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Integrated models (IMs) for stock assessment are simultaneously fit to diverse data sets to estimate parameters related to biological and fishery processes. Model misspecification may appear as contradictory signals in the data about these processes and may bias the estimate of quantities of interest. Auxiliary diagnostic analyses may be used to detect model misspecification and highlight potential solutions, but no set of good practices on what to use exist yet. In this study, we illustrate how to use auxiliary diagnostic analyses not only to identify model misspecification, but also to understand what data components provided information about abundance. The diagnostic tools included likelihood component profiles on the scaling parameter, age-structured production models, catch-curve analyses, and two novel analyses: empirical selectivity and monthly depletion models. While the likelihood profile indicated model misspecification, subsequent analyses were required to indicate the causes as unmodelled changes in selectivity and spatial structure of the population. The consistency between the catch-curve models, the monthly depletion models and the IM information on abundance comes from a strong signal shared by several purse-seine fisheries data sets: the length composition data informs absolute abundance while the indices of abundance constrain the trend in relative abundance.

Reference points are used to determine whether overfishing is occurring, a stock is overfished, or the abundance of the stock is approaching an undesirable level. Reference points are often classified as limit reference points, which indicate an undesirable state, or target reference points, which specify a desirable one. Limit reference points frequently indicate a state for which the reproductive potential of the stock is impacted, and are thus based on spawning output. Spawning output is also used in the stock-recruitment curve, which is a key component of stock-assessment models. We investigated the effect on stock assessment results of metrics of spawning output that are used either in the stock-recruitment relationship or to evaluate reference points. We use yellowfin tuna (Thunnus albacares) in the eastern Pacific Ocean as an example. The metrics biomass of mature females and fecundity attribute higher reproductive potential to the older ages, while numbers of mature females and summary biomass attribute more to the younger ages. Both the stock assessment results and the evaluation of reference points are sensitive to the metric used. The most optimistic perceptions of stock status are obtained when using numbers of mature females, female summary biomass or summary biomass to evaluate the reference points. The choice of metric may be as important as the uncertainty about steepness of the stock-recruitment curve. Given the difficulty in determining the appropriate measure of spawning output and the fact that populations fluctuate naturally, it is recommended that fishing mortality-based reference points are given more consideration for management advice aiming to maintain stocks at desirable states (target reference points) and that harvest control rules based on both types of reference points be compared for their relative effectiveness in avoiding recruitment overfishing and achieving other fisheries objectives using Management Strategy Evaluation.

Spatiotemporal models of catch rate data are used in fisheries science to understand the spatiotemporal dynamics of a fishery and, more importantly, to produce a standardized index of relative abundance for stock assessment models. Here, we apply a spatiotemporal delta-generalized linear mixed model to catch rate data collected from the dolphin-associated purse-seine fishery for yellowfin tuna (Thunnus albacares) in the eastern Pacific Ocean during 1975–2016. Results show that the density of yellowfin tuna had both pronounced spatial variation across the eastern Pacific Ocean and spatiotemporal variation at time scales from quarterly to decadal. In comparison to the index of relative abundance standardized via the spatiotemporal approach, that computed via the nominal approach, which is currently used in the stock assessment, under- and over-estimates initial and terminal abundances, respectively, by as much as 50% or more. The standardized index represents an improvement over the nominal index because the spatiotemporal approach imputes population density in unfished areas to obtain an area-weighted index and accounts for vessel-specific differences in fishing efficiency. The importance of area-weighting for index standardization is highlighted by the fact that ignoring it has a greater effect on the abundance index than does ignoring differences in fishing efficiency among vessels. The stock assessment model that includes standardized indices has significantly larger log-likelihood and reduced pattern in residuals than the one that includes nominal indices, suggesting that replacing nominal indices with indices from a spatiotemporal model can improve the stock assessment for yellowfin tuna in the eastern Pacific Ocean.

International audience; Tunas are the focus of significant fisheries in the Pacific Ocean, where landings of four species - skipjack tuna (Katsuwonus pelamis), yellowfin tuna (Thunnus albacares), bigeye tuna (Thunnus obesus) and albacore tuna (Thunnus alalunga) - constitute approximately 70 % of the global tuna catch. Stock assessments for skipjack, yellowfin and bigeye tunas in the Pacific Ocean currently assume eastern and western stocks. For albacore tuna, separate North Pacific Ocean and South Pacific Ocean stocks are currently assumed. In each case, these geographic definitions reflect the historical development of fisheries management across the Pacific rather than biological considerations. There is widespread agreement that uncertainties surrounding the stock structures of these four tuna species could have important impacts on the population dynamics models used to assess their status and inform management options. Knowledge of stock structure is also essential for improved modelling of the effects of climate change on tuna distribution and abundance and associated implications for fisheries. This paper reviews current knowledge and understanding of the stock structures of skipjack, yellowfin, bigeye and South Pacific albacore tunas in the Pacific Ocean, by exploring available literature relating to their biology, movement and spatial dynamics. As a guide for future research in this area, we identify the main uncertainties in defining the stock structure of these four tunas in the Pacific, including i) spawning dynamics; ii) the degree of spawning area fidelity and localised residency; iii) the provenance of individuals in, and proportional contributions of self-replenishing populations to, fishery catches within the Pacific Ocean; iv) linkages with adjacent 'stocks', v) the effects of climate change on stock structure and proportional contributions of self-replenishing populations to fisheries; and vi) the implications of improved knowledge of tuna stock structure for stock assessment and climate change model assumptions and fisheries management. We also briefly propose some approaches that future studies could use to address these uncertainties.

This study aimed to understand the size-specific spatiotemporal dynamics of bigeye tuna (Thunnus obesus) in the eastern Pacific Ocean from 1991 to 2017. A spatiotemporal delta-generalized linear mixed model was applied to catch rate data by size class collected from a Japanese longline fishery. The results showed that the density of bigeye tuna varied spatially across the eastern Pacific Ocean, with spatial segregation by size. The mean predicted density by size in the study area (100–150 °W, 10 °S–10 °N) indicated that adult fish (fork length (FL) > 152 cm) were mainly distributed in the middle of this study area, 110–140 °W in both hemispheres. For the intermediate size stage (FL > 115 to

The reproductive biology of Epinephelus morio (red grouper) and Mycteroperca bonaci (black grouper) were evaluated based on 533 specimens collected from artisanal fisheries landings in the Abrolhos Bank, Brazil, between May 2005 and September 2012. Sex ratio for the black grouper was 1:14 (n = 155 females and 11 males; 26.1–147 cm TL) and 1:10 for the red grouper (n = 334 females and 33 males; 15.0–96.0 cm TL). For both species, highest values of the gonadosomatic index (GSI) for females were recorded between July and October, indicating spawning during the austral winter. The length at first maturity (L50) for females was estimated at 62.0 and 47.0 cm TL for the black and red grouper, respectively. Batch fecundity based on TL and TW ranged from 2 to 15.4∗106 and 1.5 to 13.7∗106 for the black and red grouper, respectively. Interviews with experienced fishers revealed that spawning seasons of both groupers are largely unrecognized. Results demonstrate a positive relationship between GSI peaks, lower temperatures and stronger winds. The information provided herein may help decision-making regarding fisheries management and conservation for E. morio and M. bonaci at various levels of governance in the Abrolhos Bank, the region with the largest and richest coralline reefs in the South Atlantic.

