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"Emperor penguin Behavior."
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Journeys with emperors : tracking the world's most extreme penguin
\"The 2005 Luc Jacquet documentary March of the Penguins won an Oscar for its depiction of emperor penguins' fifty-kilometer trek over sea ice to their breeding grounds. While such a trek may be common for emperors breeding in colonies around the Antarctic perimeter, it is not the case for the largest colonies in the Ross Sea. To understand emperor penguins here, we must follow them on four critical journeys, each with its own challenges and hazards. In this compelling and accessible book, comparative biologist Jerry Kooyman and writer and fellow Antarctic explorer Jim Mastro offer a detailed explanation of all four journeys. The first person to live in isolation for months to study these remarkable, deep-diving birds, Kooyman presents new stories and scientific descriptions with never-before-seen photographs and videos from the very edge. Kooyman has spent over two decades voyaging to the Antarctic and studying these penguins, and he is known among his fellow researchers at the Scripps Institution of Oceanography as \"the penguin guy.\" With this book, readers will have a chance to explore alongside Kooyman and Mastro-and understand in new ways the lives of these remarkable and supremely adapted birds\"-- Provided by publisher.
Book
Emperor Penguins Colony: a new metaheuristic algorithm for optimization
A metaheuristic is a high-level problem independent algorithmic framework that provides a set of guidelines or strategies to develop heuristic optimization algorithms. Metaheuristic algorithms attempt to find the best solution out of all possible solutions of an optimization problem. A very active area of research is the design of nature-inspired metaheuristics. Nature acts as a source of concepts, mechanisms and principles for designing of artificial computing systems to deal with complex computational problems. In this paper, a new metaheuristic algorithm, inspired by the behavior of emperor penguins which is called Emperor Penguins Colony (EPC), is proposed. This algorithm is controlled by the body heat radiation of the penguins and their spiral-like movement in their colony. The proposed algorithm is compared with eight developed metaheuristic algorithms. Ten benchmark test functions are applied to all algorithms. The results of the experiments to find the optimal result, show that the proposed algorithm is better than other metaheuristic algorithms.
Journal Article
An Emperor Penguin Population Estimate: The First Global, Synoptic Survey of a Species from Space
Our aim was to estimate the population of emperor penguins (Aptenodytes fosteri) using a single synoptic survey. We examined the whole continental coastline of Antarctica using a combination of medium resolution and Very High Resolution (VHR) satellite imagery to identify emperor penguin colony locations. Where colonies were identified, VHR imagery was obtained in the 2009 breeding season. The remotely-sensed images were then analysed using a supervised classification method to separate penguins from snow, shadow and guano. Actual counts of penguins from eleven ground truthing sites were used to convert these classified areas into numbers of penguins using a robust regression algorithm.We found four new colonies and confirmed the location of three previously suspected sites giving a total number of emperor penguin breeding colonies of 46. We estimated the breeding population of emperor penguins at each colony during 2009 and provide a population estimate of ~238,000 breeding pairs (compared with the last previously published count of 135,000-175,000 pairs). Based on published values of the relationship between breeders and non-breeders, this translates to a total population of ~595,000 adult birds.There is a growing consensus in the literature that global and regional emperor penguin populations will be affected by changing climate, a driver thought to be critical to their future survival. However, a complete understanding is severely limited by the lack of detailed knowledge about much of their ecology, and importantly a poor understanding of their total breeding population. To address the second of these issues, our work now provides a comprehensive estimate of the total breeding population that can be used in future population models and will provide a baseline for long-term research.
Journal Article
Penguins and Seals Transport Limiting Nutrients Between Offshore Pelagic and Coastal Regions of Antarctica Under Changing Sea Ice
Large animals such as sea birds and marine mammals can transport limiting nutrients between different regions of the ocean, thereby stimulating and enhancing productivity. In Antarctica this process is influenced by formation and breakup of sea ice and its influence on the feeding behaviour of predators and their prey. We used analyses of bioactive metals (for example, Fe, Co, Mn), macronutrients (for example, N) and stable isotopes (δ¹³C and δ¹⁵N) in the excreta of Adélie (Pygoscelis adeliae) and emperor penguins (Aptenodytes forsteri) as well as Weddell seals (Leptonychotes weddellii) from multiple sites, among multiple years (2012–2014) to resolve how changes in sea ice dynamics, as indicated by MODIS satellite images, were coincident with prey switching and likely changes in nutrient fluxes between the offshore pelagic and coastal zones. We also sampled excreta of the south polar skua (Stercorarius maccormicki), which preys on penguins and scavenges the remains of both penguins and seals. We found strong coincidence of isotopic evidence for prey switching, between euphausiids (Euphausia superba and E. crystallorophias) and pelagic/cryopelagic fishes (for example, Pleuragramma antarcticum) in penguins, and between pelagic/cryopelagic fishes and Antarctic toothfish (Dissostichus mawsoni) in Weddell seals, with changes in sea ice cover among years. Further, prey switching was strongly linked to changes in the concentrations of nutrients (Fe and N) deposited in coastal environments by both penguins and seals. Our findings have important implications for understanding how the roles of large animals in supporting coastal productivity may shift with environmental conditions in polar ecosystems.
