Tag: cold water corals

Science, What's New

How do marine heat waves affect cold-water corals in the deep-sea?

Ocean temperature plays an important role in governing the biophysical environment and in turn the realized ecological niche of benthic organisms and the distribution of marine habitats in the global ocean. As a result of anthropogenic-induced climate change Marine Heat Waves (MHWs) have resulted in widespread coral bleaching and mass mortality of tropical corals. Comparatively little is known about the impact of sub-surface MHWs on cold-water coral communities in the deep-sea, which lack the dependence on symbiotic zooxanthellae of their tropical cousins in surface waters. This study aims to address this deep-ocean knowledge gap utilising numerical modelling.  

Previous studies have shown that prolonged and intense sub-surface MHWs and their cumulative intensity results in increasing thermal stress encountered by benthic organisms in depths down to 2000m. This study utilises hydrodynamic modelling outputs of reanalysis data to study impacts of sub-surface MHWs on cold-water corals. With intensification and duration of sub-surface MHWs predicted to rapidly increase in this century, it will increase the thermal stress experienced by cold-water corals and associated communities in the deep-sea.

It is hypothesized that through increased stratification and increased mixed layer depth due to increased storminess and deepening of the thermocline, cold-water coral distribution will be impacted physically (mechanically), however their mortality is more likely to be dependent on food availability and oxygen supply. Preliminary results support this hypothesis in the North Atlantic, indicating that although the cold-water corals may be resilient to thermal stress physiologically, the resulting physically dynamic environment will lead to secondary impacts at the local scale in the benthic boundary layer. Furthermore, oxygen saturation has been found to decrease with increasing temperature and is likely to have a secondary impact on cold-water coral health. This study demonstrates how numerical modelling can provide quantitative spatial and temporal information of biophysical interactions to inform marine habitat mapping studies and species distribution models of habitat suitability. 

(Background: This is my research abstract made for the GeoHab 2024 conference – if you would like to learn more, my short oral presentation will be happening on Thursday 9th May 2024 at 1415 in Arendal, Norway. More information about the conference, including how to be a virtual participant, on the official conference website. An interesting program!) See also: https://www.marineheatwaves.org

New update: Marine Heat Waves Shiny App!!

seabed habitats seminar series

World Ocean Day Seminar on cold water corals

This Tuesday June 8th at 1300 BST for World Ocean Day, Dr Aaron Lim of Green Rebel Marine will be giving a seminar on “Mapping and monitoring cold water coral habitats offshore Ireland. The talk will introduce cold water corals habitats, how we map and image them, how we monitor them and some recent findings from offshore Ireland. We have wanted to organise an event about cold water corals for a while on this blog so this is particularly exciting for this year’s World Ocean Day! Don’t miss it- register below for occasional updates and zoom link.

Management

Happy Earth Day 2013

CIEarthDay

As part of Earth Day 2013, Monday 22nd April 2013, Conservation International’s (CI’s) Chairman and CEO Peter Seligmann took part in a Twitter conservation, where followers had the opportunity to send in their own pressing questions about conservation issues important to them! Representing seabed related issues, I decided to ask two questions about rhodoliths and deep sea habitats.

The question on rhodoliths was referring to a recent discovery of the world’s largest rhodolith beds off the coast of Brazil- which cover an estimated 21 000 square km area- an area nearly the size of El Salvador! (Original news article here, with blog post here.)

Rhodolith beds off eastern Brazil
Rhodolith beds off eastern Brazil (© Rodrigo L. de Moura)

Another user asked about the which areas CI will be focusing their conservation efforts in future. A particularly interesting answer to the question was:

Reflecting on Peter’s answer, this coupling between research and education, industry and governments seems to me to be the key to responsible environmental management. Of course this is indeed difficult to do in practice. You can follow more about the organisation’s work on their website, with the full twitter conversation here

Science

Cruise aboard RV Thalassa: France – Iceland – Azores

The ICE-CTD research cruise investigated cold water coral reefs and seawater properties around coral and non-coral areas. The objective was to characterise the present and past coral environmental conditions. Coral were sampled for dating, geochemical and genetic studies. The GIS Technician’s job mainly involved using ArcGIS to prepare the ROV dive routes and produce maps. They were also in charge of transferring the real-time data and comparing the real-time routes with the planned dive.

The ship left Brest on the 11th of June and headed straight to the Icelandic waters. It was initially planned to investigate the Logachev mound province but this was cancelled due to bad weather conditions. The ROV was deployed in three locations off southern Iceland and coral reefs were found in each area. Included are pictures from some of the spectacular locations discovered. The ship docked in Reykjavík for one night, allowing everyone to scramble off and explore Iceland’s beautiful scenery (geysers, icesheets, the mid-atlantic ridge, waterfalls!). The ROV team left the ship at Iceland and the rest of the team continued down the middle of the Atlantic to the Azores. CTD measurements were taken along the way and ARGOS floats were deployed, but it was a much quieter cruise on the way back.

Here is the link to the cruise blog:

Image Credits

All the pictures are taken by the GENAVIR ROV team and are credited to the following source: ICE-CTD cruise on N/O Thalassa, conducted by the LSCE and IFREMER under the lead of Dr. Norbert Frank, Laboratory for Climate and Environmental Research LSCE. (links: http://www.lsce.ipsl.fr and http://www.ifremer.fr and contact email Norbert.Frank@lsce.ipsl.fr and Sophie.Arnaud@ifremer.fr) and to Fiona Stapleton, National University of Ireland, Galway.

Science

Interview with British Researcher Chris Yesson

The second in our series of interviews, Dr. Chris Yesson, Institute of Zoology,  Zoological Society of London speaks about habitat suitability modelling of cold water corals and his team’s work as part of the CoralFISH FP7 project. He discusses his work the to identify suitable habitats for octocorals and stony corals from the North Atlantic and globally.  Interview carried out at the Zoology and Marine Biology Museum, National University of Ireland, Galway. For more information please see the Institute of Zoology, Zoological Society of London website.

Acknowledgements

Special thanks go to Dr. Chris Yesson for permission for inclusion of this interview in this blog.

Science

Interview with Icelandic Ecologist Julian Burgos

Benthic ecologist Julian Burgos, Marine Research Institute, Iceland, gives us a rare perspective about cold water corals living in Icelandic deep waters and his team’s work as part of the CoralFISH FP7 project. CoralFISH is assessing the interaction between cold water corals, fish and fisheries, in order to develop monitoring and predictive modelling tools for ecosystem based management in the deep waters of Europe and beyond. More information about the findings of the study can be found on the CoralFISH website.

Acknowledgements

Special thanks go to Dr. Julian Burgos for permission for inclusion of this interview in this blog.