Otolith-based methods combined with catch lengths were used to produce three simple fishing indicators for assessing stock status of the lane snapper Lutjanus synagris in the Abrolhos Bank, central Brazilian coast. Fish were obtained during landings between May 2005 and June 2007. Marginal Increment Analyses combined with edge analysis on sectioned otoliths (n = 303) confirmed annulus formation in an annual basis during June-October. Lane snapper were aged up to 18 years and the largest fish measured 56 cm total length. Growth was not significantly different between sexes, and the von Bertalanffy growth equation was derived as Lt = 56[1-e (−0.22(t−0.0)) ]. Highest cohort yield was achieved between 33.5–41.4 cm (optimal length) at ages 4–6. Age at first maturity was 2.8 years, and generation length was 10 years. Instantaneous total mortality (Z) was 0.58 year −1 and natural mortality rate (M) ranged from 0.17–0.36 year −1 . Overall indicators point out for the need to implement fish management, as 30% of catch are composed of immature individuals and 7–12% by mega-spawners. A slot limit for the lane snapper in Abrolhos Bank is proposed, with restrictions for individuals 50 cm.

Weighting of size-composition data (length or weight composition of the catches) can have a large influence on the results of contemporary integrated stock assessment models in the presence of model misspecification. Model misspecification leads to conflicting information among data sets, and the choice of data weighting will determine the results. Information content on absolute abundance and abundance trends contained in size-composition data is particularly susceptible to misspecification of the biological processes. Biological processes are often misspecified in assessment models for exploited fish stocks due to lack of information. The misspecification can be in a functional form (e.g., the growth curve) or in the values assumed for pre-specified parameters. Our application to bigeye tuna in the eastern Pacific Ocean shows how one needs to “get the biology right”, i.e. minimize model misspecification, to reduce the dependency of stock assessment results on the weighting of the various data components. The stock assessment results are sensitive to the conversion from processed weight to total weight, a common, but often overlooked, component of model specification, and to the asymptotic length of the growth curve. The results are also sensitive to the weighting of the composition data. Application of the Age-Structured Production Model diagnostic shows that recruitment variation must be taken into account to interpret the absolute abundance and trend information contained in a CPUE-based index of relative abundance. Unfortunately, recruitment cannot typically be estimated from the relative index of abundance alone, so composition data are needed. The abundance estimates from an age-structured production model with estimated recruitment deviates are too uncertain (i.e., have wide confidence intervals) to be of use for management advice. Therefore, there is a trade-off between using composition data to estimate recruitment and its influence on estimates of absolute abundance through a catch-curve type process. We conclude that (i) integrated analysis, the current approach for assessing fish stocks, is supported by our results; (ii) composition data are needed to estimate recruitment; and (iii) addressing key model misspecifications should be a major component of integrated analysis.

Delineating the stock structure of highly-mobile, wide-ranging fishes subject to exploitation is a challenging task, yet one that is fundamental to optimal fisheries management. A case in point are stocks of skipjack tuna (Katsuwonus pelamis), yellowfin tuna (Thunnus albacares), bigeye tuna (Thunnus obesus) and albacore tuna (Thunnus alalunga) in the Pacific Ocean, which support important commercial, artisanal, subsistence, and recreational fisheries, and contribute roughly 70 % of global commercial tuna catches. Although some spatial and temporal structuring is recognised within these stocks, growing evidence from a range of approaches suggests that the stock structure of each tuna species is more complex than is currently assumed in both stock assessment and climate change models, and in management regimes. In a move towards improving understanding of the stock structure of skipjack, yellowfin, bigeye and South Pacific albacore tunas in the Pacific Ocean, an international workshop was held in Nouméa, New Caledonia, in October 2018 to review knowledge about their movement and stock structure in the region, define and discuss the main knowledge gaps and uncertainties concerning their stock structure, and develop biological sampling approaches to support the provision of this information. Here, we synthesise the discussions of this latter component. For each tuna species, we identify several general sampling considerations needed to reduce uncertainty, including i) the need for broadscale sampling in space, ideally covering each species’ distribution, targeting adults in spawning condition and adopting a phased approach; ii) the need for temporally-repeated sampling of the same geographical areas to assess stability in observed patterns over time; iii) the need to resolve patterns in spatial dynamics, such as those resulting from movements associated with the seasonal extensions of poleward flowing currents, from underlying stock structure, iv) the importance of adopting a multidisciplinary approach to stock identification, and v) the need for careful planning of logistics and coordination of sampling efforts across agencies. Finally, we present potential sampling designs that could be adopted to help overcome uncertainties around the initial identification of stocks and the provenance, mixing and proportional contributions of individuals in harvested assemblages, as well as how these uncertainties could be accounted for in fisheries management via the use of management strategy evaluation., Funding support for the workshop was provided by Conservation International as part of the GEF-funded, World Bank-implemented Ocean Partnerships for sustainable fisheries and biodiversity conservation (OPP), a sub-project of the Common Oceans ABNJ Program led by UN-FAO.

The Brazilian-endemic greenbeack parrotfish, Scarus trispinosus Valenciennes, 1840, is the largest herbivorous reef fish in the South Atlantic. Following the sharp decline of large carnivorous reef fishes, parrotfishes (Labridae: Scarinae) were progressively targeted by commercial fisheries in Brazil, resulting in a global population decline of 50% for S. trispinosus. Most of its remnant population is concentrated in the Abrolhos Bank, where the present study was conducted. We present novel information on age, growth and the reproductive cycle of S. trispinosus, based on 814 individuals obtained from commercial fisheries’ landings and scientific collections, between 2010 and 2013. Sex ratio was biased toward females (1:8), and spawning occurred year-round with discrete peaks in February-March and June-December. Increment analysis indicated annual deposition of growth rings in otoliths, which presented 1–22 rings. The asymptotic length at which growth is zero (L∞) was estimated from a Bayesian logistic regression at 85.28 cm, growth rate (K) at 0.14 year−1, and the theoretical age at zero size (t0) at 0.16. Subregional demographic structuring was detected, with predominance of slower-growing individuals in shallower inshore reefs and predominance of faster-growing and older individuals in deeper offshore sites. We demonstrate that S. trispinosus is highly vulnerable to over-exploitation due to its large size, long live and slow-growth, and review the management measures proposed since its Red List assessment in 2012.

22 pages, 8 figures, 2 tables, supplementary material https://doi.org/10.1007/s11160-018-9539-9, Ecological models are useful for evaluating fishery management scenarios, as they allow researchers to investigate alternative fishing effort, as well as varying environmental and trophic interaction scenarios. Through an ecosystem modeling approach (Ecopath with Ecosim), we addressed the possible impacts of small-scale fisheries on the structure and functioning of a tropical ecosystem (Itaipu Reservoir, Brazil). We found that fishing effects and predator–prey interactions were the main drivers explaining catch trends in the Itaipu Reservoir fisheries. The mean trophic level of catch did not change throughout the analyzed time period and no losses in secondary production from exploitation (L index) were observed, indicating that Itaipu fisheries are sustainable regarding ecosystem effects. The negative impacts of introduced species on native species seem to be greater than the fishing impacts. Fishing simulations from the ecosystem Maximum Sustainable Yield (MSY) reduced the biomass of some important species in the local fishery. Regarding management advice, our results indicate that fishing efforts should not be increased for curimba (Prochilodus lineatus), pintado (Pseudoplatystoma corruscans), and jaú (Zungaro jahu). Additionally, participative management methods are important measures for local fisheries. Finally, additional research is needed to investigate how fishery management can promote the use of multispecific methods (e.g., gillnets) to control introduced species, This paper is part of the Ph.D. thesis of JSP under the supervision of CMV at University of Maringá (UEM-Brazil) with scholarship supported by Coordination forthe Improvement of Higher Education Personnel (CAPES) toJSP CAPES also supported MC (Proc. PVE A063/2013, Ed.71/2013)

To better understand the ecology and biology of the curimba in the Parana River and to provide basic information for fisheries stock assessment, this study address the following questions: Do age estimates derived from otoliths and scale agree for Prochilodus lineatus? What is the growth trajectory for curimba in the upper Parana River? What is the age structure of the population in the upper Parana River? Is there any evidence of spatial stratification in population age structure or growth? Fish were sampled in the Parana, Ivinhema and Baia Rivers and in the Itaipu reservoir from 2012 to 2013. The otoliths showed one to eight annuli and the scales had one to six circuli. The agreement between the otoliths was higher (about 80%) than between the scales (about 70%). The agreement between otolith and scale readings was significantly low (about 40%). Using a von Bertallanfy growth function, the asymptotic standard length (L∞) for the whole population was estimated to be 68.84 cm, the growth coefficient (K) was estimated to be 0.15 year−1 and t0 was assumed to be 0 year. There was substantial variation in length-at-age in most but the youngest ages, in the intermediate ages there was a mix of individuals from various locations with markedly different growth rates. Our data also suggest a recruitment failure in 2012 and 2013, due to the lack to flooding, which also caused lack of habitat connectivity.

