Latitudinal and seasonal egg-size variation of the anchoveta (Engraulis ringens) off the Chilean coast

The anchoveta Engraulis ringens is widely distributed along the eastern South Pacific (from 4° to 42°S; Serra et al., 1979) and it has also supported one of the largest fisheries of the world over the last four decades. However, there are few interpopulation comparisons for either the adult or the younger stages. Reproductive traits, such as fecundity or spawning season length, are known to vary with latitude for some fish species (Blaxter and Hunter, 1982; Conover, 1990; Fleming and Gross, 1990; Castro and Cowen, 1991), and latitudinal trends for some early life history traits, such as egg size and larval growth rates, have been reported for others clupeiforms and other fishes (Blaxter and Hempel, 1963; Ciechomski, 1973; Imai and Tanaka, 1987, Conover 1990, Houde 1989). However, there is no published information on potential latitudinal trends during the adult or the early life history of the anchoveta, even though this type of information may help in understanding recruitment variability, especially during recurring large scale events (such as El Niño or La Niña) that affect the entire species range

Sublethal effect of the toxic dinoflagellate Karlodinium veneficum on early life stages of zebrafish (Danio rerio)

Dinoflagellates of the genus Karlodinium are ichthyotoxic species that produce toxins including karlotoxins and karmitoxins. Karlotoxins show hemolytic and cytotoxic activities and have been associated with fish mortality. This study evaluated the effect of toxins released into the environment of Karlodinium veneficum strain K10 (Ebro Delta, NW Mediterranean) on the early stages of Danio rerio (zebrafish). Extracts of the supernatant of K10 contained the mono-sulfated KmTx-10, KmTx-11, KmTx-12, KmTx-13, and a di-sulfated form of KmTx-10. Total egg mortality was observed for karlotoxin concentration higher than 2.69 μg L−1. For 1.35 μg L−1, 87% of development anomalies were evidenced (all concentrations were expressed as KmTx-2 equivalent). Larvae of 8 days postfertilization exposed to 1.35 µg L−1 presented epithelial damage with 80% of cells in the early apoptotic stage. Our results indicate that supernatants with low concentration of KmTxs produce both lethal and sublethal effects in early fish stages. Moreover, apoptosis was induced at concentrations as low as 0.01 μg L−1. This is of great relevance since detrimental long-term effects due to exposure to low concentrations of these substances could affect wild and cultured fish

La imagen y la narrativa como herramientas para el abordaje psicosocial en escenarios de violencia, Departamentos de Tolima y Caquetá

En el presente documento, se abordan diferentes temáticas teniendo en cuenta la importancia del enfoque narrativo y el camino reflexivo que este ha logrado ampliar desde los diferentes contextos significantes en los procesos terapéuticos o con carácter psicosocial en los escenariosde violencia que se presentan en los sistemas. Tomando como referencia las diferentes técnicas de acción, se puede hablar de lafoto voz o (Photovoice), la cual permite ahondar en una situación problémica desde la exposiciónde diferentes imágenes que pueden generar significados a través del poder metafórico y generarcambios notorios en comunidades completas. Es imprescindible para los profesionales en psicología, el aprender a intervenir enlas diversas situaciones de violencia y los relatos de las victimas con los diferentes métodos de creación de preguntas y estrategias que aporten a la vida de las personas de manera significativa;Es por esto que se trabajara en base a casos de importancia encuadrados en problemáticas de violencia y desplazamientos forzados a causa del conflicto armado y la fuerza pública y grupos al margen de la ley como el Caso Peñas Coloradas, con los cuales se pretende adquirir diferentes fortalezas en la apropiación de conocimientos nuevos. Las diferentes teorías psicológicas como la de White, M (1998) y otros autores dan al presente trabajo académico una contextualización argumentada y con carácter científico elcual hace una invitación a seguir investigando y reflexionar acerca de lo que el conflicto le ocasiona a todo un país.In this document, different topics are addressed, taking into account the importance of the narrative approach and the reflective path that it has managed to expand from the different significant multi-contexts in therapeutic processes or with a psychosocial nature in the scenarios of violence that occur in the systems. Taking the different action techniques as a reference, we can talk about the photo you or (Photovoice), which allows delving into a problematic situation from the exposure of different images that can generate meanings through metaphorical power and generate notorious changes in communities. complete. It is essential for professionals in psychology to learn to intervene in various situations of violence and the stories of the victims with the different methods of creating questions and strategies that contribute to the lives of people in a significant way. will work based on important cases framed in problems of violence and forced displacements due to the public force and groups outside the law SUCH AS THE CASE OF PEÑAS COLORADAS, with which it is intended to acquire different strengths in the appropriation of new knowledge. The different psychological theories such as White, M (1998) and other authors give this academic work an argued and scientific contextualization which invites us to continue investigating and reflecting on what the conflict causes to an entire country

