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Cimino M.A.,University of Delaware | Fraser W.R.,Polar Oceans Research Group | Irwin A.J.,Mount Allison University | Oliver M.J.,University of Delaware
Global Change Biology | Year: 2013

Pygoscelis penguins are experiencing general population declines in their northernmost range whereas there are reported increases in their southernmost range. These changes are coincident with decadal-scale trends in remote sensed observations of sea ice concentrations (SIC) and sea surface temperatures (SST) during the chick-rearing season (austral summer). Using SIC, SST, and bathymetry, we identified separate chick-rearing niche spaces for the three Pygoscelis penguin species and used a maximum entropy approach (MaxEnt) to spatially and temporally model suitable chick-rearing habitats in the Southern Ocean. For all Pygoscelis penguin species, the MaxEnt models predict significant changes in the locations of suitable chick-rearing habitats over the period of 1982-2010. In general, chick-rearing habitat suitability at specific colony locations agreed with the corresponding increases or decreases in documented population trends over the same time period. These changes were the most pronounced along the West Antarctic Peninsula where there has been a rapid warming event during at least the last 50 years. © 2013 Blackwell Publishing Ltd.

Schofield O.,Rutgers University | Ducklow H.W.,Ecosystems Center | Martinson D.G.,Columbia University | Meredith M.P.,British Antarctic Survey | And 2 more authors.
Science | Year: 2010

Climate change will alter marine ecosystems; however, the complexity of the food webs, combined with chronic undersampling, constrains efforts to predict their future and to optimally manage and protect marine resources. Sustained observations at the West Antarctic Peninsula show that in this region, rapid environmental change has coincided with shifts in the food web, from its base up to apex predators. New strategies will be required to gain further insight into how the marine climate system has influenced such changes and how it will do so in the future. Robotic networks, satellites, ships, and instruments mounted on animals and ice will collect data needed to improve numerical models that can then be used to study the future of polar ecosystems as climate change progresses. Copyright Science 2010 by the American Association for the Advancement of Science; all rights reserved.

Kahl L.A.,Rutgers University | Schofield O.,Rutgers University | Fraser W.R.,Polar Oceans Research Group
Integrative and Comparative Biology | Year: 2010

Despite their strong dependence on the pelagic environment, seabirds and other top predators in polar marine ecosystems are generally studied during their reproductive phases in terrestrial environments. As a result, a significant portion of their life history is understudied which in turn has led to limited understanding. Recent advances in autonomous underwater vehicle (AUV) technologies have allowed satellite-tagged Adélie penguins to guide AUV surveys of the marine environment at the Palmer Long-Term Ecological Research (LTER) site on the western Antarctic Peninsula. Near real-time data sent via Iridium satellites from the AUVs to a centralized control center thousands of miles away allowed scientists to adapt AUV sampling strategies to meet the changing conditions of the subsurface. Such AUV data revealed the water masses and fine-scale features associated with Adélie penguin foraging trips. During this study, the maximum concentration of chlorophyll was between 30 and 50m deep. Encompassing this peak in the chlorophyll concentration, within the water-column, was a mixture of nutrient-laden Upper Circumpolar Deep (UCDW) and western Antarctic Peninsula winter water (WW). Together, data from the AUV survey and penguin dives reveal that 54 of foraging by Adélie penguins occurs immediately below the chlorophyll maximum. These data demonstrate how bringing together emerging technologies, such as AUVs, with established methods such as the radio-tagging of penguins can provide powerful tools for monitoring and hypothesis testing of previously inaccessible ecological processes. Ocean and atmosphere temperatures are expected to continue increasing along the western Antarctic Peninsula, which will undoubtedly affect regional marine ecosystems. New and emerging technologies such as unmanned underwater vehicles and individually mounted satellite tracking devices will provide the tools critical to documenting and understanding the widespread ecological change expected in polar regions. © The Author 2010. Published oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved.

