Los pinguinos de Magallanes son entre las aves marinas, la especie mas afectada por la contaminac... more Los pinguinos de Magallanes son entre las aves marinas, la especie mas afectada por la contaminacion con petroleo en Chubut y Santa Cruz. Una de las consecuencias adversas de la exposicion a hidrocarburos y otros contaminantes es el aumento de los niveles celulares de especies reactivas del oxigeno o estres oxidativo, considerados herramientas utiles como biomarcadores del impacto de la exposicion a contaminantes quimicos peligrosos. El objetivo de este trabajo fue evaluar parametros hematologicos y marcadores de estres oxidativo durante la rehabilitacion de tres pinguinos empetrolados provenientes del Area Natural Protegida Punta Tombo, Chubut, Argentina. Se tomaron tres muestras de sangre por individuo, la primera muestra al arribo de los pinguinos al centro de rehabilitacion, la segunda una semana despues y una ultima muestra antes de ser liberados. Se obtuvo la cantidad total de leucocitos, la razon heterofilos/linfocitos, el hematocrito y las concentraciones de glucosa y de proteinas totales. Se analizo la actividad de la enzima catalasa, responsable de la degradacion del peroxido de hidrogeno, los niveles de tioles totales no proteicos y el dano a lipidos evaluando las especies reactivas al acido tiobarbiturico, como indicadores de estres oxidativo. El estudio se complemento con la obtencion del peso de los pinguinos. En general, los parametros medidos, aumentaron o se mantuvieron constantes desde la primera tomas toma de muestra hasta la ultima. Si bien algunas de las variables para cada pinguino se comportaron diferentes durante el tratamiento, en general se observo una tendencia a normalizarse hacia el momento de su liberacion. Se concluye que los pinguinos se liberaron en buen estado fisico luego de la rehabilitacion.
El valor de las aves marinas como recurso en la zona costera patagónica se basa en su atractivo p... more El valor de las aves marinas como recurso en la zona costera patagónica se basa en su atractivo para la actividad turística y en menor medida en la producción de guano. Si bien numerosas especies de aves se reproducen en la región, el pingüino de Magallanes constituye el principal atractivo turístico y es la especie de ave que genera el mayor ingreso directo. Las otras especies poseen solamente un valor relativo a nivel local o contribuyen a la diversidad de la fauna silvestre que atrae visitantes nacionales y extranjeros. En cuanto a la explotación guanera, si bien se continúa desarrollando en unas pocas localidades, existen limitaciones que la han convertido en una actividad de baja importancia relativa. Otra actividad relacionada con las aves y que debería ser reconsiderada al planificar el uso sostenible de los recursos en la zona costera es la caza deportiva. Las poblaciones involucradas tienen amplia distribución en ambientes terrestres y acuáticos continentales de la Patagonia. Sin embargo, muchas de ellas habitan o utilizan los ambientes costeros durante parte del año, como el cauquén común (Chloephaga picta), el pato maicero (Anas georgica), el pato barcino (Anas flavirostris, la perdiz chica (Notura maculosa), la martineta común (Eudromia elegans) y la paloma torcaza (Zenaida auriculata). Cabe considerar que no existen hasta la fecha estudios que evalúen los efectos de la actividad sobre las especies, ni las consecuencias de la misma para las poblaciones que utilizan los ambientes costeros. Un aspecto poco tenido en cuenta es la importancia que las aves pueden tener como indicadoras de integridad biológica de algunos ecosistemas. Entre otras cosas, se ha señalado el potencial de las aves marinas para el seguimiento de los niveles de contaminantes que se acumulan a lo largo de la cadena trófica y los stocks de peces comerciales, ya que son sensibles a los cambios en la disponibilidad de alimento. Por otro lado, las aves playeras migratorias están consideradas como buenas indicadoras de la calidad ambiental y el estado de los humedales. Esto sugiere que sería conveniente evaluar la utilidad de algunas especies como indicadoras de cambios ambientales.Fil: Bertellotti, Néstor Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; ArgentinaFil: Yorio, Pablo Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; ArgentinaFil: García Borboroglu, Pablo. Wildlife Conservation Society; Estados Unido