Anormalidades durante el desarrollo embrionario de sardina común, Strangomera bentincki en el ambiente natural

To describe and quantify morphological abnormalities during the embryonic development of Strangomera bentincki an area nearby the Itata River mouth was sampled during the reproductive season 2007. Abnormality levels (3-13 %) were coincident with reported levels for other Clupeids species inhabiting areas with similar environmental characteristics to the area studied. Type and abnormalities prevalence were coincident with those reported for other fish species. Blastopore irregular closing and the embryonic axis twist were the most frequent in the samples. These abnormality types would be caused by errors during the epiboly, which can occur spontaneously, influenced by internal or external factors

Variabilidad espacial y temporal de huevos y larvas de Strangomera bentincki y Engraulis ringens, asociados a la desembocadura del río Itata, Chile

El presente estudio analiza la distribución espacial y variabilidad temporal de huevos y larvas de Strangomera bentincki y Engraulis ringens en los periodos de desove principal y secundario, en la zona adyacente a la desembocadura del río Itata, Chile. La información se obtuvo de 7 cruceros oceanográficos entre 1996 a 2005. Se analizó la abundancia y distribución espacial de huevos y larvas en preflexión para ambas especies y la magnitud de las variaciones en su abundancia. Los resultados mostraron que huevos de ambas especies tienden a concentrarse en la costa. La cobertura espacial de larvas en preflexión es mayor que en huevos, en dirección costa-océano. La distribución de los estadios tempranos de sardina común y anchoveta en la plataforma continental frente a la desembocadura el Río Itata fueron variables inter-anualmente. La variación de abundancia entre años fue mayor para huevos que para larvas en ambas especies siendo mayor en los huevos que en las larvas. Las mayores abundancias de huevos y larvas de anchoveta y sardina común se encontraron en salinidades entre los 32 psu y 34 psu, sin embargo, en ocasiones (año 2005) fue posible observar agrupaciones en salinidades menores (20 a 24 psu) en la zona adyacente a la desembocadura del río Itata. El área inmediatamente adyacente a la desembocadura, sin embargo, presentó bajas abundancias de huevos y larvas de estas especies durante los periodos estudiados.This study assesses the spatial and temporal variations in eggs and larval distributions of Engraulis ringens and Strangomera bentincki during their peak and secondary spawning periods, in the zone adjacent to the Itata River mouth, Chile. The information on abundance and distribution of the early life stages of both fish species was obtained from seven oceanographic cruises performed out between 1996 and 2005. The abundance and distribution of eggs and preflexión larvae of both species and, in order to detect potential variations in abundance was analyzed. Our results showed that eggs of both species tended to aggregate at the coast. The spatial extensions of preflexion larvae were broader than that of eggs of both species, along a coast- to- ocean direction. The distribution of the early life stages of both species over the continental shelf off the Itata River mouth was variable inter-annually. These egg and larval abundances showed significant variations among years and the eggs abundance was higher than of larvae. The highest egg and larval abundances occurred at salinities between 32 psu and 34 psu. However, occasionally it was possible to find aggregations in lower salinities (20-24 psu) in the nearby zone of the Itata river mouth. The area contiguous to the river mouth, however, showed low abundance of egg and larvae during the period studied

Larvae of the sand stargazer Sindoscopus australis and notes on the development of Dactyloscopidae (Perciformes: Blennioidei)

Herrera, Guillermo A., Llanos-Rivera, Alejandra, Landaeta, Mauricio F. (2007): Larvae of the sand stargazer Sindoscopus australis and notes on the development of Dactyloscopidae (Perciformes: Blennioidei). Zootaxa 1401 (1): 63-68, DOI: 10.11646/zootaxa.1401.1.

FIGURE 1 in Larvae of the sand stargazer Sindoscopus australis and notes on the development of Dactyloscopidae (Perciformes: Blennioidei)

FIGURE 1. Larvae of Sindoscopus australis, a) 4.4 mm, preflexion, b) 7.3 mm, preflexion, c) 8.6 mm, flexion, d) 13.2 mm, postflexion, e) 16.0 mm, postflexion.Published as part of <i>Herrera, Guillermo A., Llanos-Rivera, Alejandra & Landaeta, Mauricio F., 2007, Larvae of the sand stargazer Sindoscopus australis and notes on the development of Dactyloscopidae (Perciformes: Blennioidei), pp. 63-68 in Zootaxa 1401 (1)</i> on page 65, DOI: 10.11646/zootaxa.1401.1.4, <a href="http://zenodo.org/record/10087727">http://zenodo.org/record/10087727</a&gt