Variation in individual growth rates contributes to changes over time in compensatory population growth and surplus production for marine fishes. However, there is little evidence regarding the prevalence and magnitude of time-varying growth for exploited marine fishes in general, whether it is best approximated using changes in length-at-age or weight-at-length parameters, or how it can be represented parsimoniously. We therefore use a database of average weight in each year and age for 91 marine fish stocks from 25 species, and fit models with random variation in length and weight parameters by year, age, or cohort (birth-year). Results show that year effects are more parsimonious than age or cohort effects and that variation in length and weight parameters provide roughly similar fit to average weight-at-age data, although length parameters show a greater magnitude of variability than weight parameters. Finally, the saturated model can explain nearly 2/3 of total variability, while a single time-varying factor can explain nearly 1/2 of variability in weight-at-age data. We conclude that time-varying growth can often be estimated parsimoniously using a single time-varying factor, either internally or prior to including ‘empirical’ weight at age in population dynamics models.

In the eastern tropical Pacific Ocean, yellowfin tuna ( Thunnus albacares ) are often found in association with spotted ( Stenella attenuata ) and spinner ( Stenella longirostris ) dolphins. Purse-seine vessels use this co-occurrence to locate the tuna by searching for dolphins and associated birds. Data collected by onboard observers since the late 1970s were used to develop indices of relative abundance for dolphins, based on line-transect methodology, when the primary method of detection of dolphin herds was with binoculars. However, trend estimation was subsequently discontinued in 2000 due to concerns about changes in reporting rates of dolphin herd detections with increased use of helicopter and radar search. At present, as a result of a hiatus in fishery-independent surveys since 2006, fisheries observer data are the only source of information with which to monitor the status of eastern tropical Pacific Ocean dolphin populations. In this paper, trend estimation with the onboard observer data is revisited using a sightings-per-unit-effort approach. Despite different assumptions and model structure, the results indicate a lack of independence between the distribution of search effort and the search methods used, and the abundance of dolphin herds associated with tunas, on several spatial and temporal scales. This lack of independence poses a considerable challenge to the development of a reliable index of relative abundance for dolphins with these data. Given these results, alternatives for dolphin abundance estimation are discussed. One alternative is the use of purse-seine vessels for line-transect surveys during fishery closure periods. Another alternative is the use of purse-seine vessels during normal fishing operations as platforms for the collection of mark-recapture data ( e . g ., passive integrated transponder tags or genetics sampling). Life-history data collection, as a supplement to the collection of other data types, is also discussed. Further research and development is needed to assess whether these alternative methods will be useful.

We describe and illustrate a spatio-temporal modelling approach for analyzing age- or size-specific catch-per-unit-effort (CPUE) data to develop indices of relative abundance and associated composition data. The approach is based on three concepts: 1) composition data that are used to determine the component of the population represented by the index should be weighted by CPUE (abundance) while the composition data used to represent the fish removed from the stock should be weighted by catch; 2) due to spatial non-randomness in fishing effort and fish distribution, the index, index composition, and catch composition, should be calculated at a fine spatial scale (e.g., 1°x1°) and summed using area weighting; and 3) fine-scale spatial stratification will likely result in under-sampled and unsampled cells and some form of smoothing method needs to be applied to inform these cells. We illustrate the concepts by applying them to yellowfin tuna (Thunnus albacares) in the eastern Pacific Ocean.

Here we choose the sábalo Prochilodus lineatus, to answer the following questions: How the otolith length and weight are correlated to fish measurements (length and weight)? How reliable are the otoliths measurements to predict the length and age of P. lineatus? Finally, we propose predictive equations of the length and weight of the fish using length and weight of the otolith. The otoliths were sampled from individuals collected in the Upper Paraná River floodplain during 2012 and 2013 years. The relationships among the otolith measurements and both length and weight of the fish were performed using linear regressions. To test whether the length and weight of the otolith differ between the sampled sites, Variance Analysis was performed. Finally, we made analysis of Kruskal-Wallis to verify if the measurements obtained through the otoliths could be used to distinguish the age of the fish. We demonstrate that the length and weight of the otolith are good proxies to predict the length and weight of the fish. Although some ages were statistically different, this result does not support the idea that the age of the fish can be accurately inferred only using otolith measures. RESUMO Neste trabalho o curimba Prochilodus lineatus foi utilizado para responder as seguintes questões: Como o comprimento e o peso dos otólitos são correlacionados com o comprimento e o peso do peixe? Até que ponto as medidas dos otólitos são confiáveis para predizer a idade do P. lineatus? Finalmente, nós propomos equações preditivas do comprimento e peso do peixe utilizando o comprimento e o peso do otólito. Os otólitos foram amostrados de indivíduos coletados na planície de inundação do alto rio Paraná durante os anos de 2012 e 2013. As relações entre as medidas dos otólitos e o peso e comprimento do peixe foram verificadas utilizando regressões lineares. Para testar se o comprimento e o peso do otólito diferem entre locais foram utilizadas Análises de Variância e para testar se as medidas dos otólitos são suficientes para distinguir as idades foram utilizados testes de Kruskal-Wallis. Nós demonstramos que o comprimento e o peso do otólito são bons preditores do comprimento e peso do peixe. Embora algumas idades foram estatisticamente diferentes entre as medidas dos otólitos, esse resultado não suporta a ideia de que a idade do peixe pode ser inferida de forma acurada somente utilizando as medidas dos otólitos.

We present the growth cessation model, which is designed for species, such as some tropical tunas, that have an apparent linear relationship between length and age, followed by a marked reduction of growth after the onset of sexual maturity. The growth curve simply assumes linear growth for the youngest individuals and then uses a logistic function to model how the growth rate falls to zero at greater ages. One characteristic of the model is that, as t → 0, the model converges to a linear regression. The range of ages for which a linear regression adequately represents the mean length at age depends on when the logistic function becomes influential. A beneficial characteristic of this model is that, unlike other growth models, a preponderance of younger fish may not overwhelm the information from older fish, which biases the estimates of mean length at age for older fish. We apply the growth curve to bigeye tuna (Thunnus obesus) data from the eastern Pacific Ocean, obtained from otolith daily increment counts and tagging experiments, and compare the results with those from the von Bertalanffy and Richards growth curves. The growth cessation model fits the eastern Pacific Ocean bigeye tuna data better than do the von Bertalanffy and Richards growth curves. These results support the use of the growth cessation model for bigeye tuna in the eastern Pacific Ocean, and since many species have growth curves that flatten out to the point where growth is almost undetectable, this indicates that the growth cessation model may be widely applicable.

