Biogeographical patterns in the deep ocean: environmental, biological, and historical drivers in the North Atlantic

• Main Author: Ramiro Sánchez, Berta
• Other Authors: Henry, Lea-Anne, John Roberts, Telmo Morato
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: The University of Edinburgh 2021
• Subjects: deep-sea; corals; management; North Atlantic
• Online Access: https://hdl.handle.net/1842/38153; https://doi.org/10.7488/era/1420

In the last century, our perception of deep{sea environments has changed from being biological deserts to nding thriving and complex habitats teeming with biodiversity. Some deep{sea habitats, such as cold-water coral reefs, coral gardens and sponge grounds, are often inhabited by slow{growth, long{lived, late{maturing species; traits that limit their potential for resilience and recovery from human pressures such as bottom{contact shing, climate change and, potentially in the future, deep{sea mining. These vulnerable species and habitats are recognised as in need of protective management and conservation measures, given their critical role in the functioning and services of the ocean and planet. However, most of the deep seabed lies in areas beyond national jurisdiction, where little is known about species distributions and where governance is limited. To date, biogeographic patterns in the deep{sea have been based on the distribution of model soft{bottom taxa that potentially may show di erent biogeographies to habitat{forming species as a reflection of their unique evolutionary history and environmental adaptations. Thus, an improved understanding of biogeography of complex deep{sea habitats such those formed by cold{water corals and sponges is an essential step to achieve conservation targets and the adequate implementation of management initiatives. In this thesis, I focus on the North Atlantic to study the biogeography of vulnerable species and habitats to help inform regional management. The lack of an agreed classi cation for the deep sea hinders the implementation of biodiversity targets through a network of Marine Protected Areas. Because of the lack of biogeographic data in the deep{sea, the existing marine classi cations Global Open Oceans and Deep Seabed (GOODS) and the Ecological Marine Units (EMUs), which are purely based on physiognomic proxies implemented with expert knowledge and statistical modelling, respectively, have been promoted. Nevertheless, one caveat in the use of GOODS and EMUs is ...