The Department of Environmental Affairs’ SA Agulhas II has embarked on her third logistical and scientific voyage to Marion Island on Thursday 9 April 2015.
During this voyage, scientists from the DEA’s Oceans and Coasts Research unit as well as from various universities in South Africa will jointly continue to monitor oceanographic processes – both physical and chemical changes in planktic and benthic communities. As well as population estimates and assessments of feeding and breeding behaviours of top predators in the Southern Ocean and at the Prince Edward Islands, where marine and terrestrial biological communities have shown responses to climate change.
These responses are evident in an increase in the spreading of terrestrial invasive species, including invertebrate and vascular plant species. In addition, warming of surface waters have been associated with a possible regime shift in zooplankton communities because of the increasing presence of subtropical species and a concomitant decline in Antarctic species over the past 30 years.
Moreover, an observed southward movement of the sub-Antarctic Front and associated changes in oceanographic conditions have been linked to a decrease in the frequency and intensity of the “island mass effect” resulting in less productivity in the waters around the islands. This is supported by a decrease in chlorophyll concentration near the islands since the 1970s, which in effect is probable cause of recent declines in populations of some inshore feeding seabirds off Marion Island, South African Govt wrote on the website.
Despite ongoing research and monitoring efforts, the Southern Ocean is still regarded as a comparatively data-poor area and it is therefore important that South Africa, being a party member to the Antarctic Treaty and CCAMLR, carries out its responsibility over its territory and surrounding high seas within the Southern Ocean.
Surveys need to be repeated to characterize changes in diversity and community structure of marine, benthic and terrestrial communities to assess changes possibly associated with the recent climatic shifts, including the presence of invasive species. These surveys also serve as a scientific reference point to monitor further changes and inform the future management of the area, which is one of the objectives of the recently declared Prince Edward Islands Marine Protected Area (PEI MPA).
The Director of Southern Oceans and Antarctic Support, Nishendra Devanunthan delivered the farewell speech on behalf of Deputy Director-General of Oceans Coasts, Dr Monde Mayekiso.
“One of the most serious threats to the conservation of the Island has been the introduction of alien species, in the form of plants and invertebrates. The Department is making every effort to avoid introducing new species to the Antarctic and sub-Antarctic, and it requires the cooperation of all participants in order to succeed. As a result the department will be sending a specialist from the Environmental Programmes branch who will focus on the Alien Eradication Programme (AEP) to evaluate ways and means to restore the island to its pristine state,” said Devanunthan.