The exploitation status of marine fisheries stocks worldwide is of critical importance for food security, ecosystem conservation, and fishery sustainability. Applying a suite of data-limited methods to global catch data, combined through an ensemble modeling approach, we provide quantitative estimates of exploitation status for 785 fish stocks. Fifty six percent (439 stocks) are below BMSY and of these, 261 are estimated to be below 80% of the BMSY level. While the 178 stocks above 80% of BMSY are conventionally considered “fully exploited”, stocks staying at this level for many years, forego substantial yield. Our results enable managers to consider more detailed information than simply a categorization of stocks as “fully” or “over” exploited. Our approach is reproducible, allows consistent application to a broad range of stocks, and can be easily updated as new data become available. Applied on an ongoing basis, this approach can provide critical, more detailed information for resource management for more exploited fish stocks than currently available. This article is protected by copyright. All rights reserved

The small quantity of basic studies like age and growth estimates implies a lack of stock assessments and difficulties to make decisions related to fisheries management and biodiversity conservation. Therefore, we extensively and systematically reviewed the growth parameters of freshwater species from South America, with the following objectives: verify the existence of taxonomic patterns between asymptotic length and the growth coefficient; summarize the principal methods used and identify tendencies in their use; analyze the time between collection of the data and publication of the results; and verify possible latitudinal patterns in asymptotic length and the growth coefficient. A total of 199 articles covering 259 species were found. This work demonstrates the main gaps in the age and growth studies of freshwater fish from South America. Although there are well-studied basins such as Parana and some parts of the Amazon, most of the ecoregions remain without information or basic studies, and show the need for efforts to improve this situation to better understand the population dynamics of the species. Considering the L∞-K relationship, no evident latitudinal patterns were found, not even for species of the same order. Still, despite the wide use that the growth parameters have in the most diverse models and population studies, our analyses show that the data take a long time to be published, making more applied management and conservation studies unfeasible or, at least, harder. Finally, growth parameter data can contribute to minimize the lack of stock assessments, providing important information for use in management and biodiversity conservation.

Ecological risk assessment (ERA), including Productivity-Susceptibility Analysis (PSA), is becoming increasingly used to assess the relative vulnerability of data-limited non-target species to the impacts by fishing. PSA was developed for the eastern Pacific Ocean (EPO) tuna purse-seine fishery to assess the vulnerability of incidentally-caught species for three set types, “dolphin sets”, “unassociated sets” and “floating-object sets”, during 2005–2013. Because of operational differences between these set types, susceptibility values were combined for each species across the three set types to produce an overall fleet-wide susceptibility estimate. Vulnerability was highest for elasmobranchs, namely the giant manta ray, bigeye and pelagic thresher sharks, smooth and scalloped hammerhead sharks, and silky shark. Billfishes, dolphins, other rays, ocean sunfish, and yellowfin and bigeye tunas were classified as moderately vulnerable while the remaining species, all teleosts, had the lowest vulnerability scores. This purse-seine fleet-wide PSA identified potentially vulnerable species that can be compared with PSAs for other fisheries operating in the EPO, once detailed catch information becomes available for those fisheries. Such information can assist managers with prioritising fishery- and species-specific research programs and/or mitigation measures.

Application of sidescan sonar at the regional scale of the Abrolhos Bank, with ground-truthing by remotely operated vehicles and mixed-gas diving operations, revealed a much more complex habitat mosaic than previously recognized. The regional benthic habitat map indicates 8844 km2 of reefs (earlier estimates from remote sensing were around 500 km2) and 20,904 km² of rhodolith habitat—the world's largest continuous bed. Integration of the regional megahabitat map with spatially explicit data on the distribution of marine protected areas (

In this study we tested the basic premise that fishers’ knowledge provides similar perceptions about exploited stocks to data gathered by standardised monitoring in a small-scale commercial fishery. To that end, we compared temporal trends in catch and individual size for fish species between data obtained from interviews with fishers and a 25-year dataset from a landing monitoring program in the Itaipu Reservoir (Brazil). Fishers described with accuracy changes in species composition of the catches, from large migratory species of high commercial value (common before impoundment) to migratory species of low commercial value and sedentary species following damming. Temporal trends in catches reported by fishers and documented in the landing data matched for most species. Histories diverge when absolute values are involved, such as when fishers were asked to recall their largest catch. Fishers were homogeneous in their reports, indicating that instead of individual opinions, they revealed knowledge resulting from their observation and fishery experience. Fishers can be a reliable source of information for detecting changes in catches over time, especially when large-scale habitat changes have occurred within the time scale of a fisher career. Fishers may be key partners to be considered by managers in information gathering for effective management.

The mathematical and statistical advances in fitting stock assessment models enabled the emergence of the paradigm of “integrated analysis”, which fits all available data to a single model of population dynamics that traditionally has total catch as the only forcing function of the system. This approach, however, allowed us to include, in a flexible way, the effect of hydrological regime as an additional forcing function. We tried to achieve this flexibility by making the annual recruitment rates and spawning biomass adjustable to the attributes of the hydrological cycle data. Our models showed that these attributes are influential in the population dynamics of Brycon hilarii of the Northern Pantanal, and their inclusion in the models allowed best partial fits (which considered fits only to the data components length- and age-compositions, CPUE of juveniles and adults) than the Base-case (without hydrological attributes). The best partial fits where obtained when the attributes “delay of floods” and “intensity of floods” were forcing the spawning biomass and the annual recruitment respectively, indicating that these characteristics of the population may be influenced by specific attributes of the water level. The use of integrated modeling contributed with the advancement of population ecology knowledge of rheophilic fish. It is recommended that freshwater fisheries management be integrated into the hydrology management.

Freshwater fisheries are mainly small-scale activities and occur mostly in developing countries. These fisheries are recognized for its chronic lack of data and incipient knowledge when compared to large-scale fisheries, despite its socioeconomic and food security relevance. Brazil is a good model of small-scale freshwater fisheries country because it shares similar characteristics and shortcomings of many other countries in South America, Africa and Asia, where these activities prevail. This work aims to carry out a broad and comprehensive analysis of the approaches and limitations of Brazilian freshwater fisheries studies through a scientometric analysis. We conducted an exhaustive survey of scientific platforms such as the Web of Knowledge Thomson Reuters (ISI), Scientific Electronic Library Online (SciELO), Google Scholar and CNPq Lattes Curriculum Vitae Database. We found that the platforms ISI and SciELO were limited for this area of knowledge as they recovered only 47 % of the 186 studies reviewed. Brazilian freshwater fisheries studies were published in 72 journals and were conducted by 234 researchers, with very few specialists. On average the data processing into scientific information took 5 years, and half of the studies were conducted in short time scale (less than 2 years long) mostly by research institutions and universities. The number studies declined since the year 2008, after the creation of the Ministry of Fisheries and Aquiculture, which indicate that the fallacy of disregarding scientific knowledge may be permeating decision making agencies as already happen in the past in Brazil. The combination of these factors may cause slow and inefficient decision-making and management based on the best available science. Our results also highlighted the importance of multidisciplinarity in the training of human resources to work in the fishing sector.

The early life history of Western Atlantic snappers from the Southern hemisphere is largely unknown. Habitat use of different life stages (i.e. size categories) of the dog snapper (Lutjanus jocu) was examined across the largest South Atlantic reefeestuarine complex (Abrolhos Shelf, Brazil, 16e19 � S). Visual surveys were conducted in different habitats across the shelf (estuary, inner-shelf reefs and mid-shelf reefs). Lutjanus jocu showed higher densities on inner-shelf habitats, with a clear increase in fish size across the shelf. Individuals 40 cm were recorded only on midshelf reefs. Literature data indicate that individuals ranging 70e80 cm are common on deep offshore reefs. This pattern suggests that the dog snapper performs ontogenetic cross-shelf migrations. Protecting portions of the different habitats used by the dog snapper during its post-settlement life cycle is highlighted as an important conservation and management measure.

