Cape Crozier is within a restricted area and permission is required to visit it. Cape Crozier is home to one of the largest Adelie penguin colonies in the world (~270,000 breeding pairs as of 2012),[9] of the two southernmost emperor penguin colonies (>1900 breeding pairs as of 2018),[10] and one of the largest south polar skua colonies in the world (~1,000 breeding pairs).[11] It also hosts several species of lichens, including at least three not previously found in this part of Antarctica.[12] It has been designated an Antarctic Specially Protected Area (ASPA 124),[13] and designated an Important Bird Area (IBA) by BirdLife International.[14] In 2001, the emperor penguins that lived in Cape Crozier were severely affected after an enormous iceberg known as Iceberg B-15 blocked off access to the sea for the birds.