It is true that they resemble each other. Something else they have in common: their habitat is threatened by climate change. And yet, auks and penguins are two very different species. Any tips to help distinguish them? Penguins live in the Southern hemisphere, whilst auks enjoy the white expanses of the Northern hemisphere. And while they both have wings, the former cannot fly and uses them only for swimming. In terms of size, auks are around 50 cm tall and weigh 700 g. Penguins vary in height and weight: emperor penguins are 130 cm tall and weigh 40 kg whereas pygmy penguins are 40 cm tall and weigh 1.3 kg.