Cold-water corals off New Zealand

The waters around New Zealand are considered a hotspot for cold-water corals. Cold-water corals are also counted as the architects of the deep sea, as they form large structures on the seabed with their coral mounds. Main skeleton builders such as Goniocorella dumosa, Madrepora oculata and Solenosmilia variabilis characterize these sensitive habitats. Despite their importance, the occurrences have hardly been researched to date. The CoralNewZ expedition, led by Prof. Dr. André Freiwald from “Senckenberg am Meer”, combines state-of-the-art technologies – including multibeam echosounders, ROVs and molecular genetic methods – to study the coral habitats in detail and understand their interactions with environmental factors. Together with the MARUM – Center for Marine Environmental Sciences at the University of Bremen and the NIWA (National Institute of Water and Atmospheric Research) from New Zealand, the team on board the SONNE is pursuing the goal of recording the diversity and functionality of these ecosystems and analyzing the long-term influences of climate changes.

Also on board is the remotely operated vehicle MARUM-SQUID, which dives into the deep-sea ecosystems. Weather permitting, the dives can be followed live on the internet (via marumTV on YouTube).

During the month-long expedition on the research vessel SONNE, the researchers will map and analyze current coral habitats and reconstruct the past of these ecosystems using sediment cores and fossil corals in order to understand the behavior of these ecosystems under different climatic conditions. The expedition is therefore an important step towards understanding how environmental changes - especially climate fluctuations - have affected the vitality of cold-water corals in the Southwest Pacific and could continue to do so in the future.