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Tiger sharks (Galeocerdo cuvier) play an important ecological role as top predators, yet knowledge of their reproductive ecology is scarce. Here, the authors report the first observation of a potential neonate G. cuvier at Cocos Island, a predator-dominated oceanic island in the Eastern Tropical Pacific (ETP). The individual was detected using baited remote underwater video stations (BRUVS). The cameras also detected female individuals potentially pregnant, suggesting that parturition may take place at or near the island. Nonetheless, it is still unclear if the presence of a single neonate is an isolated event or evidence that the species is using the island for reproduction.
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Tiburones , Animales , Femenino , Océanos y MaresRESUMEN
A global survey of coral reefs reveals that overfishing is driving resident shark species toward extinction, causing diversity deficits in reef elasmobranch (shark and ray) assemblages. Our species-level analysis revealed global declines of 60 to 73% for five common resident reef shark species and that individual shark species were not detected at 34 to 47% of surveyed reefs. As reefs become more shark-depleted, rays begin to dominate assemblages. Shark-dominated assemblages persist in wealthy nations with strong governance and in highly protected areas, whereas poverty, weak governance, and a lack of shark management are associated with depauperate assemblages mainly composed of rays. Without action to address these diversity deficits, loss of ecological function and ecosystem services will increasingly affect human communities.
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Conservación de los Recursos Naturales , Arrecifes de Coral , Extinción Biológica , Tiburones , Rajidae , Animales , Humanos , Explotaciones Pesqueras , BiodiversidadRESUMEN
Understanding the link between seamounts and large pelagic species (LPS) may provide important insights for the conservation of these species in open water ecosystems. The seamounts along the Cocos Ridge in the Eastern Tropical Pacific (ETP) ocean are thought to be ecologically important aggregation sites for LPS when moving between Cocos Island (Costa Rica) and Galapagos Islands (Ecuador). However, to date, research efforts to quantify the abundance and distribution patterns of LPS beyond the borders of these two oceanic Marine Protected Areas (MPAs) have been limited. This study used drifting-pelagic baited remote underwater video stations (BRUVS) to investigate the distribution and relative abundance of LPS at Cocos Ridge seamounts. Our drifting-pelagic BRUVS recorded a total of 21 species including elasmobranchs, small and large teleosts, dolphins and one sea turtle; of which four species are currently threatened. Depth of seamount summit was the most significant driver for LPS richness and abundance which were significantly higher at shallow seamounts (< 400 m) compared to deeper ones (> 400m). Distance to nearest MPA was also a significant predictor for LPS abundance, which increased at increasing distances from the nearest MPA. Our results suggest that the Cocos Ridge seamounts, specifically Paramount and West Cocos which had the highest LPS richness and abundance, are important aggregation sites for LPS in the ETP. However, further research is still needed to demonstrate a positive association between LPS and Cocos Ridge seamounts. Our findings showed that drifting pelagic BRUVS are an effective tool to survey LPS in fully pelagic ecosystems of the ETP. This study represents the first step towards the standardization of this technique throughout the region.
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Distribución Animal/fisiología , Biodiversidad , Conservación de los Recursos Naturales , Delfines , Ecosistema , Elasmobranquios , Tortugas , Animales , Costa Rica , Ecuador , Océano PacíficoRESUMEN
Understanding how threatened species are distributed in space and time can have direct applications to conservation planning. However, implementing standardized methods to monitor populations of wide-ranging species is often expensive and challenging. In this study, we used baited remote underwater video stations (BRUVS) to quantify elasmobranch abundance and distribution patterns across a gradient of protection in the Pacific waters of Costa Rica. Our BRUVS survey detected 29 species, which represents 54% of the entire elasmobranch diversity reported to date in shallow waters (< 60 m) of the Pacific of Costa Rica. Our data demonstrated that elasmobranchs benefit from no-take MPAs, yet large predators are relatively uncommon or absent from open-fishing sites. We showed that BRUVS are capable of providing fast and reliable estimates of the distribution and abundance of data-poor elasmobranch species over large spatial and temporal scales, and in doing so, they can provide critical information for detecting population-level changes in response to multiple threats such as overfishing, habitat degradation and climate change. Moreover, given that 66% of the species detected are threatened, a well-designed BRUVS survey may provide crucial population data for assessing the conservation status of elasmobranchs. These efforts led to the establishment of a national monitoring program focused on elasmobranchs and key marine megafauna that could guide monitoring efforts at a regional scale.
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Monitoreo Biológico/métodos , Conservación de los Recursos Naturales/métodos , Peces/crecimiento & desarrollo , Tecnología de Sensores Remotos/métodos , Grabación en Video/métodos , Animales , Biodiversidad , Costa Rica , EcosistemaRESUMEN
No disponible
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Humanos , Apnea Obstructiva del Sueño/complicaciones , Trastornos del Inicio y del Mantenimiento del Sueño/complicaciones , Estudios RetrospectivosRESUMEN
INTRODUCCIÓN. El trastorno alimentario relacionado con el sueño (SRED) se caracteriza por la presencia de arousals nocturnos acompañados de alimentación compulsiva, con nivel de conciencia variable durante los mismos. Con frecuencia el trastorno se acompaña de otras alteraciones del sueño, pero la mayoria de casos publicados no aportan estudios polisomnográficos nocturnos (PSGn). Caso1 Varón de 40 años de edad. Desde los 25 años presenta episodios de levantarse de la cama por la noche para ingerir alimento, recordando el episodio vagamente o sin recordarlo. Refiere antecedentes de sonambulismo personales y familiares. El PSGn muestra la presencia de movimientos periódicos de piernas. Caso 2 Varón de 42 años de edad con historia personal y familiar de sonambulismo. Desde hace varios años presenta episodios de alimentación compulsiva durante la noche que no recuerda al día siguiente. Su PSGn muestra apneas obstructivas relacionadas con la posición del cuerpo. Caso 3 Varón de 40 años con gran cantidad de arousals durante el sueño, durante los que siente la necesidad de comer. Al día siguiente recuerda los episodios. Su PSGn muestra la presencia de escasas apneas. CONCLUSIÓN. El SRED puede estar asociado con otras alteraciones del sueño. Su diagnóstico mediante la ayuda del PSGn y su tratamiento pueden mejorar y hacer que los episodios disminuyan en frecuencia (AU)
INTRODUCTION. Sleep - related eating disorder (SRED) is characterised by arousals from sleep associated with compulsive ingestion of food and subsequent poor memory of the event. SRED is frequently combined with other sleep disorders, but most published reports do not include polysomnografic (PSG) studies. Case 1 Male patient, 40 years old. At age 25 he started getting up every night and eating food with only partial or no recall of the event. He has personal and family history of sleepwalking. His PSG showed the presence of periodic limb movements. Case 2 Male patient, 42 years old with history of sleep walking. Several years ago he started compulsive eating at night without recall of the episode. His PSG showed obstructive sleep apneas related to body position. Case 3 Male patient 40 years old with many arousals from sleep, during which he feels the need to eat. The next day he recalls the episodes. His PSG showed a few obstructive sleep apneas. CONCLUSION. SRED may be associated with other sleep disorders. Their diagnosis by PSG study, and their treatment may improve and decrease the frequency of the events (AU)