I have seen pictures of sad polar bears that have less and less environment to live in. The Antarctica is more protected from significant warming and loss of living space, but are penguins nonetheless in danger?
There are altogether 18 species of penguins in the southern hemisphere. According to BirdLife International, currently 13 of them are red listed and thus have unfavourable population status. Ten species are listed as threatened mainly due to declining population trends. Climate change is a threat for most of the species and several studies have shown that either reproduction or survival of full-grown birds are related to climatic factors such as sea surface temperature. Climate change is warming the sea temperature, which has already caused changes in marine food webs leading to abundance changes of fishes and invertebrates, such as krill. Climate change impacts on penguins will likely manifest through these changes in food webs.
Penguins use large sea areas for foraging and actually most of the penguin species breed outside Antarctic ice areas on islands in the southern hemisphere around South America, South Africa, Australia and New Zeeland. Especially species, such as Galapagos, Yellow-eyed and Erect-crested Penguin, which have rather small distribution areas, e.g. breeding only in a couple of islands, are in danger. This is because they can not easily follow the changing climatic conditions. Moving of their breeding areas from one island to another is challenging since amount of islands is limited and suitable breeding locations can be situated very far away. For instance African Penguins have hardly any options to move southwards from South Africa. Studies have shown that penguin populations breeding in the Antarctica are also responding to shifting climatic conditions. For instance in King Penguins, populations which are situation on the southern edge of their distribution have increased whereas northern populations have declined. Overall, this means that populations are moving towards poles, which is a similar pattern that has been documented in many northern hemisphere animal populations including Finnish birds. According to species distribution modelling, population of the most cold-tolerant penguin species, Emperor Penguin, is expected to decline 20–29% within next 60 years. The local population of the Emperor Island already disappeared in 2009 (150 pairs in 1970s) due to changes in ice conditions.
In addition to climate change fisheries and invasive mammal species are currently serious threats for penguin populations.