|Scientific Name:||Aptenodytes forsteri|
|Species Authority:||Gray, 1844|
|Taxonomic Source(s):||del Hoyo, J., Collar, N.J., Christie, D.A., Elliott, A. and Fishpool, L.D.C. 2014. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Lynx Edicions BirdLife International.|
|Red List Category & Criteria:||Near Threatened ver 3.1|
|Reviewer(s):||Butchart, S. & Symes, A.|
|Contributor(s):||Ainley, D., Kooyman, G., Trathan, P. & Woehler, E.|
|Facilitator/Compiler(s):||Butchart, S., Calvert, R., Ekstrom, J., Taylor, J.|
This species has been uplisted to Near Threatened because it is projected to undergo a moderately rapid population decline over the next three generations owing to the effects of projected climate change. However, it should be noted that there is considerable uncertainty over future climatic changes and how these will impact the species.
|Previously published Red List assessments:|
|Range Description:||Aptenodytes forsteri has a circumpolar range, restricted when breeding to the coast of Antarctica where major breeding colonies can be found, amongst other places in the Ross Sea sector, along the coast of Queen Maud Land and Enderby Land (del Hoyo et al. 1992). A survey of satellite images from 2009 found 46 colonies containing c.238,000 breeding pairs, suggesting a total of c.595,000 individuals (Fretwell et al. 2012). This species's breeding colonies are predicted to decline in the northern part of its range by 2025-2052, owing to projected changes in sea ice thickness and extent, as influenced by wind strength and persistence (Ainley et al. 2010, D. Ainley in litt. 2010), although there are considerable uncertainties over this. Jenouvrier et al. (2009) predict a decline in the population viability of the Terre Adelie colony (c.66°S) with increasing frequency of warm events, which are defined by reduced sea ice extent.|
Vagrant:Argentina; Chile; Falkland Islands (Malvinas); French Southern Territories; Heard Island and McDonald Islands; New Zealand; South Georgia and the South Sandwich Islands
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||A survey of satellite images from 2009 has confirmed the presence of 46 colonies containing c.238,000 breeding pairs, suggesting a total of c.595,000 individuals (Fretwell et al. 2012).|
Trend Justification: An analysis carried out by Ainley et al. (2010) suggests that all colonies north of 67-68°S could be lost when Earth's tropospheric temperature reaches 2°C above pre-industrial levels, with negative impacts on all colonies north of 70°S. In this study, 2042 is the median year (range 2025-2052) at which a 2°C warming is forecast to be exceeded by the four climate models used (those models used in the IPCC Fourth Assessment Report [AR4] that most closely predicted data collected on environmental conditions in the Southern Ocean over recent decades) (Ainley et al. 2010). An ensemble of these models was then used to predict changes in climate and habitat in the Southern Ocean until 2025-2052, namely sea ice extent, persistence, concentration and thickness, wind speeds, precipitation and air temperature. Predictions were then made based on historic responses of the species to past variations in environmental conditions (Ainley et al. 2010). According to a survey of satellite images by Fretwell et al. (2012), the global population in 2009 is estimated at c.238,000 breeding pairs, including nine colonies north of 67°S, accounting for c.36,600 pairs. Assuming the loss of these colonies and an exponential population trend, BirdLife International has projected that a decline of c.27% in the number of breeding pairs will occur over the next 61 years (three generations). There are substantial uncertainties over future changes in the patterns of weather variables and how these are likely to impact the species, as well as whether there will be a lag in the decline of mature individuals as recruitment falls, or whether this decline will be proportional to the loss of colonies as climatic changes result in the increased mortality of mature individuals. The relocation of A. forsteri colonies will be limited by decreases in sea ice thickness, making it more difficult for them to find stable, long-lasting fast ice for breeding (Ainley et al. 2010). Colonies could conceivably move to any areas of coastline not affected by ridges formed by wind-blown pack ice; however, where this has occurred in the past it has been regarded as a rare event. Importantly, it has been argued that a simple latitudinal gradient in the loss of sea ice is unlikely, and that warming has so far been regional in the Antarctic (Zwally et al. 2002, Turner et al. 2009, Trathan et al. 2011, Fretwell et al. 2012). With these uncertainties in mind, a precautionary approach is taken, and the population is projected to decline by 20-29% over the next three generations.
|Current Population Trend:||Stable|
|Habitat and Ecology:||This species is marine and pelagic, feeding mainly on fish in Antarctic waters (although krill and cephalopods can be important dietary components in places). It nests almost exclusively on fast ice near the coast or on the coast itself, sometimes up to as much as 200 km from the open sea in large colonies. Only three colonies are known to occur on land (Trathan et al. 2011). It has an annual breeding cycle, arriving at colonies between March and April, with egg-laying between May and June (del Hoyo et al. 1992).|
|Continuing decline in area, extent and/or quality of habitat:||Yes|
|Generation Length (years):||20.4|
|Movement patterns:||Full Migrant|
|Congregatory:||Congregatory (and dispersive)|
|Major Threat(s):||It is thought to be threatened by the effects of projected climate change, primarily through future decreases in sea ice concentration and thickness, as affected by wind speed and persistence, as well as changes in other climatic variables such as precipitation (Ainley et al. 2010, D. Ainley in litt. 2010). Reductions in sea ice thickness are expected to impact the breeding population because of negative effects on the persistence of fast ice, which colonies rely upon through April-December (D. Ainley in litt. 2010). The decline of a colony on Emperor Island from c.150 pairs in c.1970 to fewer than 20 pairs by 1999 (at which time it occurred on land), with the apparent disappearance of the colony by 2009, has been linked to a decline in seasonal sea ice duration (Trathan et al. 2011). Disturbance is a threat in some areas, with problems to colonies caused by the proximity of scientific bases and aircraft movements (del Hoyo et al. 1992).|
Conservation Actions Underway
The species is the subject of on-going international research. Human disturbance is strictly regulated.
Conservation Actions Proposed
Conduct regular surveys to monitor population trends. Continue to improve on existing modelling work to better predict future population changes. Carry out further research into the species's ecology to improve understanding of how environmental changes will affect the population. Continue to carefully monitor the thickness, extent and persistence of Antarctic sea ice, and thus the availability of suitable breeding habitat. Continue international work to tackle the drivers of projected climate change.
|Citation:||BirdLife International. 2012. Aptenodytes forsteri. The IUCN Red List of Threatened Species 2012: e.T22697752A40172193.Downloaded on 04 December 2016.|