Península Valdés (Patagonia, Argentina) is considered one of the best places in the world to watc... more Península Valdés (Patagonia, Argentina) is considered one of the best places in the world to watch southern right whales (Eubalaena australis) due to the large number of animals as well as to their predictability and proximity to the coast. The present study describes the spatial and temporal dynamics of whalewatching, and the different groups of whales that were the focus of this activity in Península Valdés during six reproductive seasons (from 2005 to 2008 and from 2012 to 2013). The aim was to generate useful tools to improve whalewatching activity in this area. Data were recorded from 1,816 whalewatching trips operated from Puerto Pirámides. Every trip had several stopovers to watch whales, defined as ‘sightings’. At the beginning of the season, most sightings occurred near Puerto Pirámides port, while at the end of the season, sightings were farther from the port. During the first half of the whale season, trips tended to be coastal and shorter but the groups of whales sighted were more varied, including solitary animals, mating groups and mothers with their recently born calves. In the second half of the season, trips tended to be further from the coast and longer, but the whales sighted were mainly mother-calf pairs, the last group of whales to leave the area. This difference in the characteristics of the sightings as the whale season progressed could be the basis to generate different recreational experience opportunities. Whalewatching has a major impact on the regional economy and whalewatching regulations, if correctly applied, could improve the quality of a conservation plan, considering that both gulfs of Península Valdés (San José and Nuevo) are the main calving areas for this species in the South Atlantic Ocean.Fil: Fazio, Ana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Argüelles, María Belén. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Bertellotti, Néstor Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentin
Poxvirus skin disease has been reported in several species of cetaceans, principally in odontocet... more Poxvirus skin disease has been reported in several species of cetaceans, principally in odontocetes, and a single report in mysticetes. Southern right whales Eubalaena australis in Peninsula Valdes, Argentina, show a variety of skin lesions of unknown etiology, and the number of these lesions has increased in recent years. Samples from dead whales were taken in order to establish the etiology of these lesions. One calf and one adult presented ring-type lesions, characterized by a circumscribed and slightly raised area of skin. Lesions were histologically characterized by the presence of microvesicles and vacuolated cells in the stratum spinosum, along with hyperplasia of the stratum corneum and eosinophilic inclusion bodies in the cytoplasm of the epithelial cells. Transmission electron microscopy showed aggregations of virions with typical poxvirus morphology. PCR of cetacean poxvirus (CPV) DNA polymerase, DNA topoisomerase I and parapoxvirus DNA polymerase gene fragments was done,...
Intestinal parasites suppose a cost to hosts as they compete directly for nutritional resources. ... more Intestinal parasites suppose a cost to hosts as they compete directly for nutritional resources. Therefore, hosts must defend themselves against intestinal parasites by mounting an immune response. Many penguin species acquire parasites through their diet and transfer these parasites to their chicks when feeding them. High parasite loads in penguin chicks could have effects on their growth and body condition, and ultimately on their survival. Here, we evaluated the effect of parasites on the cell-mediated immune system in Gentoo penguin (Pygoscelis papua) chicks at Stranger Point (25 de Mayo/King George Island, South Shetland Islands). To this end, 12 chicks were experimentally deparasitized with a mixture of anthelminthic drugs (albendazole and praziquantel), whereas 10 others were kept as control. We measured cutaneous cell-mediated immunity in response to immunization with phytohemagglutinin (PHA). We also analyzed the leukocyte profile in both treated and control groups before and after the treatment. After the treatment, deparasitized birds showed larger foot-web swelling in response to PHA injection than control birds. Deparasitized penguins also showed lower eosinophil and monocyte counts than controls, whereas heterophils, lymphocytes, and total white blood cell counts did not differ between groups. Our results suggest that Gentoo penguin chicks parasitized with intestinal parasites suffer a cost in terms of reduced cell-mediated immune responses that could ultimately affect their survival.
Península Valdés (Patagonia, Argentina) is considered one of the best places in the world to watc... more Península Valdés (Patagonia, Argentina) is considered one of the best places in the world to watch southern right whales (Eubalaena australis) due to the large number of animals as well as to their predictability and proximity to the coast. The present study describes the spatial and temporal dynamics of whalewatching, and the different groups of whales that were the focus of this activity in Península Valdés during six reproductive seasons (from 2005 to 2008 and from 2012 to 2013). The aim was to generate useful tools to improve whalewatching activity in this area. Data were recorded from 1,816 whalewatching trips operated from Puerto Pirámides. Every trip had several stopovers to watch whales, defined as ‘sightings’. At the beginning of the season, most sightings occurred near Puerto Pirámides port, while at the end of the season, sightings were farther from the port. During the first half of the whale season, trips tended to be coastal and shorter but the groups of whales sighted...