Although information on the spawning seasons of commercially important snappers (Lutjanidae) and groupers (Serranidae, subfamily Epinephelinae) is available for the north and central west Atlantic, there is little information for the tropical western South Atlantic (Brazil). As a consequence, there are few fishery regulations in this entire region that take into consideration such information. In this study, we characterized the reproductive cycles of three Epinephelinae serranids (Epinephelus morio, Mycteroperca bonaci and Cephalopholis fulva) and five lutjanids (Lutjanus synagris, L. jocu, L. analis, Ocyurus chrysurus and Rhomboplites aurorubens) that occur in the Abrolhos Bank, Brazil, the largest reef complex in the tropical western South Atlantic. A total of 3528 gonads were collected from May 2005 to October 2007. Temporal variability in spawning patterns was evaluated using the Gonadosomatic Index (GSI) and macroscopic analyses. The peak of reproductive activity for the three grouper species occurred between July and August. Snappers exhibited two peaks of reproductive activity, the more intense of which occurred between September and October. The other peak occurred between February and March, with the exception of the deep-dwelling species R. aurorubens, which only reproduced between February and March. Seasonal patterns were consistent over the two consecutive years that we studied, and these patterns are equivalent to those observed for the Northern Hemisphere, as are the sizes at maturity and at the time of sexual change (for the three protogynous hermaphrodite groupers). Fisheries management in this region could be significantly improved by a combination of catch and effort limitations being imposed during spawning seasons and by overall size limitations, particularly considering that most of the fish caught are generally below size at maturity. The proposed buffer zones for the marine areas that are presently protected in Abrolhos represent an opportunity for implementing both spatial (e.g. setting no-take zones that cover spawning sites) and temporal (e.g. seasonal closures during spawning peaks) management tools, using a participatory approach at the regional scale. A pesar de que se tiene un buen conocimiento sobre la época de freza de los pargos (Lutjanidae) y los meros (Serranidae, subfamilia Epinephelinae) en las zonas norte y central del Atlántico occidental, la información disponible del Atlántico suroccidental es escasa. Como consecuencia, en esta zona aún existen pocas regulaciones pesqueras que tengan en cuenta esta información. En este estudio se caracterizan los ciclos reproductores de tres serránidos Epinephelinae (Epinephelus morio, Mycteroperca bonaci and Cephalopholis fulva) y cinco pargos (Lutjanus synagris, L. jocu, L. analis, Ocyurus chrysurus and Rhomboplites aurorubens) en el Banco de Abrolhos, el mayor complejo de arrecifes del Atlántico suroccidental. Se examinaron un total de 3528 gónadas entre mayo de 2005 y octubre de 2007. La variabilidad temporal de las pautas de puesta se evaluó mediante el Índice Gonadosomático (GSI) y análisis microscópicos. Para los tres meros el máximo en la actividad reproductora se produce entre julio y agosto. Los lutjánidos presentan dos picos de actividad bien diferenciados, siendo el más intenso el que tiene lugar entre septiembre y octubre, mientras que el menor se produce entre febrero y marzo, con la excepción de R. aurorubens, una especie de profundidad, que sólo se reproduce entre febrero y marzo. Las pautas estacionales en la reproducción son consistentes en los dos años consecutivos y, junto a la edad de primera madurez y la edad de inversión sexual (los tres meros son hermafroditas proterogínicos), son equivalentes a las que se producen en el hemisferio septentrional. La gestión pesquera en esta región podría mejorar significativamente mediante una combinación de limitaciones en las capturas y en el esfuerzo durante las épocas de puesta, así como limitando la talla mínima de captura, considerando que la mayoría de individuos capturados actualmente son inmaduros. Las zonas de amortiguación de las áreas marinas actualmente protegidas en Abrolhos representan una buena oportunidad para implementar herramientas de gestión tanto espaciales (e.g. estableciendo zonas de exclusión pesquera en los lugares de freza) como temporales (e.g. prohibiendo la pesca durante la época de reproducción), utilizando una aproximación participativa a una escala regional.

The invasion process comprises not only the characteristics of nonindigenous species but also the attributes of the invaded environment which make it susceptible to the establishment of nonindigenous species. Habitat attributes operate like filters in determining the establishment of introduced species and the invasibility of a region. In the Upper Parana River Basin, Brazil, the practice of introducing species was quite common and frequently carried out by hydroelectric companies. The target species of the present study, the peacock-bass Cichla kelberi, is native to the Amazon Basin. This species was introduced into several reservoirs of the Upper Parana River Basin and is dispersing rapidly throughout the system. This study shows which characteristics of the reservoirs facilitate their invasibility after testing for the effect of propagule pressure. We conclude that a set of abiotic factors favors the invasibility of these reservoirs. To be more precise, the largest, deepest, most transparent and warmest reservoirs are the most likely to be colonized by Cichla kelberi. It is possible that other environments with similar characteristics to these reservoirs, such as the lagoons from the Upper Parana River Basin floodplain, can also be colonized by Cichla kelberi.

In Brazil, Marine Extractive Reserves—MERs (Reservas Extrativistas Marinhas) represent the most significant government-supported effort to protect the common property resources upon which traditional small-scale fishers depend. From an initial small-scale experience in 1992, MERs have expanded countrywide, now encompassing 30 units (9,700 km2) and nearly 60,000 fishers. Despite such escalating interest in the model, there is little research on the effectiveness of MERs. In this article, we discuss relevant parts of the history and examine the current situation of the fisheries co-management initiative in the Marine Extractive Reserve of Corumbau, which was created in 2000 as the first MER to encompass coral reefs and reef fisheries. We describe the Extractive Reserve co-management arrangement and its main policy and legislative challenges. Finally, we discuss the prospects for the use of MERs as management frameworks for traditional small-scale fisheries in Brazil.

Our aim was to devise visual sampling protocols to estimate densities in a morphologi- cally and behaviorally diverse assemblage of reef fishes. The focus was on a design that is cost- effective and produces relatively accurate and precise density estimates for the largest number of species. We evaluated the 2 most widely used shapes of sampling units (strip transects and stationary cylinders) of several dimensions on a fringing reef at Fernando de Noronha Archipelago, tropical West Atlantic. Small sampling units produced the best density estimates for small fishes, while large ones produced the best estimates for large fishes, regardless of sampling unit shape. The sampling unit with the lowest cost was the stationary cylinder. We further compared accuracy and precision of density and richness estimates from several combinations of stationary cylinders and fish size. A simple improvement in stationary censuses, i.e. a sampling unit composed of 2 nested cylinders (2 m and 4 m radii, respectively), enhanced the accuracy and precision of estimates. Counts of small fish (≤10 cm) were made in the smaller cylinder and counts of larger fish (>10 cm) were made in the larger. Such nested cylinders reduce the bias towards large and conspicuous species and allow for separate density estimates for adults and juveniles of large species.