Journal Article
Population response of an apex Antarctic consumer to its prey and climate fluctuations
A fundamental endeavor in population ecology is to identify the drivers of population dynamics. A few empirical studies included the effect of prey abundance when investigating simultaneously the effects of density-dependence and climate factors on marine top-predator population dynamics. Our aim was to unravel the mechanisms forcing population dynamics of an apex consumer seabird, the south polar skua, using long-term climatic and population time series of the consumer and its prey in Terre Adélie, Antarctica. Influences of density-dependence, climatic factors, and prey abundance with lag effects were tested on the breeding population dynamics with a Bayesian multi-model inference approach. We evidenced a negative trend in breeding population growth rate when density increased. Lagged effects of sea-ice concentration and air temperature in spring and a contemporary effect of prey resources were supported. Remarkably, results outline a reverse response of the south polar skua and one of its main preys to the same environmental factor (sea-ice concentration), suggesting a strong link between skua and penguin dynamics. The causal mechanisms may involve competition for food and space through territorial behavior as well as local climate and prey availability, which probably operate on breeding parameters (breeding propensity, breeding success, or recruitment) rather than on adult survival. Our results provide new insights on the relative importance of factors forcing the population dynamics of an apex consumer including density-dependence, local climate conditions, and direct and indirect effects of prey abundance.
Journal Article
Improving the Emperor Penguin Optimizer Algorithm through Adapted Weighted Sum Mutation Strategy with Information Vector
The Emperor Penguin Optimizer algorithm (EPO) is a recent addition to population-based metaheuristics. However, it has been observed that the algorithm occasionally gets trapped in local optima, particularly when dealing with multi-modal functions. In this paper, we present a novel modification of the Emperor Penguin Optimizer algorithm, termed the Emperor Penguin Optimizer with Weighted Sum Procedure and Information Vector (EPOWIV). The EPOWIV algorithm combines two techniques, the weighted sum procedure and the information vector. To evaluate the effectiveness of the proposed EPOWIV algorithm, a comprehensive comparative study is conducted. This study includes a comparison with the classical EPO algorithm, the EPO algorithm with the weighted sum procedure only, and the EPO algorithm with the information vector. The comparison is carried out on 21 test optimization problems. The comparative results show superiority of the EPOWIV algorithm over its counterparts. The EPOWIV algorithm consistently exhibits superior optimization performance, effectively overcoming the stagnation issues previously associated with the EPO algorithm. It consistently delivers outstanding solutions across a diverse set of test problems.
Journal Article
Emperor Penguins Breeding on Iceshelves
We describe a new breeding behaviour discovered in emperor penguins; utilizing satellite and aerial-survey observations four emperor penguin breeding colonies have been recorded as existing on ice-shelves. Emperors have previously been considered as a sea-ice obligate species, with 44 of the 46 colonies located on sea-ice (the other two small colonies are on land). Of the colonies found on ice-shelves, two are newly discovered, and these have been recorded on shelves every season that they have been observed, the other two have been recorded both on ice-shelves and sea-ice in different breeding seasons. We conduct two analyses; the first using synthetic aperture radar data to assess why the largest of the four colonies, for which we have most data, locates sometimes on the shelf and sometimes on the sea-ice, and find that in years where the sea-ice forms late, the colony relocates onto the ice-shelf. The second analysis uses a number of environmental variables to test the habitat marginality of all emperor penguin breeding sites. We find that three of the four colonies reported in this study are in the most northerly, warmest conditions where sea-ice is often sub-optimal. The emperor penguin's reliance on sea-ice as a breeding platform coupled with recent concerns over changed sea-ice patterns consequent on regional warming, has led to their designation as \"near threatened\" in the IUCN red list. Current climate models predict that future loss of sea-ice around the Antarctic coastline will negatively impact emperor numbers; recent estimates suggest a halving of the population by 2052. The discovery of this new breeding behaviour at marginal sites could mitigate some of the consequences of sea-ice loss; potential benefits and whether these are permanent or temporary need to be considered and understood before further attempts are made to predict the population trajectory of this iconic species.
Journal Article
Crary bank: a deep foraging habitat for emperor penguins in the western Ross Sea
Although most dives of emperor penguins (Aptenodytes forsteri) are less than 100 m, penguins from the Cape Washington colony regularly perform deep dives > 400 m. To evaluate the significance and location of these deep dives of birds on foraging trips from Cape Washington, we report the satellite tracks of three birds. We also review the frequency of deep dives in the 35 of 42 birds that performed deep dives during seven research seasons over 22 years. Records included 83,314 dives, of which 1418 were > 400 m deep (deepest 552 m). Durations of these deep dives ranged from 7 to 13 min, up to more than twice the aerobic dive limit. Inter-deep-dive-intervals (IDDIs) between most deep dives were 10–20 min. The travel routes of satellite-tagged birds showed that all three spent time over Crary Bank, about 100 km from Cape Washington. Dives > 400 m only occurred over Crary Bank in the two satellite-tracked birds that were also equipped with dive recorders. The depths of the dives were consistent with the distribution of the most common, and energy-dense prey item found in their diet, Pleuragramma antarctica. We conclude that significant food resources are located over Crary Bank, accounting for the deep dives and success of birds from Cape Washington, the second largest, stable colony of emperor penguins known.
Journal Article