White-browed penguin (Liera)

The white-browed penguin (Pygoscelis locutusestus) is a species of penguin, most closely related to the earthly gentoo penguin, Adélie penguin, and chinstrap penguin, that is native to the boreal, alpine, and tundra coastlines and islands of the eastern coasts of Novolaurasia on Liera. The white-browed penguin is descended from an extinct species of Pygoscelis penguin, possibly the Pliocene species Pygoscelis tyreei, that was harvested from Earth to Liera, having found a widespread success on the planet.

White-browed penguins can reach a height of 51 to 90 centimeters (20 to 35 inches), making them the largest living species of Lieran penguin of the Pygoscelis genus. Males have a maximum weight around 8.5 kilograms (19 lbs) just before molting and a minimum weight of about 4.9 kilograms (11 lbs) just before mating. For females, the maximum weight is 8.2 kilograms (18 lbs) just before molting, but their weight drops to as little as 4.5 kilograms (9.9 lbs) when guarding the chicks in the nest. White-browed penguins from the north are on average 700 grams (1.5 lbs) heavier and 10 centimeters (3.9 inches) taller than the southern populations, as a result of a pattern known as Bergmann's Rule (in general, a more massive organism has a smaller surface area-to-volume to retain more heat in the colder environments). The white-browed penguin is easily recognized by the wide, white "cap" across the top of its head and its bright orange bill. It has pale orange, webbed feet and a fairly long tail – one of the most prominent tail of all penguin species. Chicks have grey backs with white fronts. As the white-browed penguin waddles along on land, its tail sticks out behind, sweeping from side to side, hence the scientific name Pygoscelis, which means "rump-tailed".

White-browed penguins mainly live on crustaceans, such as krill and shrimp, with fish and cephalopods making up only about 15% and 10% of the diet respectively. They are, however, opportunistic feeders and around centraleastern Novolaurasian coasts are known to take roughly equal proportions of fish, squid, and octopuses. The white-browed penguins' diet is high in salt, as they eat organisms with relatively the same salinity as sea water, which can lead to complications associated with high sodium concentrations in the body, especially for white-browed penguin chicks. To counteract this, white-browed penguins, as well as many other marine bird species, have a highly developed salt gland located above their eyes that takes the high concentration of sodium within the body and produces a highly saline-concentrated solution that drips out of the body from the tip of the beak. White-browed penguins do not store as much fat as some of its relatives; white-browed penguins require less energy investment when hunting because the net gain of energy after hunting is greater in white-browed penguins. As embryos, white-browed penguins require a lot of energy to develop. Oxygen consumption is high for a developing white-browed penguin embryo. As the embryo grows and requires more oxygen, consumption increases exponentially until the white-browed penguin chick hatches. By then, the chick is consuming around 1800 ml O2 per day.

The breeding colonies of white-browed penguins are located on ice-free surfaces. Colonies can be located directly on the shoreline or considerably inland. They prefer shallow coastal areas and often nest between tufts of grass. In their southernmost range, for example, breeding colonies are 2 km inland. In colonies farther inland, where the white-browed penguins nest in grassy areas, they shift location slightly every year because the grass becomes trampled over time. White-browed penguins breed monogamously and infidelity is typically punished with banishment from the colony. Nests are usually made from a roughly circular pile of stones and can be quite large, 20 centimeters (7.9 inches) high and 25 centimeters (9.8 inches) in diameter. The stones are jealously guarded, and their ownership can be the subject of noisy disputes and physical attacks between individuals. They are also prized by the females, even to the point that a male penguin can obtain the favors of a female by offering her a choice stone. Two eggs are laid, both weighing around 130 grams (4.6 oz). The parents share incubation, changing duty daily. The eggs hatch after 34 to 36 days. The chicks remain in the nests for around 30 days before joining other chicks in the colony and forming crèches. The chicks molt into subadult plumage and go out to sea at around 80 to 100 days.

The white-browed penguin is listed on CITES Appendix I, which means that all international commercial trade in white-browed penguins or their body parts is prohibited. It is listed as Least Concern on the IUCN Red List since 1980, as the white-browed penguin is not currently thought to be threatened and have thrived in areas near Lieran people settlements. However, captive breeding programs may be beneficial for the species' survival.