Predation on cephalopods by Pygoscelis papua and Arctocephalus gazelle at south Orkney Islands

The cephalopod diet of the gentoo penguin, Pygoscelis papua and the Ant− arctic fur seal, Arctocephalus gazella was comparatively analyzed at Laurie Island, South Orkney Islands. A total of 125 stomach samples were collected by the water off−loading method from gentoo penguins during the autumns of 1993, 1995 and 1996, and 39 fur seal scats were collected from mid March to April 1988. Cephalopods preyed upon by gentoo penguins were represented by 1974 beaks (1628 lower, 346 upper) which occurred in 50.4% of the samples. Lower beaks identified belonged exclusively to the squid Psychroteuthis glacialis. The mean lower rostral length (LRL) of these beaks was 1.1 mm (range 0.4– 1.8 mm). From the Antarctic fur seal scats 103 beaks (41 lower, 62 upper) were removed from 60.6% of scats which contained prey remains. The cephalopod species identified were Slosarczykovia circumantarctica and P. glacialis which constituted 78.8% and 21.1% in terms of numbers, respectively. The mean lower rostral length for S. circumantarctica was 2.7 mm (range 2.0–3.5 mm), while that of P. glacialis was 1.6 mm (range 1.0–2.5 mm). The foraging behaviour of the two top predators was analyzed and discussed according to the composition and size of their cephalopod prey

Fish prey of Weddell seals, <i>Leptonychotes weddellii</i>, at Hope Bay, Antarctic Peninsula, during the late summer

The study of the feeding habits of Weddell seals, Leptonychotes weddellii, in the area of west Antarctic Peninsula is essential to understand the role they play in the marine food webs, especially considering that this is one of the regions most affected by climate change. With the aim of detecting temporal changes in the fish predation pattern of seals, a total of 217 scats were collected at Hope Bay, during three consecutive summers (2003, 2004 and 2005). The family Nototheniidae comprised over 80% in numbers of fish preyed by seals. The Antarctic silverfish, Pleuragramma antarctica, was, by far, the most frequent and abundant prey species with a mean percentage frequency of occurrence of 48.7% and representing in average 52.1% in numbers of the fish consumed by seals. Other fish species of lesser importance were the nototheniids Trematomus newnesi, Lepidonotothen larseni, Gobionotothen gibberifrons and the channichthyid Chionodraco rastrospinosus. Temporal variation was observed not only in the relative proportions of the different fish prey taxa but also in the sizes of the dominant prey, P. antarctica. Given the high trophic vulnerability of this species to changes in abiotic factors and food web structure and dynamics, a possible influence of El Nino Southern Oscillation events of 2002–2003 and 2004–2005 should not be discarded. Moreover, special attention should be addressed to its population status, distribution and spatial/temporal availability as prey resource of upper trophic level consumers such as L. weddellii which largely depend on P. antarctica.Facultad de Ciencias Naturales y Muse

Aves, Charadriiformes, Scolopacidae, Limosa haemastica (Linnaeus, 1758): first record from South Shetland Islands and Antarctic Peninsula, Antarctica

We report herein the southernmost record of the Hudsonian Godwit (Limosa haemastica), at two localities in the Antarctic: Esperanza/Hope Bay (January 2005) and 25 de Mayo/King George Island (October 2008). On both occasions a pair of specimens with winter plumage was observed

First record of White-rumped Sandpiper (Calidris fuscicollis) at Esperanza/Hope Bay, Antarctica

The White-rumped Sandpiper (Calidris fuscicollis) (Vieillot 1819) is one of the longest migrating birds that breeds in the high Arctic in Alaska and Canada and spends the post-breeding period in South America. This bird is a frequent vagrant visitor of Islas Georgias del Sur/South Georgia and the South Shetland islands. Here we provide the first record for the White-rumped Sandpiper at the Continental Antarctica. The individual was observed the 2 February 2019 at Esperanza/Hope Bay (63° 23′ 56″ S, 56° 59′ 06″ W), the north of the Antarctic Peninsula, in an ice-free rockery close to a melt-water-run-off area. At the moment of the observation, the temperature was above 0 °C and the wind calm. However, strong winds from the north-west and west directions were registered during the last week of January 2019 at Esperanza Station (peak 65 knots) and at the Drake Passage (peak 49 knots) which might explain the presence of the White-rumped Sandpiper individual at Hope Bay. Our report contributes to list the non-native species observed in Antarctica. One plausible explanation could be related to changes in migratory routes of flying birds.Facultad de Ciencias Naturales y Muse

Female scientists from the Museo Argentino de Ciencias Naturales: “The four from Melchior

