Stock Photo - An adult Leucistic Gentoo penguin Pygoscelis papua nesting and incubating two eggs at Gabriel Gonzales Videla Research Station, Antarctica Leucism is a condition characterized by reduced pigmentation in animals Unlike albinism, it is caused by a reduction in all types of skin pigment, not just melanin A further difference between albinism and leucism is in eye colour Due to the lack of melanin production in both the retinal pigmented epithelium RPE and iris, albinos typically have red eyes due to the underlying blood vessels showing through In contrast, leucistic animals have normally coloured eyes The Gentoo Penguin is one of three species in the genus Pygoscelis It is the third largest of all penguins worldwide, with adult Gentoos reach a height of 51 to 90 cm 20_36 in There are an estimated 80,000 breeding gentoo penguin pairs in the Antarctic peninsula area with a total population estimate of around 314,000 breeding pairs in all of Antarctica Males have a maximum weight of about 8 5 kg 18 8 lbs just before moulting, and a minimum weight of about 4 9 kg 10 8 lbs just before mating For females the maximum weight is 8 2 kg 18 lbs just before moulting, but their weight drops to as little as 4 5 kg 10 lbs when guarding the chicks in the nest Birds from the north are on average 700 g 1 5 lbs and 10 cm 4 in taller than southern birds They are the fastest underwater swimming penguins, reaching speeds of 36 km/h Gentoo Penguins are listed as Near Threatened on the IUCN Red List