Glass Sponges: Architects of the Antarctic seafloor
The productive areas of the Antarctic shelf are characterized by a unique benthic community, dominated by glass sponges (phylum Porifera, class Hexactinellida). Unlike most other large foundation species with carbonate skeletons (e.g. corals), hexactinellids feature skeletons made of amorphous hydrated silica – glass.These glass sponges thrive in the Si-rich Antarctic waters, reaching their highest densities here. Our research explores the intricate connections between cryo-pelagic production, its transformation near the seabed, and its incorporation into sponge biomass and Si spicules. We investigate the critical role of hexactinellid sponges in carbon and nutrient cycling on the Antarctic shelf through field and laboratory experiments, scientific diving, and remotely operated vehicle (ROV) studies.
Our research aims to understand the diet, feeding rates, and metabolism of glass sponges, while evaluating their impact on associated fauna. Through repeated surveys spanning decades, we track changes in benthic community, environmental and sedimentary DNA resulting from ice-shelf collapse, iceberg scour, and sea-ice variations. By studying these remarkable organisms in their environment, we seek to deepen our understanding of Antarctic benthic ecosystems and their dynamic responses to environmental changes.
Our research contributes to POF-IV Subtopics 4.2 / 6.1
