Prospecting sugarcane genes involved in aluminum tolerance

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Reproductive migration of fish and movement in a series of reservoirs in the Upper Parana River basin, Brazil

AbstractThis study evaluates the effectiveness of two fish passes at two hydropower dams (Canoas I and II) in the Upper Parana basin, which form part of a cascade of three reservoirs. Fish from 12 migratory species (3089 specimens) were captured during their ascending, reproductive migration and were tagged with hydrostatic tags. The recapture data (294 specimens over two consecutive years) showed that there is a strong tendency for the maintenance of ascending migration through reservoirs with fish passes but with differences in migratory activity within the same species. No eggs, larvae or juveniles of these species were found in samples collected over 5 years in the reservoirs above the fish passes. These data suggest that fish passes have contributed to the restoration of the migratory routes of adult fish but that in the absence of suitable spawning or nursery habitats for these species; they probably act as ecological traps and do not contribute to the recruitment of the species.

Temporal genetic structure and relatedness in the Tufted Duck Aythya fuligula suggests limited kin association in winter

Conspecific aggregation of waterfowl in winter is a common example of animal flocking behaviour, yet patterns of relatedness and temporal substructure in such social groups remain poorly understood even in common species. A previous study based on mark-recapture data showed that Tufted Ducks Aythya fuligula caught on the same day were re-caught together in subsequent winters more often than expected by chance, suggesting stable assortments of ‘socially familiar’ individuals between wintering periods. The genetic relationships within these social groups were not clear. Based on 191 individuals genotyped at 10 microsatellite markers, we investigated the temporal genetic structure and patterns of relatedness among wintering Tufted Ducks at Lake Sempach, Switzerland, in two consecutive winters. We found no evidence of genetic differentiation between temporal groups within or between winters. The average levels of relatedness in temporal groups were low and not higher than expected in random assortments of individuals. However, Mantel tests performed for each sex separately revealed significant negative correlations between the pairwise relatedness coefficients and the number of days between the capture dates of pairs of wintering Tufted Duck in males and females. This pattern suggests the presence of a small number of co-migrating same-sex sibling pairs in wintering flocks of Tufted Ducks. Our findings provide one of the first genetic analyses of a common duck species outside the breeding season and contribute to the understanding of social interactions in long-distance migratory birds.

Sex identification and PIT-tagging: tools and prospects for studying intersexual differences in freshwater fishes

This study evaluated a technique to allow the long-term monitoring of individual fishes of known sex in the wild using sex confirmation in close proximity to the reproductive period combined with individual tagging. Hundreds of partially migratory roach Rutilus rutilus were tagged with passive integrated transponders (PIT) following sex determination in spring and various performance measures were compared with fish tagged outside the reproductive period in autumn. Short-term survival was > 95% for R. rutilus sexed and tagged under natural field conditions. Total length (LT) did not affect the probability of survival within the size range tagged (119–280mm), nor were there differences in timing of migration the following season between individuals sexed and tagged in spring and individuals tagged in autumn (i.e. outside the reproductive period). Also, a similar per cent of R. rutilus sexed and tagged in spring and tagged in autumn migrated the following season (34·5 and 34·7%). Moreover, long-term recapture data revealed no significant differences in body condition between R. rutilus individuals sexed and tagged in spring, individuals tagged in autumn and unmanipulated individuals. The observed sex ratio of recaptured fish did not differ from the expected values of equal recapture rates between males and females. Hence, there is no observable evidence for an adverse effect of tagging close to the reproductive period and therefore this method is suitable for studying intersexual differences and other phenotypic traits temporarily expressed during reproduction at the individual level in fishes.

