Ictiólogos de la Argentina: Alfredo Salibián

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.

Ictiologos de la Argentina: Gustavo Alfredo Rae

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.

Ictiólogos de la Argentina: Alfredo Fortuny.

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.

Semblanzas Ictiológicas Iberoamericanas: Walter Alfredo Gill Morlis

A través de esta nueva serie tratamos de conocer diferentes aspectos personales de los integrantes de la comunidad ictiológica iberoamericana. Esta iniciativa, comparte el espíritu y objetivo de las semblanzas nacionales buscando informalmente otro punto de unión en la “comunidad de ictiólogos iberoamericanos”. Quizás esté equivocado en mi apreciación, pero creo que vale la pena este intento, ya que, con la colaboración generosa e insoslayable de los integrantes de este “universo”, señalaremos un registro en el tiempo de la Ictiología Neotropical.

Seepage beneath Hoover Dike southern shore of Lake Okeechobee, Florida

Future water needs in southern Florida call for an increase in the storage capacity of Lake Okeechobee. Seepage from the lake is expected to increase as a result of raising the lake level. Data concerning the occurrence and amounts of seepage are needed for the design and operation of flood-control works which will remove excess water from the rich agricultural lands along the southern shore. Intensive studies at five sites along the southern shore of Lake Okeechobee between the Caloosahatchee Canal and the St. Lucie Canal indicate that seepage occurs chiefly through beds of shell and limestone which underlie the Hoover Dike at shallow depth. Seepage rates at the five sites range from about 0.1 to 0.9 cfs per mile per foot of head across the dike. Seepage beneath the 50-mile length of dike should increase from about 22 to 50 cfs if the average stage of the lake is raised from 14 to 16.5 feet. Seepage is greatest between Moore Haven and Clewiston, where deep borrows have been excavated on the landward and lakeward sides of the dike. Most of the seepage from the lake can be controlled by properly spaced toe ditches which would intercept the seepage and return it to the lake. (PDF contains 108 pages.)

Management of northern fur seals on the Pribilof Islands, Alaska, 1786-1981

This paper includes information about the Pribilof Islands since their discovery by Russia in 1786 and the population of northern fur seals, Cailorhinus ursinus, that return there each summer to bear young and to breed. Russia exterminated the native population of sea Oilers, Enhydra lulris, here and nearly subjected the northern fur seal to the same fate before providing proper protection. The northern fur seal was twice more exposed to extinction following the purchase of Alaska and the Pribilof Islands by the United States in 1867. Excessive harvesting was stopped as a result of strict management by the United States of the animals while on land and a treaty between Japan, Russia, Great Britain (for Canada), and the United States that provided needed protection at sea. In 1941, Japan abrogated this treaty which was replaced by a provisional agreement between Canada and the United States that protected the fur seals in the eastern North Pacific Ocean. Japan, the U.S.S.R., Canada, and the United States again insured the survival of these animals with ratification in 1957 of the "Interim Convention on the Conservation of North Pacific Fur Seals," which is still in force. Under the auspices of this Convention, the United States launched an unprecedented manipulation of the resource through controlled removal during 1956-68 of over 300,000 females considered surplus. The biological rationale for the reduction was that production of fewer pups would result in a higher pregnancy rate and increased survival, which would, in turn, produce a sustained annual harvest of 55,000-60,000 males and 10,000-30,000 females. Predicted results did not occur. The herd reduction program instead coincided with the beginning of a decline in the number of males available for harvest. Suspected but unproven causes were changes in the toll normally accounted for by predation, disease, adverse weather, and hookworms. Depletion of the animals' food supply by foreign fishing Heets and the entanglement of fur seals in trawl webbing and other debris discarded at sea became a prime suspect in altering the average annual harvest of males on the Pribilof Islands from 71,500 (1940-56) to 40,000 (1957-59) to 36,000 (1960) to 82,000 (1961) and to 27,347 (1972-81). Thus was born the concept of a research control area for fur seals, which was agreed upon by members of the Convention in 1973 and instituted by the United States on St. George Island beginning in 1974. All commercial harvesting of fur seals was stopped on St. George Island and intensive behavioral studies were begun on the now unharvested population as it responds to the moratorium and attempts to reach its natural ceiling. The results of these and other studies here and on St. Paul Island are expected to eventually permit a comparison between the dynamics of unharvested and harvested populations, which should in turn permit more precise management of fur seals as nations continue to exploit the marine resources of the North Pacific Ocean and Bering Sea. (PDF file contains 32 pages.)

