Report of the Belgica 121 expedition to the West Antarctic Peninsula

There is a dearth of knowledge about biological and habitat diversity levels found in shallow areas from the Southern Ocean, a situation opposite to that found in other oceans. These ecosystems are exposed to fast-paced changes in key environmental parameters (seawater temperature, salinity, primary production, sea-ice regimes, ice-shelf loss/collapse) and host organisms which have been facing past events shaping the function and structure of ecosystems. The RECTO/vERSO projects funded by the Belgian Science Policy Office (BELSPO) have identified plasticities (trophic, dispersive) and connectivities as key areas of research to understand the response of Antarctic ecosystems to environmental changes. The Belgica 121 (B121) expedition aims at exploring the surroundings of the Gerlache Strait (Western Antarctic Peninsula) and to carry out a biodiversity census focusing on intertidal and shallow areas using both classic descriptive marine ecology methods as well as state-of- the art techniques (habitat mapping, genetics, trophic ecology). The expedition also bears a strong historic link to the first scientific expedition to overwinter in Antarctica in 1897-99 recording the first intertidal biodiversity data 121 years ago. This historic expedition was led by Adrien de Gerlache onboard the Belgica.

The present report gives a detailed account of the preliminary results of the B121 expedition.