Fenología y capacidad de dispersión de Monochamus galloprovincialis (Olivier 1795) en la Península Ibérica = Phenology and dispersal ability of Monochamus galloprovincialis (Olivier 1795) at Iberian Peninsula

La aparición y avance de la enfermedad del marchitamiento del pino (Pine Wilt Desease, PWD), causada por Bursaphelenchus xylophilus (Nematoda; Aphelenchoididae), el nematodo de la madera del pino (NMP), en el suroeste de Europa, ha puesto de manifiesto la necesidad de estudiar la fenología y la dispersión de su único vector conocido en Europa, Monochamus galloprovincialis (Col., Cerambycidae). El análisis de 12 series de emergencias entre 2010 y 2014, registradas en Palencia, València y Teruel, con material procedente de diversos puntos de la península ibérica, demostró una alta variabilidad en la fenología de M. galloprovincialis y la divergencia térmica respecto de las poblaciones portuguesas. Para éstas, el establecimiento de los umbrales térmicos de desarrollo de las larvas post-dormantes del vector (12,2 y 33,5ºC) permitió la predicción de la emergencia mediana para la fecha en la que se acumulaban de 822 grados-día. Ninguna de las series analizadas en este trabajo necesitó de dichos grados-día estimados para la emergencia mediana. Asimismo, la emergencia se adelantó en las regiones más calurosas, mientras que se retrasó en las zonas más templadas. Más allá de la posible variabilidad entre poblaciones locales peninsulares, se detectaron indicios de que la diferencia en la acumulación de calor durante el otoño puede afectar el grado de maduración de las larvas invernantes, y su posterior patrón temporal de emergencia. Por último, también fueron observados comportamientos de protandria en las emergencias. Respecto a la fenología de su vuelo, entre los años 2010 y 2015, fueron ejecutados un total de 8 experimentos de captura de M. galloprovincialis mediante trampas cebadas con atrayentes en diferentes regiones (Castellón, Teruel, Segovia y Alicante) permitiendo el seguimiento del periodo de vuelo. Su análisis permitió constatar la disminución de las capturas y el acortamiento del periodo de vuelo con la altitud, el inicio del vuelo en el mes de mayo/junio a partir de los 14ºC de temperatura media diaria, la influencia de las altas temperaturas en la disminución de las capturas estivales (potencial causante de perfiles bimodales en las curvas de vuelo en las zonas menos frías), la evolución de la proporción de sexos a lo largo del periodo de vuelo (que muestra una mayor captura de hembras al inicio y de machos al final) y el comportamiento diurno y ligado a las altas temperaturas del vuelo circadiano del insecto. Dos redes de muestreo sistemático de insectos saproxílicos instaladas en la Comunitat Valencia (Red MUFFET, 15 parcelas, año 2013) y en Murcia (Red ESFP, 20 parcelas, años 2008-2010) permitieron el estudio de la comunidad de insectos relacionada con M. galloprovincialis. Cada una de las parcelas contaba con una trampa cebada con atrayentes y una estación meteorológica. El registro de más de 250 especies de coleópteros saproxílicos demostró el potencial que tiene el empleo de redes de trampas vigía para la detección temprana de organismos exóticos, además de permitir la caracterización y evaluación de las comunidades de entomofauna útil, representando una de las mejores herramientas de la gestión integrada de plagas. En este caso, la comunidad de saproxílicos estudiada mostró ser muy homogénea respecto a la variación ambiental de las zonas de muestreo, y que pese a las pequeñas variaciones entre las comunidades de los diferentes ecosistemas, el rol que M. galloprovincialis desempeña en ellas a lo largo de todo el gradiente estudiado es el mismo. Con todo, el análisis mediante redes de interacción mostró su relevancia ecológica al actuar de conector entre los diferentes niveles tróficos. Por último, un total de 12 experimentos de marcaje-liberación-recaptura desarrollados entre 2009 y 2012 en Castellón, Teruel, Valencia y Murcia permitieron evaluar el comportamiento dispersivo de M. galloprovincialis. Las detecciones mediante trampas cebadas de los insectos liberados se dieron por lo menos 8 días después de la emergencia. La abundancia de población pareció relacionada con la continuidad, la naturalización de la masa, y con la afección previa de incendios. La dispersión no estuvo influida por la dirección ni la intensidad de los vientos dominantes. La abundancia de material hospedante (en lo referente a las variables de masa y a los índices de competencia) influyó en la captura del insecto en paisajes fragmentados, aunque la ubicación de las trampas optimizó el número de capturas cuando se ubicaron en el límite de la masa y en zonas visibles. Por último también se constató que M. galloprovincialis posee suficiente capacidad de dispersión como para recorrer hasta 1500 m/día, llegando a alcanzar distancias máximas de 13600m o de 22100 m. ABSTRACT The detection and expansion of the Pine Wilt Desease (PWD), caused by Bursaphelenchus xylophilus (Nematoda; Aphelenchoididae), Pine Wood Nematode (PWN), in southwestern Europe since 1999, has triggered off the