Spatial and temporal diet variability of Adélie (Pygoscelis adeliae) and Emperor (Aptenodytes forsteri) Penguin: a multi tissue stable isotope analysis

The Ross Sea, Antarctica, supports large populations of Emperor Penguin (Aptenodytes forsteri) and Adélie Penguin (Pygoscelis adeliae), two key meso-predators that occupy high trophic levels. Despite these species are largely studied, little is known about their diet outside the breeding period. In the present study, we investigated the intra-annual diet of Adélie and Emperor Penguins belonging to five colonies in the Ross Sea through the stable isotope analysis of different tissues (feathers and shell membranes), synthetized in different seasons, and guano that indicates recent diet. Penguin samples and prey (krill and fish) were collected during the Antarctic spring–summer. δ13C and δ15N of tissues and guano indicate spatio-temporal variation in the penguin diet. The krill consumption by Adélie Penguins was lowest in winter except in the northernmost colony, where it was always very high. It peaked in spring and remained prevalent in summer. The greatest krill contribution to Emperor Penguin’s diet occurred in summer. The relative krill and fish consumption by both species changed in relation to the prey availability, which is influenced by seasonal sea ice dynamics, and according to the penguin life cycle phases. The results highlight a strong trophic plasticity in the Adélie Penguin, whose dietary variability has been already recognized, and in the Emperor Penguin, which had not previously reported. Our findings can help understand how these species might react to resource variation due to climate change or anthropogenic overexploitation. Furthermore, data provides useful basis for future comparisons in the Ross Sea MPA and for planning conservation actions.

Causes for Ivermectin failure in Aptenodytes Forsteri

Ivermectin is an anti-helminthic drug that works on humans but not on penguins. This short perspective seeks to understand and offers an explanation to why Ivermectin is unsuccessful on penguins (other avian animals, such as eagles, and more), but has succeeded in the human population. The bioinformatics approach can lead to the potential design of novel derivatives that would be exclusively for veterinary use.

Emperor penguins and the First German South Polar Expedition, 1901–1903: The elusive colony in Posadowsky Bay

Members of the First German South Polar Expedition (1901–1903) encountered emperor penguins (Aptenodytes forsteri) near their wintering station in the sea ice of Posadowsky Bay, East Antarctica. The penguins appeared to be generally less of scientific interest, but more of a useful resource. Despite the presence of chicks, the men were uncertain about the existence of a breeding colony, and did not record the position of the penguin aggregation they encountered. In later years, only a few sightings confirmed the existence of a colony, and the last ground visit took place in 1960. Based on satellite imagery, a colony appears to exist even now. This paper examines what impact the expedition may have had on this colony, and whether it still exists.

Capacidad de nado del pingüino fósil: Inkayacu paracasensis Clarke, 2010 (Aves: Spheniscidae), con la tasa metabólica basal o estándar

El objetivo del estudio es calcular la capacidad de nado del pingüino extinto Inkayacu paracasensis en términos de la velocidad máxima de natación estimada, utilizando un método teórico biomecánico (mecánica de fluidos) aplicado a reptiles marinos mesozoicos y cetáceos vivos. A efectos comparativos, este parámetro también se calcula para el pingüino africano de patas negras Spheniscus demersus y el pingüino Emperador Aptenodytes forsteri. Los resultados muestran una velocidad máxima estimada de 2,8-3,4 m/seg, 2,8-3,5 m/seg y 3,0-3,7 m/seg, respectivamente. Las velocidades máximas observadas registradas en estudios con especies en cautiverio y en la naturaleza permiten corroborar los valores calculados para las especies vivas, con un error máximo de alrededor del 10% en el caso de A. forsteri. Por lo tanto, el pingüino Emperador e Inkayacu han desarrollado velocidades similares de natación. Además, se sugiere que la frecuencia del batido de la aleta, longitud de la zancada y fases de deslizamiento habrían sido similares en ambas especie de cuerpo grande, en contraste con las de menor tamaño. También se analiza la influencia del modelo de flujo (número de Reynold) en las tres especies de pingüinos. Se sugiere que la morfología del cráneo de Inkayacu podría ser una ventaja en la locomoción con respecto al pingüino Emperador.

Macroplastic in Seabirds at Mirny, Antarctica

Plastic debris makes up the majority of marine debris around the world, and pollution is a serious threat to marine wildlife. Threats represent two types of biological interactions with plastic: entanglement and ingestion. This paper describes interactions of seabirds with plastic in Mirny and draw the attention of researchers to the existing problem. In 2012/2013 and 2015/2016, year-round observations of the author were carried out at Mirny station and Haswell Islands (area of about 12 km2), east Antarctica. One case of entanglement of a molting adult Adélie penguin (Pygoscelis adeliae) in a fishing line was been identified; in addition to one case of an adult emperor penguin (Aptenodytes forsteri) mistakenly ingesting plastic braided rope and subsequently feeding it as part of a food lump to the chick, and two cases of macroplastics found in pellets of south polar skuas (Catharacta maccormicki). Registrations of entanglement and ingestion of macroplastic by seabirds in Mirny are rare. They signal to us about problem that needs to be included in the monitoring for the health of terrestrial biota of the Haswell archipelago.

Observation of the Emperor penguins Aptenodytes forsteri in the Prince Gustav Channel related with unusual sea-ice decline in north-western Weddell Sea

A pair of juvenile emperor penguins (Aptenodytes forsteri) was observed in the northern coast of James Ross Island, the north-western sector of the Weddell Sea, Antarctica, in January 2017. The penguins originated from the colony located on Snow Hill Island, 120-130 km far from the observation area. Despite the emperor penguin´s ability to migrate over long distances, when they are well-known from different areas in Antarctica, this was the first observation of this species in the north of James Ross Island. In this short paper we discuss the environmental factors which allowed the penguins to reach James Ross Island northern coast, especially significant sea ice variability in this area during last decade.