Description: Adult and juvenile emperor penguins (Aptenodytes forsteri) were fitted with different type of loggers (GPS, TDR, ARGOS) at Atka Bay colony (Queen Maud Land), Weddell Sea coast, in summer season 2017-2018 & 2018-2019. Capture, handling and deployment techniques are shared through several additional files.

Description: In colonial species, it is often assumed that locations in the center of the colony are of highest quality and provide highest breeding success. We tested this prediction, known as the "central-periphery model," in a King Penguin colony in the subantarctic Crozet Archipelago. Breeding activity and survival of 150 penguins, fitted with transponder tags, were monitored over an entire breeding season. Among these 150 birds, 50 bred on the slope at the upper periphery of the colony, where the rates of predation and parasitism by ticks were high. Fifty birds bred in the center of the colony, where rates of predation and tick parasitism were low, and 50 bred at the lower end of the colony, where the rate of tick parasitism was low but predation and flooding were important risks. We predicted that the center of the colony should provide the safest breeding place and consequently be characterized by the highest breeding success and be used by the highest-quality individuals. Yet we found that penguins breeding in the center of the colony had the same breeding success as those at both peripheral locations. In addition, penguins breeding on the upper slope had a higher survival rate than penguins breeding at the center or bottom of the slope and were likely of higher quality. Our study does not support the central-periphery model and emphasizes the complexity behind the relationships among breeding site, breeding success, and individual quality.

Description: Orientation based on visual cues can be extremely difficult in crowded bird colonies due to the presence of many individuals. We studied king penguins (Aptenodytes patagonicus) that live in dense colonies and are constantly faced with such problems. Our aims were to describe adult penguin homing paths on land and to test whether visual cues are important for their orientation in the colony. We also tested the hypothesis that older penguins should be better able to cope with limited visual cues due to their greater experience. We collected and examined GPS paths of homing penguins. In addition, we analyzed 8 months of penguin arrivals to and departures from the colony using data from an automatic identification system. We found that birds rearing chicks did not minimize their traveling time on land and did not proceed to their young (located in creches) along straight paths. Moreover, breeding birds' arrivals and departures were affected by the time of day and luminosity levels. Our data suggest that king penguins prefer to move in and out of the colony when visual cues are available. Still, they are capable of navigating even in complete darkness, and this ability seems to develop over the years, with older breeding birds more likely to move through the colony at nighttime luminosity levels. This study is the first step in unveiling the mysteries of king penguin orientation on land.

Description: King penguins are sexually monomorphically ornamented seabirds that perform a complex visual and acoustic courtship display. Coloured beak spots and ear patches contain information about the condition and physiological status of adult males and females, but their role as a signal of age has previously only been studied in young birds. Vocalizations have mainly been studied as signals of individuality and not in the context of courtship. We investigate two multicomponent signals in the context of mate choice by analysing beak spot, ear patch, and call parameters of wild king penguins. We explore the relation between those signals and age as well as age-classes (chicks, juveniles, adults). Ornament parameters were weakly correlated to continuous age in males, but not in females, while acoustic parameters were highly correlated to continuous age in both sexes. The calls' fundamental frequency and energy parameters, and all the beak spot parameters reliably classified individuals into their age-class. Since age-class was redundantly encoded in both acoustic and colour parameters, we hypothesize that calls and ornaments function as back-up signals that increase the chance of accurately conveying the age-class of the sender to receivers. King penguins might sequentially analyse age-class signals during courtship, where acoustic signals serve as long-range communication when sender and receiver are out of sight, and ornamentation signals become important at close range. We show the importance of considering bimodal, multicomponent signals when studying complex behaviour and discuss how signalling environment, the species' life-history and mating system influence the evolution of communication signals.