Laboratorio de Ictiofisiología de la Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata

Historia del primer Laboratorio de Ictiofisiología de la Argentina. History of the first Laboratory of Icthyophysiology in Argentina.

Guía para el estudio de macroinvertebrados. II.- Introducción a la metodología de muestreo y análisis de datos.

Sobre la base de los objetivos propuestos, el muestreo tiene que estar cuidadosamente planeado (diseño de protocolo de muestreo) para que se pueda realizar una comprobación estadística de los resultados. Las herramientas de análisis como son los cálculos numéricos y los análisis estadísticos están ligados al estudio en sí, ya que son los que nos permiten demostrar que los resultados de una investigación son el producto de procesos ecológicos y no del azar.

Ictiólogos de la Argentina: Jorge Calvo

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.

Historical Exploitation of the California Sea Lion, Zalophus californianus, in México

The exploitation of California sea lions, Zalophus californianus, in Mexican waters can be divided into four periods as defined by political characteristics of the country: Prehispanic, Colonial, Independent, and Postrevolutionary. During the first period (pre 1533), Native Americans took sea lions at low levels. During the second (1534–1821) and the third (1822–1911) periods, most exploitation was by foreigners and was incidental to other marine mammal harvests. During the Postrevolutionary period (after 1911), sea lions were exploited by Mexican and U.S. citizens for several commercial uses. Exploitation officially ended in 1982, although some small-scale poaching still occurs.

Estudio morfológico y taxonómico de los ampulláridos de la República Argentina: Maria Isabel Hylton Scott. [tomado de la Revista del Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”, Ciencias Zoologicas, Tomo III, nº 5, 1957.]

Corría 1968. Yo era un estudiante enamorado de las ampularias, y alguien me regaló una separata del trabajo de María Isabel Hylton Scott titulado “Estudio morfológico y taxonómico de los ampulláridos de la República Argentina”. Hoy soy un profesor e investigador jubilado, … enamorado de las ampularias ¿Qué pasó en el medio? Por diversas circunstancias de mi vida comencé mi carrera estudiando roedores. Pero como canta un tango, “siempre se vuelve al primer amor” y dos décadas después (hacia 1990) conseguí algo de financiación para estudiar uno de estos extraordinarios animales: Pomacea canaliculata. Esto fue para mí un nuevo comienzo: poco a poco fui dejando mis estudios en ratones silvestres, y formando un grupo dedicado a esta ampularia ¡Fue un cambio de phylum! Pecado difícilmente perdonable en un ambiente científico cada vez más competitivo, pero que me llenó de satisfacción, por lo que me felicito de haberlo cometido. Desde entonces he dirigido a siete doctorandos en distintos aspectos de la morfología y la ecofisiología de este animal (Albrecht, 1998; Vega, 2005; Gamarra-Luques, 2007; Koch, 2008; Giraud-Billoud, 2009; Cueto, 2011; Giraud-Billoud, 2011), y sus tesis tienen al menos dos cosas en común: P. canaliculata casi siempre en el título, y el trabajo de Hylton Scott (1957) siempre citado en la bibliografía. Ella, “la doctora”, la “decana de los zoólogos argentinos” (como escribió Cazzaniga, 1991) fue para nosotros, atrevidos que no la conocimos personalmente, a quien llamábamos por sobrenombre “Doña Marisa”, y lo seguimos haciendo. Lo sigo haciendo yo, porque aunque jubilado “en los papeles”, sigo trabajando detrás de sus pasos. Hoy tengo un doctorando (C. Rodríguez) trabajando en P. canaliculata , el octavo de mis tesistas en esta especie, y deseo que no sea el último. Una revisión de la biología de ampuláridos actualmente en prensa en Malacologia (Hayes et al., 2015) cita repetidas veces el trabajo que hoy reedita ProBiota. Los autores provienen de un amplio “mundo”, porque “el mundo” de los ampuláridos se ha extendido antropocóricamente a lo que hoy es Estados Unidos, Europa, China y Japón. Esto no lo podría haber soñado Doña Marisa cuando comenzó sus pacientes estudios de la embriología de P. canaliculata hace ochenta años (Hylton Scott, 1934). Y si algún cientómetra quisiera calcular la vida media de sus citas, se encontraría con algo sorprendente: que la curva temporal de éstas no va decayendo ¡sino creciendo! Hoy no puedo imaginarme a mí mismo, como investigador, si no me hubiera topado con esa separata de cien páginas, escritas en un castellano elegante y hoy amarillentas, a las que guardo como un tesoro (porque las que usamos son sus fotocopias). Por eso, al acercarse los 25 años de la muerte de esta gran cordobesa (y platense por adopción) le propuse a mi amigo Hugo L. López esta reedición, que el aceptó con entusiasmo. Y también le propuse a mi alumno G. I. Prieto, excelente dibujante, que le diera nueva vida a una vieja foto de Doña Marisa que fue publicada por Cazzaniga (1992). Los que conocieron a “la doctora” personalmente, podrán decir si Prieto logró revivir su penetrante mirada. Creo que sí. Alfredo Castro-Vazquez