We assessed spatial and temporal variability in the physical environment of a subarctic estuary, and examined concurrent patterns of chlorophyll abundance (Xuorescence), and zooplankton and forage Wsh community structure. Surveys were conducted in lower Cook Inlet, Alaska, during late July and early August from 1997 through 1999. Principle components analysis (PCA) revealed that spatial heterogeneity in the physical oceanographic environment of lower Cook Inlet could be modeled as three marine-estuarine gradients characterized by temperature, salinity, bottom depth, and turbidity. The gradients persisted from 1997 through 1999, and PCA explained 68% to 92% of the variance in physical oceanography for each gradient–year combination. Correlations between chlorophyll abundance and distribution and the PCA axes were weak. Chlorophyll was reduced by turbidity, and low levels occurred in areas with high levels of suspended sediments. Detrended correspondence analysis (DCA) was used to order the sample sites based on species composition and to order the zooplankton and forage Wsh taxa based on similarities among sample sites for each gradient–year. Correlations between the structure of the physical environment (PCA axis 1) and zooplankton community structure (DCA axis 1) were strong (r D 0.43–0.86) in all years for the three marine-estuarine gradients, suggesting that zooplankton community composition was structured by the physical environment. The physical environment (PCA) and forage Wsh community structure (DCA) were weakly correlated in all years along Gradient 2, deWned by halocline intensity and surface temperature and salinity, even though these physical variables were more important for deWning zooplankton habitats. However, the physical environment (PCA) and forage Wsh community structure (DCA) were

Meta-analysis is an important new tool for synthesizing scientific knowledge from many previous studies. In fisheries, meta-analyses can be used to obtain prior distributions or penalty functions for parameters used in stock as- sessment models. Two types of results are generally published in a meta-analysis: Type A, the updated results for each stock used in the meta-analysis, and Type B, the results that would best describe a new stock. Including these results in assessments for the individual stocks would result in double use of the data if the assessments include the input data used in the meta-analyses, which they typically would. To solve this problem, we recommend that an additional form of results should be reported in meta-analyses: Type C, the results for a new stock obtained by sequentially excluding each stock's data set and repeating the meta-analysis. Type C results should be used whenever the assessment input data overlap with the meta-analysis input data, avoiding the double use of data. We illustrate the impact of this report- ing change on the results of a recent meta-analysis. Resume : La meta-analyse est un nouvel outil precieux pour faire la synthese des informations scientifiques contenues dans un grand nombre d'etudes anterieures. Dans le cas des peches, les meta-analyses peuvent servir a determiner des distributions a priori et des fonctions de penalite pour les parametres dans les modeles d'evaluation des stocks. On publie generalement deux types de resultats dans une meta-analyse, les premiers, de type A, les donnees mises a jour de chacun des stocks utilises dans la meta-analyse et les seconds, de type B, les resultats qui decriraient le mieux un nouveau stock. Inclure ces resultats dans des evaluations de stocks individuels reviendrait a utiliser deux fois les meme donnees, si les evaluations comprennent les donnees originales d'entree de la meta-analyse, ce qui arrive normalement. Pour eviter ce probleme, nous recommandons d'inclure un troisieme type de resultats dans les meta-analyses, le type C, soit les resultats pour un nouveau stock en excluant tour a tour les donnees de chaque stock et en repetant la meta- analyse. Les resultats de type C devraient etre utilises lorsque les donnees d'entree de l'evaluation chevauchent celles de la meta-analyse, ce qui permettrait d'eviter une double utilisation des donnees. Nous illustrons les effets de ce chan- gement de presentation sur les resultats d'une meta-analyse recente. (Traduit par la Redaction) Minte-Vera et al. 929

We assessed the structure of the fish assemblages in the Itaipu Reservoir (Parana River, Brazil-Paraguay) along a longitudinal or river-dam gradient (composed of riverine, transitional and lacustrine zones) and transversal or upstream–downstream gradients of the tributaries (composed of lotic and lentic stretches of tributaries and reservoir shores). We sampled stations distributed along the environmental gradients quarterly during two years. We caught mostly piscivorous, detritivorous and insectivorous fishes. The structure of the whole fish assemblage both at the regional spatial scale and at the zones of each gradient was significantly non-random according to null models and ordination analysis. When the assemblage was broken into groups, the piscivores and detritivores as well as the predators and prey showed significant non-random structure whereas the insectivores, omnivores, herbivores, benthophages and mud-eaters showed random structure. The first groups are those that had more species and the last mentioned are those with fewer species. The tributaries varied more in composition among themselves than the reservoir shores, showing a high heterogeneity in the transversal gradient. The most widespread species was the introduced piscivore Plagioscion squamosissimus. The loricariids were most abundant in the lotic and lentic stretches of the tributaries. We also observed temporal variability in species composition, mainly in the reservoir shores possibly due to the influence of the upstream floodplain on the migratory fish that periodically use the reservoir as feeding habitat. In the tributaries, the temporal changes were less predictable. A combination of habitat preferences and interactions among species, especially predator–prey relations, might be responsible for the observed structure patterns.

The total world catch from marine and freshwater wild stocks has peaked and may be slightly declining. There appear to be few significant resources to be developed, and the majority of the world's fish stocks are intensively exploited. Many marine ecosystems have been profoundly changed by fishing and other human activities. Although most of the world's major fisheries continue to produce substantial sustainable yield, a number have been severely overfished, and many more stocks appear to be heading toward depletion. The world's fisheries continue to be heavily subsidized, which encourages overfishing and provides society with a small fraction of the potential economic benefits. In most of the world's fisheries there is a “race for fish” in which boats compete to catch the fish before a quota is achieved or the fish are caught by someone else. The race for fish leads to economic inefficiency, poor quality product, and pressure to extract every fish for short-term gain. A number of countries have instituted alternative management practices that eliminate the race for fish and encourage economic efficiency, use lower exploitation rates that deliberately do not attempt to maximize biological yield, and encourage reduced fishing costs and increased value of products. In fisheries where this transition has taken place, we see the potential for future sustainability, but in those fisheries where the race for fish continues, we anticipate further declines in abundance, further loss of jobs and fishing communities, and potential structural change to marine ecosystems.

Billings Reservoir is an urban reservoir located in the Sao Paulo Metropolitan Region. It supports 101 active artisanal fishermen. To describe this fishery, landings were recorded daily between February 1996 and January 1997 at Colonia (23° 50′ 57′′ S; 46° 40′ 02′′ W). In every landing, a data collector recorded catch, effort, fishing gears and fishing grounds. A total of 147 593 kg of fish were recorded in 3515 fishing trips. The exotic Nile tilapia, Oreochromis niloticus (L.), was the main species exploited (81.4% of the annual catches). Five other species were also targeted: the characid Astyanax eigenmaniorum (Cope) (13.0% of the annual catches); the erythrinid Hoplias aff. malabaricus (Block) (2.1%); the exotic cyprinid Cyprinus carpio L. (Campos & Fernandez-Yepez) (2.4%); the curimatid Cyphocharax modestus L. (1.1%); and the pimelodid Rhamdia sp. (0.1%). Two main groups of fishermen were discriminated using Principal Components Analysis; these were associated with the type of fishing gear and fishing strategies, i.e. those who exploited Nile tilapia with cast nets and beating gill nets, and those who exploited other species with set gill nets. Management and maintenance of this fishery should consider the positive top-down effects that Nile tilapia could have in controlling eutrophication and also the social benefits.