study of the phenology and the dispersion of its unique vector in the continent, Monochamus galloprovincialis (Coleoptera, Cerambycidae). The analysis of 12 emergence series between 2010 and 2014 registered in Palencia, Teruel and Valencia (Spain), registered from field colonized material collected at several locations of the Iberian Peninsula, showed a high variability in the emergence phenology of M. galloprovincialis. In addition, these patterns showed a very acute thermal divergence regarding a development model fitted earlier in Portugal. Such model forecasted the emergence of 50% of M. galloprovincialis individuals in the Setúbal Peninsula (Portugal) when an average of 822 degree-days (DD) were reached, based on the accumulation of heat from the 1st of March until emergence and lower and upper thresholds of 12.2 ºC and 33,5 °C respectively. In our results, all analyzed series needed less than 822 DD to complete the 50% of the emergence. Also, emergency occurred earlier in the hottest regions, while it was delayed in more temperate areas. Beyond the possible variability between local populations, the difference in the heat accumulation during the fall season may have affected the degree of maturation of overwintering larvae, and subsequently, the temporal pattern of M. galloprovincialis emergences. Therefore these results suggest the need to differentiate local management strategies for the PWN vector, depending on the location, and the climatic variables of each region. Finally, protandrous emergence patterns were observed for M. galloprovincialis in most of the studied data-sets. Regarding the flight phenology of M. galloprovincialis, a total of 8 trapping experiments were carried out in different regions of the Iberian Peninsula (Castellón, Teruel, Segovia and Alicante) between 2010 and 2015. The use of commercial lures and traps allowed monitoring of the flight period of M. galloprovincialis. The analyses of such curves, helped confirming different aspects. First, a decline in the number of catches and a shortening of the flight period was observed as the altitude increased. Flight period was recorded to start in May / June when the daily average temperature went over 14 ° C. A significant influence of high temperatures on the decrease of catches in the summer was found in many occasions, which frequently lead to a bimodal profile of the flight curves in warm areas. The evolution of sex ratio along the flight period shows a greater capture of females at the beginning of the period, and of males at the end. In addition, the circadian response of M. galloprovincialis to lured traps was described for the first time, concluding that the insect is diurnal and that such response is linked to high temperatures. Two networks of systematic sampling of saproxylic insects were installed in the Region of Valencia (Red MUFFET, 15 plots, 2013) and Murcia (Red ICPF, 20 plots, 2008-2010). These networks, intended to serve the double purpose of early-detection and long term monitoring of the saproxylic beetle assemblies, allowed the study of insect communities related to M. galloprovincialis. Each of the plots had a trap baited with attractants and a weather station. The registration of almost 300 species of saproxylic beetles demonstrated the potential use of such trapping networks for the early detection of exotic organisms, while at the same time allows the characterization and evaluation of useful entomological fauna communities, representing one of the best tools for the integrated pest management. In this particular case, the studied community of saproxylic beetles was very homogeneous with respect to environmental variation of the sampling areas, and despite small variations between communities of different ecosystems, the role that M. galloprovincialis apparently plays in them across the studied gradient seems to be the same. However, the analysis through food-webs showed the ecological significance of M. galloprovincialis as a connector between different trophic levels. Finally, 12 mark-release-recapture experiments were carried out between 2009 and 2012 in Castellón, Teruel, Valencia and Murcia (Spain) with the aim to describe the dispersive behavior of M. galloprovincialis as well as the stand and landscape characteristics that could influence its abundance and dispersal. No insects younger than 8 days were caught in lured traps. Population abundance estimates from mark-release-recapture data, seemed related to forest continuity, naturalization, and to prior presence of forest fires. On the other hand, M. galloprovincialis dispersal was not found to be significantly influenced by the direction and intensity of prevailing winds. The abundance of host material, very related to stand characteristics and spacing indexes, influenced the insect abundance in fragmented landscapes. In addition, the location of the traps optimized the number of catches when they were placed in the edge of the forest stands and in visible positions. Finally it was also found that M. galloprovincialis is able to fly up to 1500 m / day, reaching maximum distances of up to 13600 m or 22100 m.

