Ecologia da ictiofauna de um córrego de cabeceira da bacia do alto rio Paraná, Brasil

Ecological studies were conducted in the ichthyofauna of Cedro, a small headwater stream located in a degraded area of State of São Paulo, Brazil, situated in the upper Paraná River basin. These are the results of two non-consecutive years observations and collections in two biotopes of that stream: a pool and a rapid. The ecological characteristics studied change in space and time. The present richness of species is high (21 species), nine of which are constant, six accessory and six accidental. The diversity is low (0.69 to 2.38), and the numeric predominance, from one to three species, occurred in both biotopes. The most frequent species are Poecilia reticulata (Peters, 1859) (28.1%), Corydoras cf. aeneus (Gill, 1858) (20.3%) and Hypostomus cf. ancistroides (Ihering, 1911) (19.8%). The density ranges from 0.7 to 19.8 specimens/m³. The similarity index indicates high similarity between the ichthyofauna (45.0% to 95.0%) inside the same or contiguous biotopes. The evenness (0.46 to 1.0) is comparable to those found in similar studies carried out in other streams.

Biodiversidade e abundância da ictiofauna associada ao cultivo orgânico de Litopenaeus vannamei (Boone, 1931)

The expansion of shrimp farming has caused a series of environmental impacts, often as a result of lack of planning and adequate management. Organic aquaculture has emerged as an alternative to conventional shrimp farming, and differently, aims at the economical, ecological and farming potential of other organisms, such as fishes, oysters and seaweeds. The present study aimed at evaluating the biological diversity and abundance of the ichthyofauna associated to Litopenaeus vannamei organic culture at PRIMAR farm (Rio Grande do Norte, Brazil). The sampling period consisted of four culture cycles (1, 2, 3, and 4) accomplished in four grow-out ponds (V1, V7, V2, and V4) in 2005. The first two culture cycles were carried out during the rainy season, and the last two cycles, during the dry season. Environmental (temperature, salinity, transparency, and rainfall), biodiversity (diversity and uniformity and abundance indexes) of the ichthyofauna, and shrimp productivity data were collected throughout these four culture cycles. The results obtained for the environmental variables showed that both salinity and transparency oscillated in a significant way (p < 0.001) between culture cycles. In relation to the abundance of the ichthyofauna, fifty four species associated to the organic culture of Litopenaeus vannamei were collected and identified at PRIMAR. For the biodiversity criterion, larger species richness (S = 46) and uniformity (E = 0.59 ± 0.16) were observed during cycles 3 and 4 than in cycles 1 and 2 (S = 41 and E = 0.15 ± 0.12). A positive and significant correlation was obtained for the transparency with diversity and uniformity of fish species between cycles 1 and 2 (wet season) and cycles 3 and 4 (dry season) (p < 0.017 - Shannon Index; p < 0.008 - Pielou Index, respectively). A correlation could not be established between shrimp productivity and fish biomass. However, fish biomass decreased from cycles 1 and 2 to cycles 3 and 4, concomitant with an increase in shrimp productivity, most probably due to a higher (from 58.0% to 71.0%) shrimp survival. Regarding the culture potential of the ichthyofauna, three species (Mugil curema, Mugil liza and Chaetodipterus faber) were identified as potential farming alternatives, either singly or in consortium with Litopenaeus vannamei. A fourth species (Centropomus undecimalis) was indicated as an alternative for single culture or in consortium with other fish species. In conclusion, the large diversity of estuarine fishes associated to Litopenaeus vannamei farming observed at PRIMAR clearly indicated the ecological feasibility for organic aquaculture in northeastern Brazil

Inventário das espécies de peixes da costa do Estado do Rio Grande do Norte e aspectos zoogeográficos da ictiofauna recifal do Oceano Atlântico

We present a checklist of the shores fishes of the coast of the Rio Grande do Norte state. Species were registered through the specimens collection, underwater records, samples in landings of artisanal fleet and by compilation of data from literature and ichthyologic collections, between January 2004 to 2006. A total of 440 species form 2 classes, 25 orders, 106 families and 253 genus were registered. It is believed that due the great increase of the number of species registered, the ichthyofauna of the coast of this state is reasonably known

Ictiofauna como indicadora da qualidade ambiental do Rio Matapi, afluente do Rio Amazonas no Estado do Amapá (Brasil).