Ecological segregation has been documented between males and females in different populations of ... more Ecological segregation has been documented between males and females in different populations of seabirds. Moreover, foraging behaviour and diet have been associated with markers of oxidative status, and have been suggested to be a driver of sex-biased oxidative costs of reproduction in wild marine vertebrates. Nevertheless, the ecological role of sex driving such associations has been little studied. We, therefore, examined whether foraging habitat ( δ 13 C), trophic level ( δ 15 N), dietary antioxidants (retinol and α-tocopherol) and oxidative status (antioxidant capacity and oxidative damage, ROM) were ecologically segregated by sex in Magellanic penguins ( Spheniscus magellanicus ) breeding in Peninsula Valdés (Argentina) visualizing the isotopic, dietary antioxidant, and oxidative status Bayesian spaces as proxies for ecological niches. Our results suggest that specific sexual segregation by ecological niche partially drives the relation between foraging, dietary antioxidants, and oxidative status. The dietary antioxidant niche showed females with extremely low α-tocopherol levels relative to males, although retinol values seemed to be similar between sexes. Higher trophic levels preys (high δ 15 N) were positively associated with α-tocopherol in males suggesting that their greater dependence on the Argentinian hake (a benthopelagic fish rich in α-tocopherol) led to a higher absorption of specific dietary antioxidants than females. In addition, a positive relation between α-tocopherol and ROMs in males suggested that their benthic foraging was associated with greater oxidative damage, and that higher levels of alpha-tocopherol in benthopelagic fish were not sufficient to prevent higher levels of oxidative damage associated with the consumption of such fish. Overall, sex-biased dietary antioxidant niche linked with sex-specific ecological segregation.
Los pinguinos de Magallanes son entre las aves marinas, la especie mas afectada por la contaminac... more Los pinguinos de Magallanes son entre las aves marinas, la especie mas afectada por la contaminacion con petroleo en Chubut y Santa Cruz. Una de las consecuencias adversas de la exposicion a hidrocarburos y otros contaminantes es el aumento de los niveles celulares de especies reactivas del oxigeno o estres oxidativo, considerados herramientas utiles como biomarcadores del impacto de la exposicion a contaminantes quimicos peligrosos. El objetivo de este trabajo fue evaluar parametros hematologicos y marcadores de estres oxidativo durante la rehabilitacion de tres pinguinos empetrolados provenientes del Area Natural Protegida Punta Tombo, Chubut, Argentina. Se tomaron tres muestras de sangre por individuo, la primera muestra al arribo de los pinguinos al centro de rehabilitacion, la segunda una semana despues y una ultima muestra antes de ser liberados. Se obtuvo la cantidad total de leucocitos, la razon heterofilos/linfocitos, el hematocrito y las concentraciones de glucosa y de proteinas totales. Se analizo la actividad de la enzima catalasa, responsable de la degradacion del peroxido de hidrogeno, los niveles de tioles totales no proteicos y el dano a lipidos evaluando las especies reactivas al acido tiobarbiturico, como indicadores de estres oxidativo. El estudio se complemento con la obtencion del peso de los pinguinos. En general, los parametros medidos, aumentaron o se mantuvieron constantes desde la primera tomas toma de muestra hasta la ultima. Si bien algunas de las variables para cada pinguino se comportaron diferentes durante el tratamiento, en general se observo una tendencia a normalizarse hacia el momento de su liberacion. Se concluye que los pinguinos se liberaron en buen estado fisico luego de la rehabilitacion.
