idw – Informationsdienst Wissenschaft
Nachrichten, Termine, Experten
Nachrichten, Termine, Experten
24 March.2025/Mindelo/Kiel. This weekend the M209 expedition ‘BASIS’ led by GEOMAR Helmholtz Centre for Ocean Research Kiel has started. An international team is investigating the largely unexplored deep seas off the Cape Verde islands with the research vessel METEOR. To this end, the sea floor at islands and underwater mountains, so-called seamounts, will be mapped and the biotic communities and food webs observed, documented and sampled - from the water column to the sea floor. The GEOMAR underwater robot ROV KIEL 6000, which can dive to depths of up to 6,000 metres, will also be used.
The coastal ocean off Cape Verde islands consists of more than 90 per cent deep sea (waters deeper than 200 metres) and is still largely unexplored. An international research team has now set off on the research vessel METEOR to investigate the biodiversity, foodwebs and interactions of animals in the water column (mesopelagic zone) and on the sea floor (benthic zone), as well as the region above the seafloor (benthopelagic zone). “The unique conditions of working off Santa Antao and other Cabo Verde islands is that we can work close to shore, benefitting from sheltered conditions and still work in deep sea habitats, which are typically hard to access in open ocean conditions,” explains expedition leader and marine biologist Dr Henk-Jan Hoving from GEOMAR Helmholtz Centre for Ocean Research Kiel. The expedition is part of a research series focused on deep-sea in-situ observations around the Macaronesian islands.
Cape Verdean scientists on board
Three scientists from Cabo Verde are also part of the expedition, each with a different research focus: Rui Freitas, a fish expert with an interest in coral reefs, and works at the Universidade Técnica do Atlantico (UTA) and Keider Neves, who works at Biosfera1 and is a specialist in crustaceans and hopes to describe new species from Cabo Verde. Also on board is Vanessa Lopes from Projecto Vito, who studies whales and seabirds during M209 and investigates scientific need assessment for small island developing states. “The M209 expedition will support data collection and learning about deep-sea biodiversity in various regions in Cabo Verde, some of which are under proposal for a marine protected area. In addition, the experience is supporting knowledge exchange and knowledge sharing with young Cabo Verdean biologists who hope to continue to study the deep sea in their own home,” says Vanessa Lopes, who is doing her PhD research at the University of Edinburgh.
Large parts of the Cape Verde archipelago still unmapped
An important objective of the cruise is to map the seabed around the islands and on underwater mountains. “In many regions of Cabo Verde, we still don't know how deep the seabed actually is, and what the seafloor morphology is,” says Mareike Keller of the GEOMAR Deep Sea Monitoring Group and deputy chief scientist on M209. This basic knowledge is important for marine traffic in Cabo Verde but will also be important for future campaigns that plan to deploy instruments on the seafloor. An example is the upcoming international observation campaign FUTURO (Future West African Marine Ecosystems) off the West African coast from 2028 to 2030.
Parallel to the M209 expedition, the research vessel OceanXplorer is also spending a few days off the Cape Verde islands. The stay is part of the 2.5-month ‘Around Africa Expedition’ with African scientists, a collaborative effort conducted by two global ocean exploration nonprofits – OceanX and the newly established OceanQuest. During their joint stay off the coast and at the underwater mountain Nola (Seamount Nola), the scientists on board the METEOR and the OceanXplorer will carry out joint measurements and be in direct contact. Such a joint scientific operation with a multitude of oceanographic tools is also envisioned for the FUTURO research campaign.
Fragile and elusive animals and their foodwebs
Deep below the surface in the middle of the water column lives a large diversity of organisms consisting of jellyfish, crustaceans, lantern fishes and cephalopods. This community is the food for many commercially exploited fishes such as tuna. However, it is largely unknown what they feed on. Some may consume dead material (marine snow) that sinks down from the overlying water column, others eat living prey. To investigate the foodweb, the researchers want to collect gelatinous plankton, e.g. jellyfish, to find out what role these transparent, sensitive organisms play in the food web. To collect and study fragile animals, they are using a combination of different methods. As gelatinous plankton is almost impossible to catch with nets and bring on board undamaged, the remotely operated underwater robot ROV KIEL 6000 will be used to capture deep-sea organisms. The captured animals will be photographed in the lab and samples will be used for foodweb studies. In addition, towed cameras with acoustic sensors will be used to study the distribution and biomass. Finally, water from different depths will be filtered to capture environmental DNA which animals leave behind. This genetic tool allows detection of animals that are avoiding the instruments.