La estructura y reproducción de Acanthococcus antarcticus Hooker et Harvey

The present paper gives a full description of the organization of Acanthococcus antarcticus Hooker et Harvey, a not well known member of the Rhodophyllidaceae as well as gives for the first time description of the male and tetrasporic plants. Detailed organization of the carpogonial branches, spermatia and tetraspores is also presented. Nineteen figures illustrate the text (material collected at Deseado port, Santa Cruz prov., Argentina). The following text is the content of the discussion. From the description it is possible to confirm the position of Acanthococcus in the Rhodophyllidaceac as was done by Kylin (Kylin 1960, p. 290 et seg.). It has many similarities in the development of the carpogenic branches and in the formation of spermatia as well in the production of the zonately divided tetrasporangia with the genera of the family whose reproduction is known; Cystoclonium purpureum (Hudson) Batters and Rhodopyllis bifada (Good. et Woodw.) Kützing (Kylin 1923); Calliblepharis jubata (Good. et Woodw.) Kützing (Kylín 1928) and Craspedocarpus erosus (Hook. et Harvey) Sehmitz (Kylin 1932). Apparently the distinguishing feature of Acanthococcus is the structure of the vegetative frond, with the abundant development of rhizoidal filaments in the medula, besides the characteristic appendages of the cystocarps. Harvey's figure (Harvey 1847, P. 181, Fig. 3) of the tranverse section of the plant shows the central portion composed of a dense small-celled medula limited by a region of large cells which is externally covered by a small-celled cortex. As we have seen the small-celled filaments are not restricted to the central portion, but extend into the large-celled portion and can reach the cortex. On the other hand, the eros section of Acanthococcus depicted by Kützing (Kützing 1867, T. 93, Fig. h, under Callophyllis antartica), apparently belongs to another plant, so different in the structure when one compares his figure with Harvey's and the ones in this paper. RESUMEN EN ESPAÑOL Este trabajo presenta una completa descripción de la organización de Acanthococcus antarcticus Hooker et Harvey, un miembro poco conocido de las Rodofilidáceas, así como presenta por primera vez descripciones de las plantas masculinas y de las tetraspóricas. También por primera vez es presentada la organización detallada de las ramas carpogoniales, de los espermecios y de las trásporas. Diecinueve figuras completan el texto (material coleccionado en Puerto Deseado, Prov. Santa Cruz, Argentina).