ABSTRACT
RESUMEN Los desechos derivados del proceso de perforación en las plataformas marinas petroleras pueden dejar hasta 200 000 toneladas de residuos de perforación en los ecosistemas marinos. El principal agente contaminante son los lodos de perforación petrolera (LPPs), que son usados para enfriar y lubricar la broca de perforación, además de contrarrestar fuerzas de presión y posibles fugas de hidrocarburos. Se sabe que los LPPs tienen un efecto contaminante y tóxico observándose alteraciones en los ecosistemas y efectos adversos en organismos invertebrados marinos, debidos principalmente a la presencia de barita y trazas de metales pesados. En este trabajo se realizaron experimentos de exposición hiperagudos con mezclas completas de lodos de perforación base agua (WBM) a máximos niveles de concentración en colonias de Hydractinia symbiolongicarpus. Los resultados mostraron cambios significativos (p < 0,001) en la morfología de los pólipos inmediatamente después del contacto con WBM, con un incremento 1,5 veces en el diámetro del pólipo y una retracción en la longitud de los tentáculos del 75 %. Después de la exposición (fase de recuperación), se observó una disminución de biomasa a las 72 h con pérdida del 50 % de los pólipos y una reducción de la mata estolonal cercana al 50 % (p < 0,01). Efectos similares han sido reportados en otras especies de cnidarios, como los corales, donde se observó retracción de pólipos y zonas expuestas de exoesqueleto. La exposición a WBM genera irritación tisular en exposición directa y en casos severos pérdida de biomasa.
ABSTRACT Wastes derived from the drilling process on offshore oil platforms can leave up to 200 000 tons of cuttings in marine ecosystems. The principal pollutants in cuttings are drilling muds (DM). The DM are used to cool and lubricate the drill bit, counteract pressure forces and possible hydrocarbon leaks. DM contaminate the marine environment and have toxic adverse effects upon marine invertebrate organisms, mainly due to the presence of barite and traces of heavy metals. In this research, hyperacute exposure experiments were performed with complete mixtures of water-based drilling muds (WBM) at maximum concentration levels in Hydractinia symbiolongicarpus colonies. Results showed significant changes (p < 0.001) in polyp morphology immediately after contact with WBM, with a 1.5-fold increase in its diameter and a 75 % of retraction in the length of the tentacles. A biomass loss was observed after exposure (recovery phase). Near 50 % of polyps and stolonal mat were bioabsorbed with statistical significance (p < 0.01) at 72 h. Similar effects have been reported in other species of cnidarians, such as corals, where there is retraction of polyps and exoskeleton exposed areas also observed. Exposure to WBM generates tissue irritation and extreme cases loss of biomass.
ABSTRACT
The hydromedusae have an important role in marine trophic webs due to their predatory feeding habits. This is the first study of this group of gelatinous marine zooplankton in a coastal upwelling area of Central America. The composition and abundance variability of hydromedusae were studied during six months in 1999 at four stations in Culebra Bay, Gulf of Papagayo, Pacific coast of Costa Rica (10º37’ N-85º40’ W). A total of 53 species were identified, of which 26 are new records for Costa Rica, 21 are new records for Central America, and eight are new records for the Eastern Tropical Pacific. The more abundant species (more than 30% of the total abundance) were Liriope tetraphylla, Solmundella bitentaculata and Aglaura hemistoma. Six species occurred throughout the sampling period, 10 were present only during the dry season (December-April), and 17 were so during the rainy season (May-November). Significant differences of medusan abundances were found between seasons (dry vs. rainy). Maximum abundance (2.1±4.3ind./m³) was recorded when upwelled deeper water influenced the Bay, as indicated by local higher oxygen concentrations and lower water temperatures. The relatively high species richness of medusae found in Culebra Bay is probably related to factors like the pristine condition of the Bay, the arrival of oceanic species transported by the Equatorial Counter Current (ECC), the eastward shoaling of the Costa Rica Dome, and local currents. Illustrations of the 15 more important species are included to facilitate their identification and foster future work in the region.
