Antarctica’s native land animals are all small invertebrates. They include mites, lice, springtails, midges and fleas, many of which are parasites of seals and birds. The largest animal that permanently dwells on land in Antarctica is a wingless midge that grows to just over 1cm long. Only a few bird species breed in Antarctica, among them are penguin specie, snow petrels, Antarctic petrels and South Polar skuas. Approximately 45 species of birds breed south of the Antarctic Convergence. Compared to Antarctica’s relative barrenness, the Southern Ocean teems with life. With krill as the basis of its food web, the Southern Ocean supports a wealth of fish, seal, whale and seabird species. Of greatest interest among Antarctica’s marine life are the marine mammals: whales and seals. While wildlife may not seem to be concerned about your presence you may in fact be causing it considerable stress. A single thoughtless gesture can cause the loss of an egg or chick to a predator, or the crushing of a seal pup by a frightened adult.