Ictiólogos de la Argentina: Rogelio Bartolomé López.

Spanish: En esta serie se mencionan a todos aquellos que, a través de sus pequeños o grandes aportes, contribuyeron a la consolidación de la disciplina en nuestro país. El plan general de esta contribución consiste en la elaboración de fichas individuales que contengan una lista de trabajos de los diferentes autores, acompañadas por bibliografía de referencia y, cuando ello fuera posible, por imágenes personales y material adicional. Se tratará de guardar un orden cronológico, pero esto no es excluyente, ya que priorizaremos las sucesivas ediciones al material disponible. Este es otro camino para rescatar y revalorizar a quienes en diversos contextos históricos sentaron las bases de lo que hoy es la ictiología nacional. Considero que este es el comienzo de una obra de mayor magnitud en la que se logre describir una parte importante de la historia de las ciencias naturales de la República Argentina. English: This series will include all those people who, by means of their contributions, great and small, played a part in the consolidation of ichthyology in Argentina. The general plan of this work consists of individual factsheets containing a list of works by each author, along with reference bibliography and, whenever possible, personal pictures and additional material. The datasheets will be published primarily in chronological order, although this is subject to change by the availability of materials for successive editions. This work represents another approach for the recovery and revalorization of those who set the foundations of Argentine ichthyology while in diverse historical circumstances. I expect this to be the beginning of a major work that achieves the description of such a significant part of the history of natural sciences in Argentina. Hugo L. López (Texto en espanol. PDF tiene viente tres paginas.)

Ictiólogos de la Argentina: Atila Esteban Gosztonyi

This series will include all those people who, by means of their contributions, great and small, played a part in the consolidation of ichthyology in Argentina. The general plan of this work consists of individual factsheets containing a list of works by each author, along with reference bibliography and, whenever possible, personal pictures and additional material. The datasheets will be published primarily in chronological order, although this is subject to change by the availability of materials for successive editions. This work represents another approach for the recovery and revalorization of those who set the foundations of Argentine ichthyology while in diverse historical circumstances. I expect this to be the beginning of a major work that achieves the description of such a significant part of the history of natural sciences in Argentina.

Comparative Efficacy of Diquat for Control of Two Members of the Hydrocharitaceae: Elodea and Hydrilla

The submersed plants hydrilla (Hydrilla verticillata (L.f.) Royle) and elodea (Elodea canadensis Rich.) are both members of the Hydrocharitaceae family and cause problems in waterways throughout the world. Diquat (6,7-dihydrodipyrido[1,2-α:2’,1’-c]pyrazinediium dibromide) is a contact herbicide used to control nuisance submersed and floating aquatic macrophytes. There is no readily available information in the literature on the control of elodea under various diquat concentration and exposure times (CET) and other than a study by Van et. al 1987, little on hydrilla. Since CET relationships are critical in controlling submersed plants in areas influenced by water exchange, this study was designed to evaluate the efficacy of diquat on hydrilla and elodea under various CET scenarios. (PDF has 3 pages.)

Spatial and temporal patterns in the bycatch of seabirds in the Argentinian longline fishery

Longline fisheries have grown throughout the world’s oceans for more than 40 years. This type of fisheries has captured high-quality fish (mature individuals rather than unwanted juveniles), has had minimal destructive effects on bottom habitats, and has produced a low bycatch of nontargeted fish (Brothers et al., 1999). Seabirds, however, are hooked accidentally when they swallow or are snagged on the baited hooks set by commercial longline crews (Brothers, 1991; Barnes et al., 1997; Tasker et al., 2000; Belda and Sanchez 2001; Jahncke et al., 2001

A través de la selva [Digitalizado de A través de la Selva, Talleres Gráficos de la Penitenciaría, Buenos Aires, 1937]

Prosiguiendo con la tarea de rescate de documentos realizada por ProBiota, tenemos el privilegio de editar en este número la obra A través de la Selva de Esteban Laureano Maradona. Hablar de esta figura, llamado por los indígenas Piognak que significa ‘Dr. Dios’ en pilagá, es mencionar a un ser humano generoso y solidario entregado totalmente al bien común. Un hombre que, además de su ejercicio profesional, se dedicó a la investigación cientifíca de la vida y cultura de los pueblos originarios, así como de la flora y fauna de la región ,colaborando con las comunidades locales en aspectos económicos, culturales, y sociales. No es nuestra intención realizar una sintesís de su vida ya que lo han realizado otros autores, pero si mencionar que, si bien recibió honores y reconocimientos en su larga vida, su figura no es conocida cabalmente en diversos niveles de la sociedad. Esto es una tarea que se debe llevar adelante desde diferentes frentes y una de las primeras sería,como menciona Wikipedia, la edición de algunos de sus 20 libros que se encuentran sin ser publicados, y esperan que el Congreso de la Nación Argentina cumpla con la resolución de 1994 de editarlos y donarlos a bibliotecas públicas del país, como fue el legado de su autor. Esperemos que los que tienen esta responsabilidad movilicen sus esfuerzos personales e institucionales para cumplir con el deseo de una persona que dio todo lo que podía dar sin esperar nada a cambio.

Spatial and temporal variation in the diet of the California sea lion (Zalophus californianus) in the Gulf of California, Mexico

Between June 1995 and May 1996 seven rookeries in the Gulf of California were visited four times in order to collect scat samples for studying spatial and seasonal variability California sea lion prey. The rookeries studied were San Pedro Mártir, San Esteban, El Rasito, Los Machos, Los Cantiles, Isla Granito, and Isla Lobos. The 1273 scat samples collected yielded 4995 otoliths (95.3%) and 247 (4.7%) cephalopod beaks. Fish were found in 97.4% of scat samples collected, cephalopods in 11.2%, and crustaceans in 12.7%. We identified 92 prey taxa to the species level, 11 to genus level, and 10 to family level, of which the most important were Pacific cutlassfish (Trichiurus lepturus), Pacific sardine (Sardinops caeruleus), plainfin midshipman (Porichthys spp.), myctophid no. 1, northern anchovy (Engraulis mordax), Pacific mackerel (Scomber japonicus), anchoveta (Cetengraulis mysticetus), and jack mackerel (Trachurus symmetricus). Significant differences were found among rookeries in the occurrence of all main prey (P≤0.04), except for myctophid no. 1 (P>0.05). Temporally, significant differences were found in the occurrence of Pacific cutlassfish, Pacific sardine, plainfin midshipman, northern anchovy, and Pacific mackerel (P<0.05), but not in jack mackerel (χ 2=2.94, df=3, P=0.40), myctophid no. 1 (χ 2=1.67, df= 3, P=0.64), or lanternfishes (χ 2=2.08, df=3, P=0.56). Differences were observed in the diet and in trophic diversity among seasons and rookeries. More evident was the variation in diet in relation to availability of Pacific sardine.