2016

A genetic perspective on rapid evolution in cane toads (Rhinella marina)

The process of biological invasion exposes a species to novel pressures, in terms of both the environments it encounters and the evolutionary consequences of range expansion. Several invaders have been shown to exhibit rapid evolutionary changes in response to those pressures, thus providing robust opportunities to clarify the processes at work during rapid phenotypic transitions. The accelerating pace of invasion of cane toads (Rhinella marina) in tropical Australia during its 80-year history has been well characterized at the phenotypic level, including common-garden experiments that demonstrate heritability of several dispersal-relevant traits. Individuals from the invasion front (and their progeny) show distinctive changes in morphology, physiology and behaviour that, in combination, result in far more rapid dispersal than is true of conspecifics from long-colonized areas. The extensive body of work on cane toad ecology enables us to place into context studies of the genetic basis of these traits. Our analyses of differential gene expression from toads from both ends of this invasion-history transect reveal substantial upregulation of many genes, notably those involved in metabolism and cellular repair. Clearly, then, the dramatically rapid phenotypic evolution of cane toads in Australia has been accompanied by substantial shifts in gene expression, suggesting that this system is well suited to investigating the genetic underpinnings of invasiveness.

Lecture by Marina Abramovic, given at Florida International University, March 30, 2007

Marina Abramovic she discusses what it means to be a performance artist drawing from stories from her life, including stories from her childhood. Introduction by Dahlia Morgan.

White-faced storm-petrels Pelagodroma marina predated by gulls as biological monitors of plastic pollution in the pelagic subtropical northeast atlantic

Marine plastic pollution is rapidly growing and is a source of major concern. Seabirds often ingest plastic debris and are increasingly used as biological monitors of plastic pollution. However, virtually no studies have assessed plastics in seabirds in the deep subtropical North Atlantic. We investigated whether remains of white-faced storm-petrels (WFSP) present in gull pellets could be used for biomonitoring. We analysed 263 pellets and 79.0% of these contained plastic debris originating in the digestive tract of WFSP. Pellets with no bird prey did not contain plastics. Most debris were fragments (83.6%) with fewer plastic pellets (8.2%). Light-coloured plastics predominated (71.0%) and the most frequent polymer was HDPE (73.0%). Stable isotopes in toe-nails of WFSP containing many versus no plastics did not differ, indicating no individual specialisation leading to differential plastic ingestion. We suggest WFSP in pellets are highly suitable to monitor the little known pelagic subtropical Northeast Atlantic.

Monitoramento da ictiofauna em uma lavoura de arroz convencional.

2015

Inicios de la Marina Mercante de Chile: 1800-1870

Introducción El tema que he escogido para mi disertación en este Simposio sobre “Historia Marítima del Pacífico”, al que hemos sido convocados por el Centro de Investigaciones Historicas de America Central de la Universidad de Costa Rica y que se realiza el San José entre los días 13 y 15 de febrero del año 2001, tiene relación con algunas figuras de empresarios chilenos que constituyen en autenticos precursores de la actividad naviera privada y del comercion chileno de ultramar, como son los señores Jose Francisco de Urrutia Mendiburu y su sueño frustrado de abrir ruta del intercambio mercantil con las islas filipinas en el siglo XVII; Manuel Maria de Undurraga y Yavar, precursor de la idea de establecer una zona marítima costera de explotación exclusiva para Chile; Nicolas de la Curz y Bahamonde, exitoso comerciante chileno establecido en Cadis, caballero ilustrado y primer Conde de Maule…