The quantity of litter or marine debris in the world's oceans has been steadily increasing over the years. This is to be expected, as human populations, industrialisation and sea-traffic, especially fishing, increase. The Southern Ocean is the most remote of seas and even here marine debris is making its mark.
Marine debris is composed mostly of plastic.
Estimating its distribution and abundance in the Southern Ocean by direct methods is not practical for a number of reasons. First, the Southern Ocean is vast and the surface concentration of debris is very low. For example, a large surface net was towed behind the RSV Aurora Australis for one hundred kilometres, but it caught only surface plankton and a small fragment of seaweed. About 10 years ago studies showed that both Macquarie and Heard Islands had accumulated debris on their beaches. These studies also indicated that the rubbish washed ashore on the two islands was different, and originated from different activities.