Parent–offspring conflict and transition to crèche phase in Chinstrap Penguins (Pygoscelis antarctica)

Parent–offspring conflict theory predicts that offspring seek to prolong the parental care period, while parents strive to shorten it as much as possible. Transition to the crèche phase in penguins involves changes in the dynamic of parental investment in chicks, and thus may be modulated by interests that benefit parent or offspring. We explored parent–offspring interactions in the Chinstrap Penguin (Pygoscelis antarctica) to understand the influence such interactions would have on transition to crèche phase. We studied the effect of hatching date, nestling age, brood size, and nest location on parent–offspring interactions and the length of the guard phase. All behavioral variables related to nestling demands for parental investment increased as well as parental aggression towards their chicks, with increased nestling age. Brood size showed significant effects on both nestling and parental behavior. Hatching date was negatively correlated with the age at crèche. Consequently, the decision to leave the chicks unguarded seemed to be more based on the condition of adults rather than of the chicks. Given the short time available for breeding in Antarctica and that penguins are long-lived birds with several opportunities to breed, there may be conflicting selective factors between investment in feeding chicks versus extending the period of resource acquisition and storage prior to moult.

A global population assessment of the Chinstrap penguin (Pygoscelis antarctica)

Using satellite imagery, drone imagery, and ground counts, we have assembled the first comprehensive global population assessment of Chinstrap penguins (Pygoscelis antarctica) at 3.42 (95th-percentile CI: [2.98, 4.00]) million breeding pairs across 375 extant colonies. Twenty-three previously known Chinstrap penguin colonies are found to be absent or extirpated. We identify five new colonies, and 21 additional colonies previously unreported and likely missed by previous surveys. Limited or imprecise historical data prohibit our assessment of population change at 35% of all Chinstrap penguin colonies. Of colonies for which a comparison can be made to historical counts in the 1980s, 45% have probably or certainly declined and 18% have probably or certainly increased. Several large colonies in the South Sandwich Islands, where conditions apparently remain favorable for Chinstrap penguins, cannot be assessed against a historical benchmark. Our population assessment provides a detailed baseline for quantifying future changes in Chinstrap penguin abundance, sheds new light on the environmental drivers of Chinstrap penguin population dynamics in Antarctica, and contributes to ongoing monitoring and conservation efforts at a time of climate change and concerns over declining krill abundance in the Southern Ocean.

Dynamics of Numbers and Occurrence of Colonial Species of Birds in the Area of Ukrainian Antarctic Station Akademik Vernadsky

The research covers water area, island archipelagos and coastal line of the Antarctic Peninsula from 65°31ʹ S, 64°25ʹ W in the South to 65°03ʹ S, 63°53ʹ W in the North. There was time gap of 7 years between the researches (2011 and 2018), which allows to define tendencies in development of individual colonies and to make conclusion about success of existence of a given species. The work itself was carried out during the first half of January, that is in the time when the stage of brooding ends and the period of hatching starts. As of 2011, 12 nesting points of gentoo penguin (Pygoscelis papua) with total number of 8,342 pairs were found in the region under investigation. Till 2018, quantity of the colony grew to 14, with total number of 14,105 pairs. For seven years, quantity of nesting points of aelie penguin (Pygoscelis adeliae) almost did not change (4 colonies). Instead, total number of the species decreased somewhat: from 3559 pairsin 2011 to 3295 onesin 2018. Number of chinstrap penguin (Pygoscelis antarctica) in united stable locality for nesting also decreased from 26 pairsin 2011 to19 onesin 2018. Booth Island (65°04ʹ S, 64°02ʹ W) for chinstrap penguins and Green Island (65°19ʹ S, 64°09ʹ W) for gentoo penguins are the southern most points of nesting range of the species. Also, 7 colonies of antarctic shag (Phalacrocorax bransfieldensis) were revealed in the region under investigation. For seven years from 2011 to 2018 total number of the species in the region under investigation grew from 190 pairs to 299, and in most cases the antarctics shag forms settlements jointly with penguins.

Holocene occupation history of pygoscelid penguins at Stranger Point, King George (25 de Mayo) Island, northern Antarctic Peninsula

We report additional fossil evidence for pygoscelid penguins breeding on King George (25 de Mayo) Island, South Shetland Islands, in the Holocene beginning at ~7000 cal. yr BP. This evidence comes from a raised marine beach deposit formerly studied and described as Pingfo I at Stranger Point, Potter Peninsula. We relocated and exposed deposits at this site and recovered additional samples of penguin bones from five stratigraphic beds that are redescribed here. Most of these bones are from juvenile penguins and exhibit little or no wear indicating minimal transport to the beach deposits. Some of the bones are developed enough to be identifiable to Adélie ( Pygoscelis adeliae), Gentoo ( Pygoscelis papua), and Chinstrap ( Pygoscelis antarctica) penguins, indicating that all three species were breeding at Stranger Point from ~7320 to 4865 cal. yr BP. This breeding occupation corresponds with the first warming and deglaciation that occurred in the northern Antarctic Peninsula by this time and ends with the onset of reglaciation of the Peninsula. At least 31 abandoned penguin mounds and ornithogenic soils also were located and sampled at Stranger Point and indicate that the current occupation of this area by all three pygoscelid penguins dates no older than ~535 cal. yr BP. The absence of ornithogenic soils from earlier Holocene breeding was probably due to glacial activity and soil solifluction during periods of warming in the mid to late Holocene.

Persistent organic pollutants and porphyrin levels in excreta of penguin colonies from the Antarctic Peninsula area

ABSTRACTPersistent organic pollutants (POPs) and their effects on Antarctic seabirds by using excreta as a non-destructive biomonitoring tool have received little consideration. Here we determine the levels of polychlorinated biphenyls (PCBs) and some organochlorine pesticides such as dichlorodiphenyltrichloroethanes (DDTs), hexachlorobencene (HCB), heptachlor, and endrin aldehyde in penguin excreta. Animal exposure to these environmental contaminants was determined through porphyrins in penguin droppings. Stool samples of Adélie penguin (Pygoscelis adeliae), chinstrap penguin (Pygoscelis antarctica) and gentoo penguin (Pygoscelis papua) were collected on two locations of the Antarctic Peninsula area: Base O´Higgins (Antarctic Peninsula) and Ardley Island (King George Island). Despite POPs have been banned more than three decades ago, the levels (ng g−1ww) of PCBs (1.45-2.35), DDTs (1.33-1.76), HCB (0.51-1.70), endrin (0.48-0.71) and heptachlor (0.97-2.40) showed that these pollutants are still present in Antarctica. Porphyrin levels in excreta (4.6-6.7 nmol g−1dw) were significantly correlated to POPs, indicating certain chemical exposure on penguin colonies that inhabit the Antarctic Peninsula area. The levels of heptachlor found in penguin guano may be affecting some biota in terrestrial sites next to nesting places. Further studies and better understanding of POPs impact on animal performance in Antarctic biota are recommended.