Hydrochory was investigated in the seeds of the Amazonian floodplain tree, Swartzia polyphylla, in which pods open on the tree to release one large seed. Seeds collected from beach drift along the Rio Negro showed a high percentage of floaters (82%). Yet most seeds sank following collection from: adult trees (89%), unflooded ground under adults (96%), and flooded ground under adults (86%). The specific gravity of the seeds was near that of water, 1.04 ± 0.03 for sinkers and 0.98 ± 0.02 for floaters. The ability to float was correlated directly with the volume of the air pocket between the two cotyledons, which varied from 5.6 to 20.5 percent of the total seed volume. In a long-term floatation test lasting 81 days, 45 percent of the seeds never floated, 33 percent always floated, and 22 percent first sank for one week and then floated for at least one month. Seeds that never floated eventually rotted, but not until days 63-73. Seeds that were floating at day 81, regardless of how long they had been floating, were placed on moistened filter paper for 18 days during which time 36 percent germinated, 45 percent rotted, and 19 percent did neither but remained viable. These results suggest that S. polyphylla achieves dimorphism in flotation of its seeds, some sinking and some floating, by producing seeds of continuous variation in specific gravity around a mean close to 1.00. Seeds that float can be dispersed long distances along river margins, while those that sink may be moved only marginally from the parent tree. RESUMO Investigou-se a hidrocoria em sementes de Swartzia polyphylla, uma especie arborea das florestas inundadas da Amazonia. A vagem se abre na arvore soltando normalmente uma grande semente. Sementes coletadas nas linhas de deposiCaao da praia do Rio Negro mostraram alta porcentagem de flutuaCao (82%), enquanto a maioria das sementes coletadas diretamente da copa das arvores (89%), no solo sob as arvores (96%) e em solo alagado sob as arvores (86%) afundou. A gravidade especifica destas sementes foi bem proxima a da agua, 1.04 ± 0.03 para as que afundaram e 0.98 ± 0.02 para as que flutuaram. A habilidade de flutuaCao esteve diretamente relacionada ao volume relativo da bolsa de ar que existe entre os cotiledones, variando de 5.6 a 20.5 porcento do volume da semente. Em um teste de flutuaCao de longa duraCao (81 dias), 45 porcento das sementes nunca flutuararm, 33 porcento flutuaram durante todo o teste, 22 porcento inicialmente afundaram por uma semana e depois flutuaram ao menos por um mes. Algumas das sementes afundadas apodreceram, mas nao antes de 63 dias de incubaCao. As sementes que estavam flutuando no 81° dia foram colocadas em papel de filtro umido, destas 36 porcento germinaram, 45 porcento apodreceram, e 19 porcento ficaram viaveis (nao germinaram, nem apodreceram). Estes resultados sugerem que as sementes de S.polyphylla apresentam dimorfismo para flutuafao, algumas flutuaCao e outras afundando, sendo isto consequencia da produCao de sementes com uma variaCao continua de gravidade especifica em torno de uma media proxima a 1.0. As sementes que flutuam podem set dispersas a longas distancias ao longo das margens dos rios, enquanto aquelas que afundam podem ser apenas marginalmente afastadas marginalmente da arvore-mae.

The lack of a long term, comprehensive and reliable fisheries statistics system is a major impediment to fisheries management in Brazil. Fishing is one of the main activities throughout the country's coast, with predominance of small-scale, artisanal, multigear, and multispecies captures that are landed in a pulverized network of coastal villages. Brazil is also a hotspot of common names, another feature that challenges artisanal fisheries' monitoring. We combined taxonomic and ethnobiological information to support the implementation of an artisanal fisheries' monitoring program under the co-management framework of a Marine Extractive Reserve in Bahia State, Northeastern Brazil. We surveyed 141 fishing landings, recording 86 fish species (43 families) and 52 correspondences 1:1 between local and scientific names. Broad folk categories had an average of 5.1 specific names, with "cação" (shark) being the category with more specific names (24 names to six biological species). With the exception of species that make up the bycatch captured by shrimp trawling, fisherfolks are able to identify commercially important species from both fresh specimens and photos. Common names can be reliably used in fisheries monitoring programs, and their usage facilitates the participation of fisherfolks in surveys based on voluntary or compulsory declarations of captures A falta de um sistema compreensivo e confiável de estatísticas pesqueiras em longo prazo é um dos maiores dificultadores da gestão pesqueira no Brasil. A pesca é uma das principais atividades ao longo da costa do país, com predominância de capturas artesanais de pequena escala, envolvendo múltiplas artes e espécies, além de desembarques realizados em uma rede pulverizada de localidades costeiras. O Brasil também possui grande riqueza de nomes comuns, outra característica que complica o monitoramento da pesca artesanal. No presente trabalho, combinamos informações taxonômicas e etnobiológicas para apoiar a implementação de um programa de monitoramento da pesca artesanal recifal e costeira sob o arcabouço de cogestão de uma Reserva Extrativista Marinha no estado da Bahia, Nordeste do Brasil. Foram amostrados 141 desembarques e registradas 86 espécies de peixes (43 famílias), com 52 correspondências 1:1 entre nomes locais e científicos. Categorias de nomes comuns genéricos tiveram uma média de 5,1 nomes específicos locais, com "cação" sendo aquela com mais nomes específicos (24 nomes para seis espécies biológicas). Excetuando-se as espécies capturadas como fauna acompanhante do arrasto-de-camarão, observamos que os pescadores são capazes de identificar as espécies comercialmente importantes tanto a partir de espécimes quanto de fotografias. Os nomes comuns podem ser usados com segurança em programas de monitoramento de pescarias de pequena escala, sendo que seu uso facilita a participação dos pescadores em levantamentos baseados em declarações de captura, sejam elas voluntárias ou compulsórias.

The Abrolhos Bank (eastern Brazil) encompasses the largest and richest coral reefs of the South Atlantic. Coral reef benthic assemblages of the region were monitored from 2003 to 2008. Two habitats (pinnacles' tops and walls) were sampled per site with 3–10 sites sampled within different reef areas. Different methodologies were applied in two distinct sampling periods: 2003–2005 and 2006–2008. Spatial coverage and taxonomic resolution were lower in the former than in the latter period. Benthic assemblages differed markedly in the smallest spatial scale, with greater differences recorded between habitats. Management regimes and biomass of fish functional groups (roving and territorial herbivores) had minor influences on benthic assemblages. These results suggest that local environmental factors such as light, depth and substrate inclination exert a stronger influence on the structure of benthic assemblages than protection from fishing. Reef walls of unprotected coastal reefs showed highest coral cover values, with a major contribution of Montastraea cavernosa (a sediment resistant species that may benefit from low light levels). An overall negative relationship between fleshy macroalgae and slow-growing reef-building organisms (i.e. scleractinians and crustose calcareous algae) was recorded, suggesting competition between these organisms. The opposite trend (i.e. positive relationships) was recorded for turf algae and the two reef-building organisms, suggesting beneficial interactions and/or co-occurrence mediated by unexplored factors. Turf algae cover increased across the region between 2006 and 2008, while scleractinian cover showed no change. The need of a continued and standardized monitoring program, aimed at understanding drivers of change in community patterns, as well as to subsidize sound adaptive conservation and management measures, is highlighted.

Bats may exhibit different patterns of activity, considering aspects concerning niche dynamics as well as the establishment and permanence of the communities in the ecosystems. In this way, the present study analyzed the time and seasonal patterns of activity in different species of frequent phyllostomid bats in remnants of the stational semidecidual forest from the Upper Paraná River, Southern Brazil. Captures were performed between January and December, 2006, using 32 mist nets set above the soil along the nocturnal period during the four seasons of the year. The daily and seasonal patterns of activity of each species was modeled using generalized linear models with Poisson error. The best model was selected using Akaike's Information Criterion (AICc). Artibeus planirostris (Spix, 1823) did not exhibit a conspicuous time pattern, whereas A. lituratus (Olfers, 1818) was more frequent after the sixth hour and A. fimbriatus Gray, 1838 had an activity increase along the night. Platyrrhinus lineatus (E. Geoffroy, 1810) was registered during all sampling hours. Carollia perspicillata (Linnaeus, 1758) and Sturnira lilium (E. Geoffroy, 1810) were the most active during the first four hours. Concerning seasonal pattern, the highest activity of these species was verified during the summer. These data contribute to the information about the ecology of bats in the region, highlighting the high adaptive potential of the species studied in relation to the use of space throughout the night and in to variations in environmental conditions. Os morcegos podem exibir diferentes padrões de atividade, considerando-se aspectos relacionados à dinâmica de nicho e ao estabelecimento e permanência das comunidades nos ecossistemas. Assim, o presente estudo teve por objetivo investigar o padrão de atividade horária e sazonal em diferentes espécies de morcegos, frequentes em remanescentes de floresta estacional semidecidual do alto rio Paraná, sul do Brasil. As coletas foram realizadas entre janeiro e dezembro de 2006, com o auxílio de 32 redes armadas acima do solo, ao longo de todo o período noturno e nas quatro estações do ano. A análise dos dados contemplou o uso de modelos lineares generalizados Akaike's Information Criterion (AICc) e distribuição de Poisson. Artibeus planirostris (Spix, 1823) não exibiu um padrão horário conspícuo, enquanto A. lituratus (Olfers, 1818) foi mais frequente após a sexta hora e A. fimbriatus Gray, 1838 teve aumento da atividade ao longo da noite. Platyrrhinus lineatus (E. Geoffroy, 1810) foi registrado durante todas as horas de amostragem. Carollia perspicillata (Linnaeus, 1758) e Sturnira lilium (E. Geoffroy, 1810) foram mais ativos nas quatro primeiras horas. Em relação ao padrão sazonal, constatou-se maior atividade dessas espécies durante o verão. Esses dados contribuem com as informações acerca da ecologia dos morcegos na região e evidenciam o alto potencial adaptativo das espécies estudadas à variação de tempo e condições ambientais.