El valor de las aves marinas como recurso en la zona costera patagónica se basa en su atractivo p... more El valor de las aves marinas como recurso en la zona costera patagónica se basa en su atractivo para la actividad turística y en menor medida en la producción de guano. Si bien numerosas especies de aves se reproducen en la región, el pingüino de Magallanes constituye el principal atractivo turístico y es la especie de ave que genera el mayor ingreso directo. Las otras especies poseen solamente un valor relativo a nivel local o contribuyen a la diversidad de la fauna silvestre que atrae visitantes nacionales y extranjeros. En cuanto a la explotación guanera, si bien se continúa desarrollando en unas pocas localidades, existen limitaciones que la han convertido en una actividad de baja importancia relativa. Otra actividad relacionada con las aves y que debería ser reconsiderada al planificar el uso sostenible de los recursos en la zona costera es la caza deportiva. Las poblaciones involucradas tienen amplia distribución en ambientes terrestres y acuáticos continentales de la Patagonia. Sin embargo, muchas de ellas habitan o utilizan los ambientes costeros durante parte del año, como el cauquén común (Chloephaga picta), el pato maicero (Anas georgica), el pato barcino (Anas flavirostris, la perdiz chica (Notura maculosa), la martineta común (Eudromia elegans) y la paloma torcaza (Zenaida auriculata). Cabe considerar que no existen hasta la fecha estudios que evalúen los efectos de la actividad sobre las especies, ni las consecuencias de la misma para las poblaciones que utilizan los ambientes costeros. Un aspecto poco tenido en cuenta es la importancia que las aves pueden tener como indicadoras de integridad biológica de algunos ecosistemas. Entre otras cosas, se ha señalado el potencial de las aves marinas para el seguimiento de los niveles de contaminantes que se acumulan a lo largo de la cadena trófica y los stocks de peces comerciales, ya que son sensibles a los cambios en la disponibilidad de alimento. Por otro lado, las aves playeras migratorias están consideradas como buenas indicadoras de la calidad ambiental y el estado de los humedales. Esto sugiere que sería conveniente evaluar la utilidad de algunas especies como indicadoras de cambios ambientales.Fil: Bertellotti, Néstor Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; ArgentinaFil: Yorio, Pablo Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; ArgentinaFil: García Borboroglu, Pablo. Wildlife Conservation Society; Estados Unido
Península Valdés (Patagonia, Argentina) is considered one of the best places in the world to watc... more Península Valdés (Patagonia, Argentina) is considered one of the best places in the world to watch southern right whales (Eubalaena australis) due to the large number of animals as well as to their predictability and proximity to the coast. The present study describes the spatial and temporal dynamics of whalewatching, and the different groups of whales that were the focus of this activity in Península Valdés during six reproductive seasons (from 2005 to 2008 and from 2012 to 2013). The aim was to generate useful tools to improve whalewatching activity in this area. Data were recorded from 1,816 whalewatching trips operated from Puerto Pirámides. Every trip had several stopovers to watch whales, defined as ‘sightings’. At the beginning of the season, most sightings occurred near Puerto Pirámides port, while at the end of the season, sightings were farther from the port. During the first half of the whale season, trips tended to be coastal and shorter but the groups of whales sighted were more varied, including solitary animals, mating groups and mothers with their recently born calves. In the second half of the season, trips tended to be further from the coast and longer, but the whales sighted were mainly mother-calf pairs, the last group of whales to leave the area. This difference in the characteristics of the sightings as the whale season progressed could be the basis to generate different recreational experience opportunities. Whalewatching has a major impact on the regional economy and whalewatching regulations, if correctly applied, could improve the quality of a conservation plan, considering that both gulfs of Península Valdés (San José and Nuevo) are the main calving areas for this species in the South Atlantic Ocean.Fil: Fazio, Ana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Argüelles, María Belén. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Bertellotti, Néstor Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentin
Poxvirus skin disease has been reported in several species of cetaceans, principally in odontocet... more Poxvirus skin disease has been reported in several species of cetaceans, principally in odontocetes, and a single report in mysticetes. Southern right whales Eubalaena australis in Peninsula Valdes, Argentina, show a variety of skin lesions of unknown etiology, and the number of these lesions has increased in recent years. Samples from dead whales were taken in order to establish the etiology of these lesions. One calf and one adult presented ring-type lesions, characterized by a circumscribed and slightly raised area of skin. Lesions were histologically characterized by the presence of microvesicles and vacuolated cells in the stratum spinosum, along with hyperplasia of the stratum corneum and eosinophilic inclusion bodies in the cytoplasm of the epithelial cells. Transmission electron microscopy showed aggregations of virions with typical poxvirus morphology. PCR of cetacean poxvirus (CPV) DNA polymerase, DNA topoisomerase I and parapoxvirus DNA polymerase gene fragments was done,...