Las hidromedusas tienen un papel importante en redes tróficas marinas debido a sus hábitos alimenticios depredadores. Este es el primer estudio de este grupo del zooplancton gelatinoso en un area de afloramiento costero en América Central. Durante seis meses de 1999, se estudió la abundancia de hidromedusas en cuatro estaciones en Bahía Culebra, Golfo de Papagayo, costa Pacífica de Costa Rica (10º 37’N-85º40’W). Se identificó un total de 53 especies de las que 26 son registros nuevos para Costa Rica, 21 son registros nuevos para América Central y 8 son nuevos registros para el Pacífico Oriental Tropical. Las especies más abundantes durante el estudio (con más de 30% de la abundancia total) fueron Liriope tetraphylla, Solmundella bitentaculata y Aglaura hemistoma. Seis especies se presentaron en todos los muestreos, 10 especies se presentaron únicamente durante la época seca y 17 se presentaron únicamente durante la época lluviosa. Se mostraron diferencias significativas entre las épocas lluviosa y seca. La máxima abundancia promedio de hidromedusas (2.1±4.3 ind./m³) fue encontrada durante las fechas que se espera el afloramiento costero, indicado por alta concentración de oxígeno y baja temperatura. La rica composición de especies encontrada en Bahía Culebra puede ser el resultado de varios factores, incluyendo la condición prístina de la bahía, el transporte de especies por la Contra Corriente Nor-Ecuatorial (NECC) y los aportes de origen terrestre. Se incluyen ilustraciones de las 15 especies más importantes para facilitar su identificación y promover estudios futuros en la región.
Subject(s)
Animals , Hydrozoa/classification , Costa Rica , Hydrozoa/anatomy & histology , Population Density , Population Dynamics , Seasons , Seawater/analysis , TemperatureABSTRACT
We report the case of a 42-year old woman who was envenomed by a Portuguese man-o'-war (Physalia physalis). She presented an anomalous reaction manifested by purpuric papules that appeared after the initial phase of envenoming (around 24 hours later), when linear erythematous and edematous papules were observed. Late-onset reactions in accidents involving cnidarians commonly include chronic eruptions and local pigmentation.
Os autores relatam um envenenamento causado por um cnidário, a caravela (Physalia physalis), em uma mulher de 42 anos. A paciente apresentou uma reação incomum manifestada por pápulas purpúricas surgidas após a fase inicial de envenenamento (cerca de 24 horas depois) quando foram observadas pápulas lineares edematosas e eritematosas. As reações tardias nos acidentes por cnidários comumente apresentam erupções recorrentes e pigmentações locais.
Subject(s)
Adult , Animals , Female , Humans , Cnidarian Venoms/poisoning , Hydrozoa , Purpura/etiologyABSTRACT
Demonstra-se lesão dermatológica, em caprichoso formato de coração, característica de ataque por caravela-portuguesa, em banhista do sexo feminino, 21 anos.
It is reported the case of a 21-year-old female bather with a skin lesion, heart-shaped ,characteristic of attack by jellyfish.
Subject(s)
Animals , Female , Humans , Young Adult , Bites and Stings/pathology , Cnidarian Venoms/adverse effects , Hydrozoa , SymbolismABSTRACT
Espécies de hidrozoários atecados coletadas em praias da costa do estado do Ceará foram estudadas. No total foram encontradas nove espécies: Bimeria vestita, Pennaria disticha, Eudendrium caraiuru, Eudendrium carneum, Eudendrium pocaruquarum, Eudendrium sp., Sphaerocoryne sp., Porpita porpita e Coryne sp., todas registradas pela primeira vez para a região.
Species of athecate hydroids collected on beaches of the coast of Ceará State were studied. Nine species were found: Bimeria vestita, Pennaria disticha, Eudendrium caraiuru, Eudendrium carneum, Eudendrium pocaruquarum, Eudendrium sp., Sphaerocoryne sp., Porpita porpita and Coryne sp., all recorded for the first time in the region.