Description: Defining reliable demographic models is essential to understand the threats of ongoing environmental change. Yet, in the most remote and threatened areas, models are often based on the survey of a single population, assuming stationarity and independence in population responses. This is the case for the Emperor penguin Aptenodytes forsteri, a flagship Antarctic species that may be at high risk continent-wide before 2100. Here, using genome-wide data from the whole Antarctic continent, we reveal that this top-predator is organized as one single global population with a shared demography since the late Quaternary. We refute the view of the local population as a relevant demographic unit, and highlight that (i) robust extinction risk estimations are only possible by including dispersal rates and (ii) colony-scaled population size is rather indicative of local stochastic events, whereas the species’ response to global environmental change is likely to follow a shared evolutionary trajectory.

Description: Despite the enormous popularity of penguins, their social behaviour remains poorly understood. Video recordings of penguins and penguin colonies are sporadic, of insufficient resolution and duration, and suffer from camera movements that may be artistically motivated but make them scientifically worthless. Recordings of penguin colonies during the winter months are particularly short in supply. Here we present three different observatories that are able to automatically take time-lapse recording over prolonged time periods under harsh climatic conditions. i) The microbs is a very low cost observatory (~700 US$), capable of recording high-resolution (12 MPix) time-lapse data. It features a water-proof Canon D10 consumer-grade camera that we programmed through a bootable SD-card. The camera is powered by a 40 W solar panel and a 100 Ah 12V battery. The microbs can record up to 32 GB of data (approximately one month at a rate of 1 image/min) before the memory card has to be changed manually. ii) To enable even longer observations at very remote locations where a regular change of the SD-card is not feasible, we designed the Mobile Emperor Penguin Observatory (MEPO). It is equipped with a night vision (b/w) and daylight (color) CCD-sensor. Images are recorded on a solid-state PC with very low energy consumption, or they can be sent via satellite (Inmarsat) that is available on large parts of the Antarctic coast. The observatory is remote-operated through the satellite link to adjust parameters such as image frame rate, to select the images to be sent via satellite or to power the observatory up or down. iii) The Single Penguin Observation & Tracking (SPOT) observatory is used to track the movements of individual penguins over prolonged time periods and count the present number of individual penguins. The observatory consists of a wide-angle (45°) camera and a high-speed (5 images/s) high resolution (11 MPix) camera equipped with a telephoto lens (400-600mm). We deployed several microbs, one MEPO and three SPOT observatory between 2011-13 at Crozet Island, Adelie Land and Atka Bay, respectively, and will present first results.

Description: In polar regions, highly adapted social behavior is crucial for the survival of several species. Prominent examples are the huddling behavior of Emperor Penguins, or the crèche (group) formation of King Penguin chicks. To understand how penguins solve the physical problem of movement in densely packed (jammed) groups, we observed Emperor Penguin huddles and King Penguin fledglings with time-lapse/video imaging, and used individual bird tracking and optical flow methods to analyze their movements. We found that Emperor Penguins overcome jamming by moving periodically in large, coordinated clusters. Every 30 - 60 seconds, all penguins make small steps, which travel as a wave through the entire huddle. Over time, these small movements lead to large-scale reorganization of the huddle. Groups of King Penguin fledglings moved in irregular intervals, often attributable to predator attacks, but the individual penguins in the group also moved collectively in a coordinated fashion to ensure the integrity of the group. Our data show that the dynamics of penguin huddling and group formation is governed by intermittency and approach to kinetic arrest in striking analogy with inert non-equilibrium systems. Basic aspects of this behavior can be reproduced with a simple model of interacting point particles. Individual animals are treated as self-driven agents with situation-dependent behavior, similar to simulations of collective swarm behavior in flocks and herds. Both the spontaneous huddle formation and the observed wave patterns emerge from simple rules that only encompass the interaction between directly neighboring individuals. As an important result, our model demonstrates that a collective movement can be triggered by a forward step of any individual within the dense huddle. It remains an open question, however, why individual penguins in a huddle trigger a movement, and by which mechanism the experimentally observed periodicity of huddle movement (~ 40 seconds) remains stable.