Ecomorphological patterns of the fish assemblage from the upper Paraná River floodplain, Brazil, were described and evaluated according to trophic (guilds), spatial (habitats) and phylogenetic (taxonomic distances) structures. The samples were obtained through the Long Term Research Project (LTER-CNPq/UEM/NUPELIA) in August and October 2001. Thirty-five species were analyzed from thirty-one morphological variables. Strong significant correlations (Mantel test) between morphology and trophic guilds and between morphology and taxonomy were found, while morphology and habitat revealed a weak correlation. However, the partial Mantel test showed that the correlations between morphology and trophic guilds persist even when the effect of taxonomy is discounted. The ecomorphological pattern shown by the Principal Component Analysis separated species according to locomotion structures used in feeding. At one extreme there are the piscivores and insectivores that exploit lentic habitats and have compressed bodies and well developed anal fins, while at the other there are detritivores and invertivores that exploit lotic and semi-lotic habitats and have depressed bodies and well developed pectoral, pelvic and caudal fins. Canonical Discriminant Analysis using ecomorphological variables successfully predicted 94.5% of the trophic guild ecomorphotypes, but only 57.1% of the habitat ecomorphotypes. These data indicate that the fish assemblage of the upper Paraná River floodplain is structured ecomorphologically mainly according to trophic structure rather than habitat. Este trabalho objetivou descrever e avaliar os padrões ecomorfológicos da assembleia de peixes da planície de inundação do alto rio Paraná, Brasil, analisando os efeitos das estruturas trófica (guildas), espacial (tipos de habitats) e filogenética (distância taxonômica). Trinta e cinco espécies foram analisadas a partir de 31 variáveis morfológicas obtidas de espécimes coletados em agosto e outubro de 2001 no âmbito do Projeto Ecológico de Longa Duração (PELD-CNPq/UEM/NUPELIA). O teste de Mantel revelou que há correlação significativa das distâncias morfológicas com guildas tróficas e distâncias taxonômicas, enquanto com os tipos de habitats a correlação se mostrou fraca. Contudo, o teste de Mantel parcial demonstrou que a correlação da morfologia com as guildas tróficas independe da filogenia. O padrão de diversificação ecomorfológica apresentado pela Análise de Componentes Principais revelou um gradiente ecomorfológico relacionado à locomoção associada à ecologia trófica. Em um extremo estão espécies de piscívoros e insetívoros que exploram preferencialmente habitats lênticos com corpos comprimidos e nadadeiras anais desenvolvidas, enquanto no outro extremo estão os detritívoros e invertívoros que exploram preferencialmente habitats lóticos e semi-lóticos e apresentam corpos deprimidos e nadadeiras peitorais, pélvicas e caudais desenvolvidas. A Análise Discriminante Canônica realizada com os índices ecomorfológicos previu com sucesso 94,5% dos ecomorfotipos relacionados às guildas tróficas e apenas 57,1% dos ecomorfotipos que exploram os diferentes habitats analisados. Conclui-se que a assembleia de peixes da planície de inundação do alto rio Paraná está estruturada ecomorfologicamente, revelando-se mais influenciada pela estrutura trófica do que pela espacial.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:42:19Z No. of bitstreams: 1 S1519-69842006000500007.pdf: 218509 bytes, checksum: 9c84f45f30b963df3954d5b015f6a3f3 (MD5) Made available in DSpace on 2013-08-22T18:42:19Z (GMT). No. of bitstreams: 1 S1519-69842006000500007.pdf: 218509 bytes, checksum: 9c84f45f30b963df3954d5b015f6a3f3 (MD5) Previous issue date: 2006-08-01 Made available in DSpace on 2013-09-30T19:29:25Z (GMT). No. of bitstreams: 2 S1519-69842006000500007.pdf: 218509 bytes, checksum: 9c84f45f30b963df3954d5b015f6a3f3 (MD5) S1519-69842006000500007.pdf.txt: 52345 bytes, checksum: f0f19718774144caa8035523993f7066 (MD5) Previous issue date: 2006-08-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T15:08:05Z No. of bitstreams: 2 S1519-69842006000500007.pdf: 218509 bytes, checksum: 9c84f45f30b963df3954d5b015f6a3f3 (MD5) S1519-69842006000500007.pdf.txt: 52345 bytes, checksum: f0f19718774144caa8035523993f7066 (MD5) Made available in DSpace on 2014-05-20T15:08:05Z (GMT). No. of bitstreams: 2 S1519-69842006000500007.pdf: 218509 bytes, checksum: 9c84f45f30b963df3954d5b015f6a3f3 (MD5) S1519-69842006000500007.pdf.txt: 52345 bytes, checksum: f0f19718774144caa8035523993f7066 (MD5) Previous issue date: 2006-08-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Neste artigo, foi calculada e comparada a renda média de pescadores de pequena escala, que operam em dois reservatórios urbanos no Brasil: na Represa Billings (127 km²), localizada na região metropolitana da cidade de São Paulo, e no Lago Paranoá (38 km²), localizado em Brasília (DF). Ambas as pescarias são baseadas em espécies exóticas, principalmente a Tilápia do Nilo, Oreochromis niloticus (mais de 80% das capturas). Os pescadores da Represa Billings têm um ganho médio diário de R$ 17,75 (U$ 8,4), empregando principalmente a rede-de-espera. Os pescadores do Lago Paranoá têm um ganho médio diário de R$ 46,58 (U$ 24,9), empregando principalmente a tarrafa. A renda dos pescadores de Brasília é estatisticamente superior à dos pescadores de São Paulo (P < 0.01). O lucro dessas pescarias é explicado pela natureza do reservatório (Paranoá ou Billings) e pelos dias de pesca. Devido ao aumento da violência na região metropolitana de São Paulo, as pescarias na Represa Billings estão desaparecendo. The income of small-scale fisheries of two urban reservoirs in Brazil: Represa Billings (127 km²) located in the metropolitan region of São Paulo, the capital city of the state of São Paulo and Lago Paranoá (38 km²) located in Brasília (DF), the capital city of Brazil were calculated and compared. Both fisheries are mainly based on the alien Nile tilapia Oreochromis niloticus (more than 80% of the total catch). Although these reservoirs are nearly 900 km apart, their native fish fauna belong to the Upper Paraná Province. The Represa Billings fishers have, on average, a daily profit of R$ 15.8 (U$ 8.4 mostly employing gill nets) and Lago Paranoá fishers R$ 46.6 (U$ 24.9, mostly employing cast nets), which is a statistically significant difference (P < 0.001). The profit of the fisheries is explained by the factor reservoir and covariate days of fishing. Due to the increasing violence in the metropolitan region of São Paulo, the Represa Billings fishery is vanishing. UNESP Departamento de Ecologia Escritório de Licenciamento de Atividades de Petróleo e Nuclear UEM NUPELIA UNESP Departamento de Ecologia