Agency: NSF | Branch: Standard Grant | Program: | Phase: ANTARCTIC ORGANISMS & ECOSYST | Award Amount: 333.98K | Year: 2013

The application of innovative ocean observing and animal telemetry technology over Palmer Deep (Western Antarctic Peninsula; WAP) is leading to new understanding, and also to many new questions related to polar ecosystem processes and their control by bio-physical interactions in the polar environment. This multi-platform field study will investigate the impact of coastal physical processes (e.g. tides, currents, upwelling events, sea-ice) on Adélie penguin foraging ecology in the vicinity of Palmer Deep, off Anvers Island, WAP. Guided by real-time surface convergence and divergences based on remotely sensed surface current maps derived from a coastal network of High Frequency Radars (HFRs), a multidisciplinary research team will adaptively sample the distribution of phytoplankton and zooplankton, which influence Adélie penguin foraging ecology, to understand how local oceanographic processes structure the ecosystem.

Core educational objectives of this proposal are to increase awareness and
understanding of (i) global climate change, (ii) the unique WAP ecosystem, (iii) innovative methods and technologies used by the researchers, and (iv) careers in ocean sciences, through interactive interviews with scientists, students, and technicians, during the field work. These activities will be directed towards instructional programming for K-16 students and their teachers. Researchers and educators will conduct formative and summative evaluation to improve the educational program and measure its impacts respectively.

Ainley D.,983 University Avenue | Russell J.,University of Arizona | Jenouvrier S.,Woods Hole Oceanographic Institution | Woehler E.,University of Tasmania | And 3 more authors.
Ecological Monographs | Year: 2010

We assess the response of pack ice penguins, Emperor (Aptenodytes forsteri) and Adélie (Pygoscelis adeliae), to habitat variability and, then, by modeling habitat alterations, the qualitative changes to their populations, size and distribution, as Earth's average tropospheric temperature reaches 2°C above preindustrial levels (ca. 1860), the benchmark set by the European Union in efforts to reduce greenhouse gases. First, we assessed models used in the Intergovernmental Panel on Climate Change Fourth Assessment Report (AR4) on penguin performance duplicating existing conditions in the Southern Ocean. We chose four models appropriate for gauging changes to penguin habitat: GFDL-CM2.1, GFDL-CM2.0, MIROC3.2(hi-res), and MRI-CGCM2.3.2a. Second, we analyzed the composited model ENSEMBLE to estimate the point of 2°C warming (2025-2052) and the projected changes to sea ice coverage (extent, persistence, and concentration), sea ice thickness, wind speeds, precipitation, and air temperatures. Third, we considered studies of ancient colonies and sediment cores and some recent modeling, which indicate the (space/time) large/centennialscale penguin response to habitat limits of all ice or no ice. Then we considered results of statistical modeling at the temporal interannual-decadal scale in regard to penguin response over a continuum of rather complex, meso- to large-scale habitat conditions, some of which have opposing and others interacting effects. The ENSEMBLE meso/decadal-scale output projects a marked narrowing of penguins' Zoogeographic range at the 2°C point. Colonies north of 70° S are projected to decrease or disappear: ∼50% of Emperor colonies (40% of breeding population) and ∼75% of Adélie colonies (70% of breeding population), but limited growth might occur south of 73° S. Net change would result largely from positive responses to increase in polynya persistence at high latitudes, overcome by decreases in pack ice cover at lower latitudes and, particularly for Emperors, ice thickness. Adélie Penguins might colonize new breeding habitat where concentrated pack ice diverges and/or disintegrating ice shelves expose coastline. Limiting increase will be decreased persistence of pack ice north of the Antarctic Circle, as this species requires daylight in its wintering areas. Adélies would be affected negatively by increasing snowfall, predicted to increase in certain areas owing to intrusions of warm, moist marine air due to changes in the Polar Jet Stream. © 2010 by the Ecological Society of America.

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