Intestinal parasites suppose a cost to hosts as they compete directly for nutritional resources. ... more Intestinal parasites suppose a cost to hosts as they compete directly for nutritional resources. Therefore, hosts must defend themselves against intestinal parasites by mounting an immune response. Many penguin species acquire parasites through their diet and transfer these parasites to their chicks when feeding them. High parasite loads in penguin chicks could have effects on their growth and body condition, and ultimately on their survival. Here, we evaluated the effect of parasites on the cell-mediated immune system in Gentoo penguin (Pygoscelis papua) chicks at Stranger Point (25 de Mayo/King George Island, South Shetland Islands). To this end, 12 chicks were experimentally deparasitized with a mixture of anthelminthic drugs (albendazole and praziquantel), whereas 10 others were kept as control. We measured cutaneous cell-mediated immunity in response to immunization with phytohemagglutinin (PHA). We also analyzed the leukocyte profile in both treated and control groups before and after the treatment. After the treatment, deparasitized birds showed larger foot-web swelling in response to PHA injection than control birds. Deparasitized penguins also showed lower eosinophil and monocyte counts than controls, whereas heterophils, lymphocytes, and total white blood cell counts did not differ between groups. Our results suggest that Gentoo penguin chicks parasitized with intestinal parasites suffer a cost in terms of reduced cell-mediated immune responses that could ultimately affect their survival.
Península Valdés (Patagonia, Argentina) is considered one of the best places in the world to watc... more Península Valdés (Patagonia, Argentina) is considered one of the best places in the world to watch southern right whales (Eubalaena australis) due to the large number of animals as well as to their predictability and proximity to the coast. The present study describes the spatial and temporal dynamics of whalewatching, and the different groups of whales that were the focus of this activity in Península Valdés during six reproductive seasons (from 2005 to 2008 and from 2012 to 2013). The aim was to generate useful tools to improve whalewatching activity in this area. Data were recorded from 1,816 whalewatching trips operated from Puerto Pirámides. Every trip had several stopovers to watch whales, defined as ‘sightings’. At the beginning of the season, most sightings occurred near Puerto Pirámides port, while at the end of the season, sightings were farther from the port. During the first half of the whale season, trips tended to be coastal and shorter but the groups of whales sighted...
Ecological segregation has been documented between males and females in different populations of ... more Ecological segregation has been documented between males and females in different populations of seabirds. Moreover, foraging behaviour and diet have been associated with markers of oxidative status, and have been suggested to be a driver of sex-biased oxidative costs of reproduction in wild marine vertebrates. Nevertheless, the ecological role of sex driving such associations has been little studied. We, therefore, examined whether foraging habitat ( δ 13 C), trophic level ( δ 15 N), dietary antioxidants (retinol and α-tocopherol) and oxidative status (antioxidant capacity and oxidative damage, ROM) were ecologically segregated by sex in Magellanic penguins ( Spheniscus magellanicus ) breeding in Peninsula Valdés (Argentina) visualizing the isotopic, dietary antioxidant, and oxidative status Bayesian spaces as proxies for ecological niches. Our results suggest that specific sexual segregation by ecological niche partially drives the relation between foraging, dietary antioxidants, and oxidative status. The dietary antioxidant niche showed females with extremely low α-tocopherol levels relative to males, although retinol values seemed to be similar between sexes. Higher trophic levels preys (high δ 15 N) were positively associated with α-tocopherol in males suggesting that their greater dependence on the Argentinian hake (a benthopelagic fish rich in α-tocopherol) led to a higher absorption of specific dietary antioxidants than females. In addition, a positive relation between α-tocopherol and ROMs in males suggested that their benthic foraging was associated with greater oxidative damage, and that higher levels of alpha-tocopherol in benthopelagic fish were not sufficient to prevent higher levels of oxidative damage associated with the consumption of such fish. Overall, sex-biased dietary antioxidant niche linked with sex-specific ecological segregation.
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Papers by Marcelo Bertellotti