Natal origins of migratory monarch butterflies at wintering colonies in Mexico: New isotopic evidence

Each year, millions of monarch butterflies from eastern North America migrate to overwinter in 10–13 discrete colonies located in the Oyamel forests of central Mexico. For decades efforts to track monarch migration have relied on observations and tag-recapture methods, culminating with the discovery of the wintering colonies in 1975. Monarch tag returns from Mexico, however, are few and primarily from two accessible colonies, and therefore tag-recapture techniques have not quantified natal origins or distinctiveness among monarch populations at wintering sites. Such information would be invaluable in the conservation of the monarch and its migration phenomenon since the wintering sites currently are threatened by habitat alteration. Here we show that stable hydrogen (δD) and carbon (δ13C) isotope ratios of wintering monarchs can be used to evaluate natal origins on the summer breeding range. Stable-hydrogen and carbon isotopic values of 597 wintering monarchs from 13 wintering roost sites were compared with isotopic patterns measured in individuals at natal sites across their breeding range over a single migration cycle. We determined that all monarch wintering colonies were composed of individuals originating mainly from the Midwest, United States, thereby providing evidence for a panmictic model of wintering colony composition. However, two colonies showed more northerly origins, suggesting possible priority colonies for conservation efforts.

Algoritmos recursivos e não-recursivos aplicados à estimação fasorial em sistemas elétricos de potência

Este trabalho apresenta uma análise de algoritmos computacionais aplicados à estimação de fasores elétricos em SEPs. A medição dos fasores é realizada por meio da alocação de Unidades de Medição Fasorial nestes sistemas e encontra diversas aplicações nas áreas de operação, controle, proteção e planejamento. Para que os fasores possam ser aplicados, são definidos padrões de medição, sincronização e comunicação, por meio da norma IEEE C37.118.1. A norma apresenta os padrões de mensagens, timetag, fasores, sistema de sincronização, e define testes para avaliar a estimação. Apesar de abranger todos esses critérios, a diretriz não define um algoritmo de estimação padrão, abrindo espaço para uso de diversos métodos, desde que a precisão seja atendida. Nesse contexto, o presente trabalho analisa alguns algoritmos de estimação de fasores definidos na literatura, avaliando o comportamento deles em determinados casos. Foram considerados, dessa forma, os métodos: Transformada Discreta de Fourier, Método dos Mínimos Quadrados e Transformada Wavelet Discreta, nas versões recursivas e não-recursivas. Esses métodos foram submetidos a sinais sintéticos, a fim de verificar o comportamento diante dos testes propostos pela norma, avaliando o Total Vector Error, tempo de resposta e atraso e overshoot. Os algoritmos também foram embarcados em um hardware, denominado PC104, e avaliados de acordo com os sinais medidos pelo equipamento na saída analógica de um simulador em tempo real (Real Time Digital Simulator).

Estimates of sex- and age-class-specific survival probabilities for a southern Great Barrier Reef green sea turtle population

Sex- and age-class-specific survival probabilities of a southern Great Barrier Reef green sea turtle population were estimated using a capture - mark - recapture (CMR) study and a Cormack - Jolly - Seber (CJS) modelling approach. The CMR history profiles for 954 individual turtles tagged over a 9-year period ( 1984 - 1992) were classified into three age classes ( adult, subadult, juvenile) based on somatic growth and reproductive traits. Reduced-parameter CJS models, accounting for constant survival and time-specific recapture, fitted best for all age classes. There were no significant sex-specific differences in either survival or recapture probabilities for any age class. Mean annual adult survival was estimated at 0.9482 (95% CI: 0.92 - 0.98) and was significantly higher than survival for either subadults or juveniles. Mean annual subadult survival was 0.8474 ( 95% CI: 0.79 - 0.91), which was not significantly different from mean annual juvenile survival estimated at 0.8804 ( 95% CI: 0.84 - 0.93). The time-specific adult recapture probabilities were a function of sampling effort but this was not the case for either juveniles or subadults. The sampling effort effect was accounted for explicitly in the estimation of adult survival and recapture probabilities. These are the first comprehensive sex- and age-class-specific survival and recapture probability estimates for a green sea turtle population derived from a long-term CMR program.

