First recorded loss of an emperor penguin colony in the recent period of Antarctic regional warming: implications for other colonies (original) (raw)
Related papers
The emperor penguin - Vulnerable to projected rates of warming and sea ice loss
Biological Conservation, 2019
We argue the need to improve climate change forecasting for ecology, and importantly, how to relate long-term projections to conservation. As an example, we discuss the need for effective management of one species, the emperor penguin, Aptenodytes forsteri. This species is unique amongst birds in that its breeding habit is critically dependent upon seasonal fast ice. Here, we review its vulnerability to ongoing and projected climate change, given that sea ice is susceptible to changes in winds and temperatures. We consider published projections of future emperor penguin population status in response to changing environments. Furthermore, we evaluate the current IUCN Red List status for the species, and recommend that its status be changed to Vulnerable, based on different modelling projections of population decrease of ≥50% over the current century, and the specific traits of the species. We conclude that current conservation measures are inadequate to protect the species under future projected scenarios. Only a reduction in anthropogenic greenhouse gas emissions will reduce threats to the emperor penguin from altered wind regimes, rising temperatures and melting sea ice; until such time, other conservation actions are necessary, including increased spatial protection at breeding sites and foraging locations. The designation of large-scale marine spatial protection across its range would benefit the species, particularly in areas that have a high probability of becoming future climate change refugia. We also recommend that the emperor penguin is listed by the Antarctic Treaty as an Antarctic Specially Protected Species, with development of a species Action Plan.
Ecological Monographs, 2010
We assess the response of pack ice penguins, Emperor (Aptenodytes forsteri) and Ade´lie (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 28C 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 28C 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 28C point. Colonies north of 708 S are projected to decrease or disappear: ;50% of Emperor colonies (40% of breeding population) and ;75% of Ade´lie colonies (70% of breeding population), but limited growth might occur south of 738 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. Ade´lie 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. Ade´lies 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.
Marine Ecology Progress Series, 2001
One of the longest continuing data sets involving a marine organism in the Antarctic is that of annual estimates of breeding population size of Adélie penguins Pygoscelis adeliae at colonies on Ross Island, Ross Sea, 1959 to 1997. The sizes of these colonies have displayed significant interannual variability during the 29-yr period. We hypothesized that changes are related to natural environmental factors; and used path analysis to analyze annual variation in population growth in relation to physical environmental factors during that part of the record with comparable sea-ice satellite imagery from 1973 to 1997. The Ross Sea sector of the Southern Ocean lying north of Ross Island, from 150°E to 130°W, comprised our study area. Annual population growth measured during summer was explained best, and inversely, by the extent of sea-ice in the study area 5 winters earlier, and in some way related to the Southern Oscillation. Analysis of a subset of the sea-ice data from 1979 to 1997 indicated strong correlations to ice conditions in the eastern portion of the study area (174 to 130°W), and virtually no correlations to the western half (150°E to 175°W). This result supported other indirect evidence that the Ross Island penguins winter in the eastern Ross Sea/western Amundsen Sea. A demographic model indicated that variation in survival of juveniles and subadults might account for the observed population variation, and would also explain the 5-yr lag as 5 yr is the average age of recruitment to the summer breeding population. Extensive sea-ice during winter appears to reduce subadult survival, expressed subsequently when these cohorts reach maturation. We hypothesize that extensive (more northerly) sea-ice limits access of penguins to productive waters known to occur south of the southern boundary of the Antarctic Circumpolar Current, with starvation or increased predation disproportionately affecting less-experienced birds. The observed patterns of penguin population change, including those preceding the satellite era, imply that sea-ice extent has changed significantly over recent decades.
Antarctic Science, 2011
The emperor penguin (Aptenodytes forsteri) is highly dependent on sea ice conditions, and future climate change may affect its distribution and numbers. Most studies on the demography and population dynamics of emperor penguins in relation to sea ice characteristics were conducted at a single colony (Pointe Géologie). Several non-exclusive hypotheses have been proposed to explain the dramatic decline of this colony, including changes in sea ice conditions, predation, flipper banding and human disturbance. Here, we report and analyse updated long-term trends in numbers of breeding pairs made at two colonies (Pointe Géologie and Haswell Island) where counts are comparable. Similar changes were observed for both colonies and paralleled changes in sea ice extent. At Pointe Géologie and Haswell Island, populations declined similarly and later growth rates were also similar since the early 1990s for Haswell and early 1980s for Pointe Géologie. The magnitude of the decline was similar between both colonies when numbers of breeding pairs were assessed. This study suggests that a common large-scale environmental factor has probably negatively affected both colonies.
PLoS ONE
There will be winners and losers as climate change alters the habitats of polar organisms. For an Adélie penguin (Pygoscelis adeliae) colony on Beaufort Island (Beaufort), part of a cluster of colonies in the southern Ross Sea, we report a recent population increase in response to increased nesting habitat as glaciers have receded. Emigration rates of birds banded as chicks on Beaufort to colonies on nearby Ross Island decreased after 2005 as available habitat on Beaufort increased, leading to altered dynamics of the metapopulation. Using aerial photography beginning in 1958 and modern satellite imagery, we measured change in area of available nesting habitat and population size of the Beaufort colony. Population size varied with available habitat, and both increased rapidly since the 1990s. In accord with glacial retreat, summer temperatures at nearby McMurdo Station increased by ∼0.50°C per decade since the mid-1980s. Although the Ross Sea is likely to be the last ocean with an in...
Adélie penguins and temperature changes in Antarctica: a long-term view
Integrative Zoology, 2012
During the summer months, Adélie penguins represent the dominant biomass of terrestrial Antarctica. Literally millions of individuals nest in ice-free areas around the coast of the continent. Hence, these modern populations of Adélie penguins have often been championed as an ideal biological indicator of ecological and environmental changes that we currently face. In addition, Adélie penguins show an extraordinary record of sub-fossil remains, dating back to the late Pleistocene. At this time, temperatures were much lower than now. Hence, this species offers unique long-term information, at both the genomic and ecological levels, about how a species has responded to climate change over more than 40 000 years.
2002
The Ade´lie penguin, Pygoscelis adeliae, an important component of the Antarctic marine ecosystem, is closely associated with sea ice. Using data collected by Japanese Antarctic Research Expeditions since the 1960s, we examined trends in breeding populations of this species around Lu¨tzow-Holm Bay. Ten colonies ranging in size from 10 to 2,500 individuals were counted along the Soya Coast. Populations fluctuated synchronously, and overall increased at most colonies, except for two: one located deep inside the bay and another where human disturbance was substantial. Populations tended to increase during, or after, periods of sparse sea ice in summer, a condition that occurred once every decade. An increase in population size also occurred 5 years after a winter of extensive sea ice and after a winter of especially reduced sea ice.