Emperor Penguin
They are the largest penguin species in the world. This bird is a rather interesting species from the biological standpoint. They have a streamlined plumage, consisting of shiny, water repellent feathers, which prevent the skin from getting wet. The webbed feet of the animal make swimming much easier. The head is big, neck is short and thick, and tail is wedge-shaped and short. The tiny wings of the penguin resemble flippers by their shape. The blackish-blue head is covered with large white and yellow markings on the ears of the animal. The upper parts are blue-grey while the under parts are white, except with the upper breast, having a pale yellow coloring. Males and females are alike.
Habitat
They occur in the Deep South, distributed along the coastline and throughout the compacted ice of the Antarctic continent. They have a circumpolar distribution in the Antarctic almost exclusively between the 66 and 77 degree south latitudes. It almost always breeds on stable pack ice near the coast and up to 18 km (11 mi) offshore.
Diet
This penguin is a carnivore (piscivore and molluscivore), feeding exclusively upon aquatic animals. Their diet mainly consists of krill and fish, supplemented with squid and crustaceans.
Breeding
They can breed at around three years of age, they generally don't begin breeding for another one to three years. The yearly reproductive cycle begins at the start of the Antarctic winter, in March and April, when all mature emperor penguins travel to colonial nesting areas, often walking
31-75mi inland from the edge of the pack ice. The start of travel appears to be triggered by decreasing day lengths; emperor penguins in captivity have been induced successfully into breeding by using artificial lighting systems mimicking seasonal Antarctic day lengths.
They start courtship in March or April, when the temperature can be as low as −40 °C. A lone male gives an ecstatic display, where it stands still and places its head on its chest before inhaling and giving a courtship call for 1–2 seconds; it then moves around the colony and repeats the call. A male and female then stand face to face, with one extending its head and neck up and the other mirroring it; they both hold this posture for several minutes. Once in pairs, couples waddle around the colony together, with the female usually following the male. Before copulation, one bird bows deeply to its mate, its bill pointed close to the ground, and its mate then does the same.
The female penguin lays one 460–470g egg in May or early June; it is vaguely pear-shaped, pale greenish-white, and measures around 12cm × 8cm. Like those of other penguin species, the shell is relatively thick, which helps minimize risk of breakage.
Population
A survey of satellite images from 2009 found 46 colonies containing 238,000 breeding pairs, suggesting a total of 595,000 individuals. Since then, a further seven colonies have been discovered, bringing the total number to 53. The global population estimate has not yet been updated.
An analysis carried out 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.
Assuming the loss of these colonies and an exponential population trend, BirdLife International has projected that a decline of 27% in the number of breeding pairs will occur over the next three generations (61 years). 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 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. 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. 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.
Threats
The species is threatened by the effects of projected climate change, primarily through ongoing and 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 temperature and precipitation. The decrease of a colony on Emperor Island from 150 pairs in the 1970s 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, particularly in seasonal stable ice suitable for nesting. In recent years, Antarctic sea ice increased in extent, especially in East Antarctica. Increased run-off of fresh water from melting glaciers in West Antarctica and strengthening southerly winds in the Ross Sea region were suggested to decrease sea surface temperatures. Alternatively, increases in the wind strength of westerly winds may increase sea ice extent. However it was indicated that this could be a short-term response only 20 years, and that over the long-term, the effect will still be a decrease in sea ice extent. The Antarctic continues to change, hence so too does Emperor Penguin habitats. In the much longer term, Emperor Penguin habitat is likely to deteriorate to a point where suitable locations occur only in restricted refugia or, in the worst case scenario, may be completely unavailable.
Disturbance is a threat in some areas, with problems to colonies caused by the proximity to scientific bases and aircraft movements. Sites visited by tourists collectively account for a very small percentage of the global population, but the impacts of tourism on breeding penguins remain uncertain. Other human impacts potentially include disturbance from researchers, construction of new science facilities and Antarctic krill fisheries. Fisheries for Antarctic Silverfish Pleuragramma antarcticum could potentially be developed in the future. Harvesting of silverfish and krill could pose a threat, if management does not adequately take into account the needs of species that feed upon these species. Oil spills may also be important at local scales. Protection of habitat at sea is important, with the designation of appropriate protection for transit, foraging and rafting areas at sea.
Conservation
Conservation Actions Underway
The species is the subject of on-going international research, but there are currently no special conservation activities. Human disturbance is strictly regulated in some areas (Antarctic Specially Protected Areas).
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 monitor the thickness, extent and persistence of Antarctic sea ice as well as other environmental variables to assess the availability of suitable breeding habitat. Continue international work to tackle the drivers of projected climate change.