Evaluating trends in abundance of immature green turtles, Chelonia mydas, in the Greater Caribbean

Many long-lived marine species exhibit life history traits. that make them more vulnerable to overexploitation. Accurate population trend analysis is essential for development and assessment of management plans for these species. However, because many of these species disperse over large geographic areas, have life stages inaccessible to human surveyors, and/or undergo complex developmental migrations, data on trends in abundance are often available for only one stage of the population, usually breeding adults. The green turtle (Chelonia mydas) is one of these long-lived species for which population trends are based almost exclusively on either numbers of females that emerge to nest or numbers of nests deposited each year on geographically restricted beaches. In this study, we generated estimates of annual abundance for juvenile green turtles at two foraging grounds in the Bahamas based on long-term capture-mark-recapture (CMR) studies at Union Creek (24 years) and Conception Creek (13 years), using a two-stage approach. First, we estimated recapture probabilities from CMR data using the Cormack-Jolly-Seber models in the software program MARK; second, we estimated annual abundance of green turtles. at both study sites using the recapture probabilities in a Horvitz-Thompson type estimation procedure. Green turtle abundance did not change significantly in Conception Creek, but, in Union Creek, green turtle abundance had successive phases of significant increase, significant decrease, and stability. These changes in abundance resulted from changes in immigration, not survival or emigration. The trends in abundance on the foraging grounds did not conform to the significantly increasing trend for the major nesting population at Tortuguero, Costa Rica. This disparity highlights the challenges of assessing population-wide trends of green turtles and other long-lived species. The best approach for monitoring population trends may be a combination of (1) extensive surveys to provide data for large-scale trends in relative population abundance, and (2) intensive surveys, using CMR techniques, to estimate absolute abundance and evaluate the demographic processes' driving the trends.

The genetic structure of Australasian green turtles (Chelonia mydas): exploring the geographical scale of genetic exchange

Ecological and genetic studies of marine turtles generally support the hypothesis of natal homing, but leave open the question of the geographical scale of genetic exchange and the capacity of turtles to shift breeding sites. Here we combine analyses of mitochondrial DNA (mtDNA) variation and recapture data to assess the geographical scale of individual breeding populations and the distribution of such populations through Australasia. We conducted multiscale assessments of mtDNA variation among 714 samples from 27 green turtle rookeries and of adult female dispersal among nesting sites in eastern Australia. Many of these rookeries are on shelves that were flooded by rising sea levels less than 10 000 years (c. 450 generations) ago. Analyses of sequence variation among the mtDNA control region revealed 25 haplotypes, and their frequency distributions indicated 17 genetically distinct breeding stocks (Management Units) consisting either of individual rookeries or groups of rookeries in general that are separated by more than 500 km. The population structure inferred from mtDNA was consistent with the scale of movements observed in long-term mark-recapture studies of east Australian rookeries. Phylogenetic analysis of the haplotypes revealed five clades with significant partitioning of sequence diversity (Phi = 68.4) between Pacific Ocean and Southeast Asian/Indian Ocean rookeries. Isolation by distance was indicated for rookeries separated by up to 2000 km but explained only 12% of the genetic structure. The emerging general picture is one of dynamic population structure influenced by the capacity of females to relocate among proximal breeding sites, although this may be conditional on large population sizes as existed historically across this region.

