An Ocean Census Flagship Expedition
20 February – 26 March 2025
#SouthSandwichIslands
The closest human beings to the Research Vessel Falkor (too) during this expedition might be orbiting the Earth on the International Space Station. The South Sandwich Islands is one of the most remote island chains in the world. It is a volcanic archipelago created by the South American Plate subducting beneath the South Sandwich Plate. Situated between the Southern and Atlantic Oceans, these islands are part of a rich mosaic of tectonic forces that create geologic features such as hadal zone trenches, underwater volcanoes, and spreading centers. These features facilitate high levels of endemism, supporting species found nowhere else.
This Nippon Foundation-Nekton Ocean Census Flagship Expedition will be led by Dr. Michelle Taylor, president of the Deep-Sea Biology Society and Senior Lecturer at the University of Essex; her team will locate and describe new species. Dr. Jenny Gales will lead GoSouth, a collaboration between the University of Plymouth, GEOMAR, and the British Antarctic Survey; her team will survey volcanic flanks with ROV SuBastian to determine the impacts of volcanism and earthquake activity on marine ecosystems. The science teams will also seek out deep-sea volcanoes and venture into the 8000-meter-deep South Sandwich Trench, the most geographically isolated and coldest trench on Earth.
Data from this expedition will contribute to the Ocean Census mission to accelerate the discovery of ocean life while advancing understanding of geohazards in the region and throughout our global Ocean. Additionally, the team will be joined by Artist-at-Sea Rosa Tharrats, a visual artist and costume designer from Barcelona, Spain, whose work incorporates recycled fabrics to explore concepts like transformation, symbiosis, and patterns between nature and culture.
Ten percent — and counting
We’ve only discovered 10% of ocean life. The Ocean Census is the largest program in history dedicated to discovering life in our ocean. Launched in April 2023 by The Nippon Foundation and Nekton, and as an endorsed UN Ocean Decade Programme, the Ocean Census coordinates an international alliance of research institutes, scientists, governments, media, and organizations.
Schmidt Ocean Institute has been a part of the Ocean Census alliance since its launch in 2023. The endeavor builds on historic efforts, including the 1872-1876 Challenger Expeditions, considered by many to be the birth of modern deep-sea science, and the 2000-2010 Census of Marine Life.
The goal is to revolutionize new species discovery within the coming decade and inspire people around the globe to care for our planet’s life support system. Over the last few decades, advances in underwater technology have virtually transported us to places unsafe for humans to travel and beamed back images that reveal the deep Ocean is not barren and devoid of life as was once thought.
Little is known about the biogeography of the South Sandwich Islands. How are currents and seafloor features restricting or enriching where animals live and reproduce? Researchers are excited to explore a potential biogeographic border created where the Antarctic Circumpolar Current (ACC) intersects with the Atlantic. This current creates distinct temperature boundaries that shape biodiversity and species adaptations. By sampling on both sides of this boundary, the team will compare how environmental conditions influence the evolution of life in these extreme habitats.
The team will explore deep-sea areas, searching for new species, and experts anticipate encountering many organisms new to science. They will collect abundant footage and samples for future taxonomic workshops. Taxonomy provides a structured approach to classify the diversity of life on Earth. By sorting organisms into categories, including family, genus, and species, scientists build knowledge on how different organisms are related and how species have evolved. As biodiversity is being lost at an unprecedented rate due to human activities, accurate data about existing biodiversity is critical for informing policy and conservation. Additionally, polar environments, broadly, represent some of the most rapidly changing marine environments on the planet. Huge volumes of cold water are lost yearly, and this exploration will help establish a baseline for understanding change in the future.
Tectonic Forces
Geohazards is a broad term for geologic events like earthquakes, volcanic eruptions, and tsunamis that might have catastrophic consequences for the environment and human life. Geohazards are especially pronounced near tectonic plate boundaries.
Several islands in the South Sandwich Islands chain are volcanically active, as are many seamounts. Due to their remote location, they are some of the least understood volcanoes in the world. At least two submarine mountains in the arc are caldera volcanoes and may be capable of a blast similar to the 2022 Hunga Tonga-Hunga Ha’apai eruption.
The region is also prone to earthquakes. On 12 August 2021, two large earthquakes occurred in the region: a magnitude 7.5 followed by a magnitude 8.1. The tsunami generated by these earthquakes reached the Atlantic, Pacific, and Indian Ocean basins. There was no known loss of human life; however, the quakes challenged many tsunami warning systems. Scientists worldwide struggled to identify where the tsunamis originated because of the South Sandwich Islands’ remote location and sparse seismic and sea level sensors in the region. The earthquakes also likely triggered underwater landslides, which may have significantly impacted the marine ecosystem and the impact is not yet understood.
Gales and the team will examine eruption and earthquake activity with a focus on the potential for tsunami generation and future geohazard risks. They will rely on mapping data, photogrammetric imaging, and ROV imagery to study how the earthquake may have changed the underwater landscape and if underwater landslides contributed to tsunami propagation. They will also explore how volcanic substrate shapes regional animal communities across local scales and whether they have changed over time.
Team