En el marco del ciclo “Pioneras: las científicas del Museo Argentino de Ciencias Naturales “Bernardino Rivadavia” (Buenos Aires, Argentina)” rendimos homenaje a mujeres que se han destacado en diversas actividades científicas en la Institución. En el año 2019 distinguimos al primer grupo de mujeres científicas argentinas que participaron de una campaña de investigación en la Antártida. Las cuatro biólogas que trabajaron en la Base Melchior durante el verano 1968-1969 fueron Irene María Bernasconi, María Adela Caría, Elena Dolores Martínez Fontes y Carmen Pujals. Presentamos información sobre su viaje a bordo del buque carguero ARA Bahía Aguirre, la expedición al continente blanco y una breve biografía de cada una de ellas.In the context of the tribute cycle “Pioneers: the female scientists of the Museo Argentino de Ciencias Naturales “Bernardino Rivadavia” (Buenos Aires, Argentina)”, we pay homage to different women who have developed scientific activities in the Institution. In 2019 we paid homage to the first group of female scientists from Argentina who participated in a scientific mission to Antarctica at Melchior Base during the summer of 1968–1969. They were the biologists Irene María Bernasconi, María Adela Caría, Elena Dolores Martínez Fontes, and Carmen Pujals. We present information about their trip on board the ARA Bahía Aguirre ship, their expedition to Antarctica, and their brief biographies.Fil: Ferraro, Daiana Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: de Cabo, Laura Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Libertelli, Marcela Mónica. Ministerio de Relaciones Exteriores, Comercio Interno y Culto. Dirección Nacional del Antártico. Instituto Antártico Argentino; ArgentinaFil: Quartino, Maria Liliana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina. Ministerio de Relaciones Exteriores, Comercio Interno y Culto. Dirección Nacional del Antártico. Instituto Antártico Argentino; ArgentinaFil: Chornogubsky Clerici, Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Tancoff, Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Davies, Yolanda Ester. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Cruz, Laura Edith. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentin

Diet of South Polar Skua chicks in two areas of sympatry with Brown Skua

The food provided to South Polar Skuas (Stercorarius maccormicki) chicks was determined at two Antarctic sites where South Polar Skuas breed sympatrically with Brown Skuas (S. antarcticus). At Harmony Point on Nelson Island, 16 samples of regurgitated stomach contents were analyzed, all contained remains of penguin chicks (mostly soft tissues), which constituted the bulk of the contents, while only two samples had fish or krill remains. These South Polar Skuas had access to penguin colonies, where they hunted chicks or fed on fresh carcasses. However, at Half Moon Island, only two out of nine samples contained minor amounts of penguin remains while fish were the major dietary resource. The high fish content in their diet may indicate a preference for marine rather than terrestrial resources or be the result of competition with Brown Skuas. The variability in food items evidenced by the differences in regurgitated stomach contents indicates that South Polar Skuas may have a trophic plasticity that allows them to change their feeding habits from one resource to another one according to availability. Such may make them less vulnerable to a reduction in the availability of a particular food item.Fil: Graña Grilli, Maricel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Ministerio de Relaciones Exteriores, Comercio Interno y Culto. Dirección Nacional del Antártico. Instituto Antártico Argentino; ArgentinaFil: Libertelli, Marcela. Ministerio de Relaciones Exteriores, Comercio Interno y Culto. Dirección Nacional del Antártico. Instituto Antártico Argentino; ArgentinaFil: Montalti, Diego. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Zoología de Vertebrados. Sección Ornitología; Argentin

Blood parameters of emperor penguin Aptenodytes forsteri chicks at their northernmost Antarctic colony

The emperor penguin (Aptenodytes forsteri) is one of the penguins most threatened by global warming therefore, it is important to monitor physical condition of individuals, especially in the colonies spread further north where the effect of climate change is greater. Here, we present blood and biochemical markers of the general physical condition related to health, nutrition and immune function of emperor penguin chicks at Cerro Nevado/Snow Hill Island, Antarctica, the northernmost colony of their distribution, during the winter season of 2014. We determined the leukocyte counts, the heterophil / lymphocyte ratio and the concentrations of glucose, cholesterol and triglycerides in emperor penguin chicks. These data constitute the first report in chicks of emperor penguins at this location.Fil: D'amico, Veronica Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Libertelli, Marcela. Ministerio de Relaciones Exteriores, Comercio Interno y Culto. Dirección Nacional del Antártico. Instituto Antártico Argentino; ArgentinaFil: Coria, Néstor Rubén. Ministerio de Relaciones Exteriores, Comercio Interno y Culto. Dirección Nacional del Antártico. Instituto Antártico Argentino; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Bertellotti, Néstor Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentin