns of the three most abundant calanoid species in the SPSPA. Plankton samples were collected with a 300 µm mesh size net along four transects (north, east, south and west of the SPSPA), with four stations plotted in each transect. All transects exhibited a tendency toward a decrease in copepod density with increasing distance from the SPSPA, statistically proved in the North. Density varied from 3.33 to 182.18 ind.m−3, and differences were also found between the first perimeter (first circular distance band) and the others. The total biomass varied from 15.25 to 524.50 10−3 mg C m−3 and production from 1.19 to 22.04 10−3 mg C m−3d−1. The biomass and production of Undinula vulgaris (Dana, 1849), Acrocalanus longicornis Giesbrecht, 1888 and Calocalanus pavo (Dana, 1849) showed differences between some transects. A trend of declining biodiversity and production with increasing distance from archipelago was observed, suggesting that even small features like the SPSPA can affect the copepod community in tropical oligotrophic oceanic areas. O arquipélago de São Pedro e São Paulo (ASPSP) está localizado próximo ao Equador, no oceano Atlântico. O objetivo deste estudo foi avaliar variações espaciais nos padrões de abundância da comunidade de Copepoda, e da biomassa e produção das três espécies de Calanoida mais abundantes no ASPSP. Amostras de plâncton foram coletadas com rede com 300 µm de abertura de malha, ao longo de quatro transectos (norte, leste, sul e oeste do ASPSP), com quatro estações cada. Todos os transectos exibiram uma tendência de redução da densidade dos Copepoda com o aumento da distância do ASPSP, provado estatisticamente para o Norte. A densidade variou de 3,33 a 182,18 ind.m−3, e diferenças também foram observadas entre o primeiro perímetro (primeira faixa de distância circular) e os demais. A biomassa total variou de 15,25 a 524,50 10−3 mg C m−3 e a produção de 1,19 a 22,04 mg C m−3d−1. A biomassa e produção de Undinula vulgaris (Dana, 1849), Acrocalanus longicornis Giesbrecht, 1888 e Calocalanus pavo (Dana, 1849) apresentaram diferenças entre alguns transectos. Uma tendência de declínio da biodiversidade e produção com o aumento da distância do arquipélago foi observada, sugerindo que pequenas feições como o ASPSP podem afetar a comunidade em áreas oceânicas oligotróficas tropicais.

A prática da educação ambiental é ainda incipiente, apesar de ser um importante instrumento mobilizador dos vários segmentos da sociedade. Este trabalho apresenta uma síntese das experiências realizadas nos manguezais do Canal de Santa Cruz, Pernambuco - Brasil, objetivando a formação de competências locais para a avaliação e monitoramento das condições ambientais de ecossistemas costeiros que constituem a base de seu sustento tradicional. Foram oferecidas oficinas de transferência de conhecimento aos filhos de pescadores provenientes de comunidades carentes próximas aos manguezais da região, possibilitando um contato direto dos grupos locais com o conhecimento formal transmitido. O objetivo geral destes programas foi formar guias ambientais para multiplicação dos conhecimentos. Destacaram-se entre as atividades realizadas: confecção de cartilhas didáticas; produção de caixas zoológicas com ênfase às espécies de importância econômica para a região; criação de histórias em quadrinhos com temas trabalhados em sala de aula; visitas ao campo e coleta didática de organismos. Secundariamente, realizou-se a introdução de viveiros de mudas de mangue-vermelho Rhizophora mangle L. em habitações localizadas em áreas de manguezal. Aliando teoria e prática, permitiu-se que os alunos desenvolvessem uma melhor compreensão da dinâmica do ecossistema manguezal, seu papel ecológico e a importância de sua conservação, a partir de seus conhecimentos prévios. Ao término das atividades, observamos que os jovens assimilaram grande parte dos conhecimentos transmitidos, despertando em cada um a preocupação pela conservação e preservação dos recursos dos manguezais da região. Palavras-chave: Comunidades tradicionais, educação ambiental, manguezal, Nordeste do Brasil.

We investigated the influence of nutrient-rich oceanic waters in comparison to the estuarine outflow from Santos Bay (SE Brazil) on copepod abundance and production on the adjacent inner shelf. Zooplankton samples were collected with a Multinet in spring 2005 and in summer 2006. Copepod biomass was derived from length―weight regressions, and growth rates were estimated from empirical models. Altogether, 58 copepod taxa were identified. The highest abundances were due to small-sized organisms including nauplii, oncaeids and copepodids of paracalanids and clausocalanids. Biomass and secondary production mirrored copepod abundance, with Temora copepodids accompanying the above-mentioned taxa as major contributors. The contribution of naupliar biomass and production was low (2.2 and 3.8% of the total, respectively). The influence of the Santos Bay outflow was observed only in spring when Coastal Water (CW) dominated at the study site; whereas in summer the inner shelf was occupied by CW in the suface layer and the oceanic South Atlantic Central Water (SACW) in the bottom layer. The SACW intrusion had more of an influence for the increase in copepod production than the Santos Bay plume. The distribution and dynamics of the oceanic water masses seemed to be the most important influence on copepod diversity and production at this subtropical site.

The objective of this study was to quantify and to model zooplankton transport with emphasis on decapod crustacean larvae. Sampling was carried out at three depths with a plankton pump coupled to a 300-/¿m mesh. Current data were obtained with an ADCP. Our data showed the existence of vertically and horizontally heterogeneous current and transport fields. We identified 27 groups of Decapoda (larvae of Sergestidae, Porcellanidae, Upogebiidae, Cari dea, Brachyura). Most of the species and larval phases showed characteristic vertical migration patterns, in phase with the diurnal tidal cycles, thus enhancing retention or export from the estuary.

Este trabalho apresenta uma avaliação do estado da arte da biodiversidade de rotíferos planctônicos de alguns ecossistemas aquáticos continentais para Pernambuco (Brasil). Um levantamento bibliográfico foi realizado e a maior parte das pesquisas enfocou aspectos sazonais e estado trófico dos ecossistemas. Pelo menos 19 locais foram estudados no tocante aos rotíferos. O Sertão é a região mais estudada. Nesta pesquisa foram registradas 64 espécies de rotíferos planctônicos, distribuídas em 18 famílias e 29 gêneros. As espécies mais freqüentes nos locais estudados foram Keratella tropica e Brachionus falcatus, mostrando que a maior parte dos estudos foi realizada na zona limnética. Os resultados sugerem ainda a necessidade de mais pesquisas sobre a biodiversidade deste grupo em locais localizados na Zona da Mata e no Agreste, bem como em ecossistemas lóticos e nas zonas litorâneas dos locais, tendo em vista a carência de informações. The state of the art in planktonic rotifers biodiversity from some freshwater ecosystems was elaborated for the state of Pernambuco (Brazil). A bibliographic survey was done and most studies focused seasonal aspects and trophic state of the ecosystems. At least 19 continental aquatic environments related to rotifer researches have been studied. The Sertão area was the most studied. The present survey registered 64 species of planktonic rotifers, distributed in 18 families and 29 genera. The most frequent species were Keratella tropica and Brachionus falcatus, showing that most studies were done in the limnetic zone. The results showed the need for more research on the biodiversity of this group in ecosystems located in Zona da Mata and Agreste areas, as well as in lotic systems and in the littoral zones, in view of the lack of information.