Variability in the growth, feeding and condition of barramundi (Lates calcarifer Bloch) in a northern Australian coastal river and impoundment

Lates calcarifer supports important fisheries throughout tropical Australia. Community-driven fish stocking has resulted in the creation of impoundment fisheries and supplemental stocking of selected wild riverine populations. Using predominantly tag-recapture methods, condition assessment and stomach flushing techniques, this study compared the growth of stocked and wild L. calcarifer in a tropical Australian river (Johnstone River) and stocked fish in a nearby impoundment (Lake Tinaroo). Growth of L. calcarifer in the Johnstone River appeared resource-limited, with juvenile fish in its lower freshwater reaches feeding mainly on small aytid shrimp and limited quantities of fish. Growth was probably greatest in estuarine and coastal areas than in the lower freshwater river. Fish in Lake Tinaroo, where prey availability was greater, grew faster than either wild or stocked fish in the lower freshwater areas of the Johnstone River. Growth of L. calcarifer was highly seasonal with marked declines in the cooler months. This was reflected in both stomach fullness and the percentage of fish with empty stomachs but the condition of L. calcarifer was similar across most sites. In areas where food resources appear stretched, adverse effects on resident L. calcarifer populations and their attendant prey species should be minimised through cessation of, or more conservative, stocking practices.

Population estimates and behavioral analyses of managed cat (Felis Catus) colonies located in Miami-Dade County, Florida, parks

The purpose of my study was to collect data on managed cat (Felis catus) colonies located in two Miami-Dade County, Florida, parks, in order to test the following assertions put forward by proponents of the colonies: 1) Managed cat colonies will decline in size over time and 2) The territorial behavior of cats living in established cat colonies will prevent additional cats from joining. I collected observational and photographic capture-recapture data in order to track colony population dynamics. Behavioral data were also collected in order to understand the role that cat behavior plays in influencing colony population dynamics. My results do not support the assertion that colonies will decline over time. Instead, my findings demonstrate that the establishment of colonies on public lands encourages dumping of cats and creates an attractive nuisance. Furthermore, my behavioral analysis suggests that territorial behavior does not play a role in excluding new cats.

Novel insights into the dynamics of green turtle fibropapillomatosis

Outbreaks of fibropapillomatosis (FP), a neoplastic infectious disease of marine turtles, have occurred worldwide since the 1980s. Its most likely aetiological agent is a virus, but disease expression depends on external factors, typically associated with altered environments. The scarcity of robust long-term data on disease prevalence has limited interpretations on the impacts of FP on turtle populations. Here we model the dynamics of FP at 2 green turtle foraging aggregations in Puerto Rico, through 18 yr of capture-mark-recapture data (1997−2014). We observed spatiotemporal variation in FP prevalence, potentially modulated via individual site-fidelity. FP ex pression was residency dependent, and FP-free individuals developed tumours after 1.8 ± 0.8 yr (mean ± SD) in the infected area. Recovery from the disease was likely, with complete tumour regression occurring in 2.7 ± 0.7 yr (mean ± SD). FP does not currently seem to be a major threat to marine turtle populations; however, disease prevalence is yet unknown in many areas. Systematic monitoring is highly advisable as human-induced stressors can lead to deviations in host− pathogen relationships and disease virulence. Finally, data collection should be standardized for a global assessment of FP dynamics and impacts.

Home range, residency and movements of Diplodus sargus and Diplodus vulgaris in a coastal lagoon: Connectivity between nursery and adult habitats

Acoustic telemetry and standard tag-recapture were used to determine the home range and residency of juveniles and sub-adults of Diplodus sargus and Diplodus vulgaris in the Ria Formosa (Portugal) coastal lagoon. Maximum time between recaptures for the standard tag-recapture method was 128 days for D. sargus and 30 days for D. vulgaris. The majority of the fish were recaptured in the vicinity of the tagging location. Fish tagged with acoustic transmitters had a maximum period of time between first and last detections of 62 days for D. sargus and 260 days for D. vulgaris. Minimum convex polygons areas ranged between 148 024 m(2) and 525 930 m(2) for D. sargus and between 23 786 m(2) and 42134 m(2) for D. vulgaris. Both species presented a high residency index between first and last detections. Two D. sargus tagged with acoustic tags were recaptured by fishermen outside the coastal lagoon at distances of 12 km and 90 km from the tagging position, providing evidence that this species leaves the Ria Formosa during the winter time for the adjacent coastal waters. The results of this study reinforce the importance of Ria Formosa as a nursery for D. sargus and D. vulgaris in the south coast of Portugal. (C) 2009 Elsevier Ltd. All rights reserved.