Where two worlds collide: interactions between midwater animals and the seafloor
Another objective of the expedition M209 is to study the interaction between animals in water column and the seabed. “In some places around the islands and seamounts, two worlds potentially collide. We expect that marine organisms in the middle of the water column of 400-500 metres also occur in some regions close to the seabed,” says Hoving. Many organisms also perform vertical migration, where they migrate from deep to shallow at night to benefit from food in shallow waters. Henk-Jan Hoving: “Afterwards these organisms may interact with the seafloor during their downward migration, and hence become food for seafloor organisms. The steepness of the slops of the islands and underwater mountains may make these interactions particularly intense.”
Currently, only around 7.7 per cent of the total area of the oceans is under protection. Cabo Verde is known as a hotspot of ocean biodiversity. The aim of marine protected areas is to preserve natural habitats, sustainable management and biodiversity. With the collection of basic biological data, the expedition M209 aims to collect information requested by Cabo Verde scientists on board and their institutes, and contribute to the design and proposal of marine protected areas in Cabo Verde waters.
Background: Research on Cabo Verde
The Cape Verde islands, around 6000 kilometres off the coast of Senegal, offer a unique range of scientifically current and highly relevant research topics in which the ocean usually plays a decisive role. GEOMAR has been conducting research there for 20 years together with regional and international partners, and since 2017 it has been operating the Ocean Science Centre Mindelo (OSCM) together with the Instituto do Mar (IMar) in Mindelo, which is available to the international scientific community with its infrastructure. Another important component is the WASCAL programme for West African Master's students, which is supported by GEOMAR and has been established since 2019. WASCAL stands for West African Science Service Centre on Climate Change and Adapted Land Use. In addition to lectures and practical courses, the programme also includes a two-week, sea-based ‘Floating University’ training component, which is coordinated at GEOMAR.
Project funding:
The expedition is funded by the Federal Ministry of Education and Research (BMBF) and the German Research Foundation (DFG).
Expedition at a glance:
Name: METEOR-Expedition M209 „BASIS“ (Benthic and Pelagic Biodiversity, Ecology and Habitat Mapping in Cabo Verde Deep Seas)
Chief Scientist: Dr Henk-Jan T. Hoving
Duration: 21.03.2025 – 23.4.2025
Start: Mindelo, Cabo Verde
End: Ponta Delgada, Azores
Cruise Area: Tropical Atlantic
http://www.geomar.de/n9798 Images available for download
https://www.geomar.de/en/research/expeditions/detail-view/exp/377006?cHash=fe3db... METEOR M209
https://www.geomar.de/en/centre/research-in-cape-verde Research on Cabo Verde
https://futuro-campaign.org/ FUTURO campaign
https://oceanx.org/press-room/article/groundbreaking-launch-of-oceanx-and-oceanq...
Merkmale dieser Pressemitteilung:
Journalisten
Biologie, Geowissenschaften, Meer / Klima, Umwelt / Ökologie
überregional
Forschungsprojekte
Englisch
Sie können Suchbegriffe mit und, oder und / oder nicht verknüpfen, z. B. Philo nicht logie.
Verknüpfungen können Sie mit Klammern voneinander trennen, z. B. (Philo nicht logie) oder (Psycho und logie).
Zusammenhängende Worte werden als Wortgruppe gesucht, wenn Sie sie in Anführungsstriche setzen, z. B. „Bundesrepublik Deutschland“.
Die Erweiterte Suche können Sie auch nutzen, ohne Suchbegriffe einzugeben. Sie orientiert sich dann an den Kriterien, die Sie ausgewählt haben (z. B. nach dem Land oder dem Sachgebiet).
Haben Sie in einer Kategorie kein Kriterium ausgewählt, wird die gesamte Kategorie durchsucht (z.B. alle Sachgebiete oder alle Länder).
