Benthic Biodiversity of seamounts in the southwest Indian Ocean

Lead Research Organisation: Scottish Association For Marine Science
Department Name: Contracts Office

Abstract

Benthic biodiversity of seamounts in the southwest Indian Ocean Seamounts are centres of biological diversity and are ecological hotspots in the deep ocean but their inaccessibility poses major challenges for research. In consequence, there are conspicuous sampling gaps of which the equatorial regions and most of the Indian Ocean are the most extensive. The southwest Indian Ridge (SWIR) is a major geological feature which extends from the central Indian Ocean to join the Mid-Atlantic Ridge in the Southern Ocean. It is rich in seamounts and supports a productive deep-water fishery yet, in terms of biodiversity and ecosystem functioning, it is one of the least sampled regions of the global ocean. We propose to study the diversity and distribution of benthic assemblages, from meiofauna to megafauna, on seamounts in the central section of the SWIR between 41 degrees S 42 degrees E and 33 degrees S 58 degrees E. The benthos of this region is completely unstudied and is of particular interest in terms of its position in relation to major ocean currents, gradients of primary productivity, and recent predictions as to the global distribution of cold-water corals. The region may be regarded as the most significant gap in our understanding of the seamount fauna globally. By studying the associations between faunal assemblages and habitat types, the genetic relatedness of populations, and the relationships between surface productivity, currents, and benthic distributions, we will enhance understanding of the processes governing the distribution, abundance, diversity and evolution of fauna on oceanic seamounts. A new habitat-suitability model based on environmental niche factor analysis (ENFA) has predicted that hard substrata in the southern Indian Ocean, down to ca. 2,500 m, are prime habitats for cold-water scleractinian corals. We propose to test these predictions by comparing the distributions and abundances of coral species across the study area with modelled distributions. Confirmation of the model predictions would lend support to recent concerns that increases in anthropogenic carbon dioxide emissions are likely to cause range shifts in calcareous marine organisms. A recent initiative from the deep-sea fishing industry working with the United Nations Food and Agriculture Organisation (FAO) has proposed a number of voluntary benthic protected areas (BPAs) on the SWIR in which no bottom trawling will take place: three of these are within the proposed study area. This is an unprecedented event in international waters and presents a unique opportunity to study the effectiveness of BPAs in protecting deep-sea habitats and species in the high seas. Detailed information on fishing effort at the study sites, available through industry collaboration, will allow us to assess the effects of trawling on slow-growing deep-sea benthic assemblages, and to gather baseline information against which the process of recovery following cessation of fisheries can be assessed.

Publications

10 25 50
 
Title Deep-sea Collection - 
Description A local designer with a keen interest in marine science has developed a deep-sea collection using images of the specimens that were collected on the expedition. The images have been printed on to silk scarves and were exhibited at a small fashion show. The full launch will take place in Autumn 2019 
Type Of Art Artistic/Creative Exhibition 
Year Produced 2019 
Impact The scarves with the deep-sea animals on them were showcased at a small fashion show at the Satchi Gallery in London. The products will be fully launched in Autumn 2019 
URL https://www.crubag.co.uk/
 
Description The diversity of the smaller sized fauna (>0.25mm - ~2cm) was much higher than expected.
The biodiversity varies across the different seamounts, but at present does not appear to be directly correlated to productivity. Instead biodiversity may be linked to habitat heterogeneity - the more habitat types there are the more species we are finding. The habitat type also appears to influence the type of fauna that we are seeing with striking differences in the composition at phyla level (i.e. more polychaete worms in some habitats, whilst in others crustaceans dominate).
We have also found that there is a hidden diversity of fauna living inside coral/carbonate skeletons which was somewhat unexpected. The older, and therefore "softer" the coral/carbonate the more fauna found living inside. This also appears not to be related to the productivity gradient across the seamounts.
Potentially many new species have been found and we have been using molecular techniques to clarify this.
Exploitation Route Final results may be used by other:
Scientists studying seamount ecology, genetics, connectivity, impact of fishing, litter to name but a few.
Those working on policy and law - the seamounts studied here are in an area outside of any country's National Jurisdiction, i.e. they are on the High Seas. All the seamounts may be considered in the future as Ecologically and Biologically Significant Areas (EBSA's), two have already started the process and have been accepted for the next round of discussion.
These seamounts are also in an area where countries are interested in mineral exploitation and licences have already been granted in the region.
Many scientists, policy makers, environmental lawyers will undoubtedly work together in the future in order to try and ensure that the fragile habitats found on the seamounts are not completely destroyed.
Sectors Education,Environment,Culture, Heritage, Museums and Collections,Other

 
Description we are looking to see how the findings may be used in a wider context
First Year Of Impact 2015
Sector Education,Environment
Impact Types Societal

 
Description MASTS Deep-Sea Forum smalll grant scheme
Amount £993 (GBP)
Organisation Marine Alliance for Science and Technology for Scotland 
Sector Public
Country United Kingdom
Start 12/2014 
End 11/2015
 
Description MASTS smalll grant scheme
Amount £500 (GBP)
Funding ID MASTS SG41 
Organisation Marine Alliance for Science and Technology for Scotland 
Sector Public
Country United Kingdom
Start 07/2012 
End 11/2012
 
Description SAMS Small grant scheme
Amount £1,981 (GBP)
Organisation Scottish Association For Marine Science 
Sector Charity/Non Profit
Country United Kingdom
Start 01/2013 
End 03/2013
 
Description British Science Festival - Newcastle 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? Yes
Geographic Reach International
Primary Audience Public/other audiences
Results and Impact Arts/education outreach event

Greater interest by children in science
Year(s) Of Engagement Activity 2013
 
Description Deep Sea Halloween - Careers Fair 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Schools
Results and Impact To raise awareness and interest of the deep-sea to school children - especially those choosing subjects that will influecne their future univeristy degree choice.

Greater interest
Year(s) Of Engagement Activity 2013
 
Description Deep Sea Halloween Open Day 
Form Of Engagement Activity Participation in an open day or visit at my research institution
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Public/other audiences
Results and Impact Almost 100 people attended raising interest and awareness of the deep-sea.

The realisation that litter can be found a long way into the oceans
Year(s) Of Engagement Activity 2013
 
Description Deep-Sea Halloween Nursery Visit 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Schools
Results and Impact To raise interest in nursery aged children (3-5) about the deep-sea, the animals found living there.
A slide show was followed by looking at animals from the deep as well as making their own animals.

Nursery children wanting to see a real ROV and thinking it "cool that Mum's could be scientists and work with underwater robots!"
Year(s) Of Engagement Activity 2011,2013
 
Description Deep-Sea Halloween Schools Visit 
Form Of Engagement Activity Participation in an open day or visit at my research institution
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Schools
Results and Impact ~50 pupils attended a halloween event aimed at stimulating interest in the deep-sea and the animals found living on seamounts.
Science and arts were combined to make it more memorable

More visits by children to the OEC centre at SAMS
Year(s) Of Engagement Activity 2013
 
Description INDEEP - ONC meeting (Vancouver Island) 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? Yes
Geographic Reach International
Primary Audience Other academic audiences (collaborators, peers etc.)
Results and Impact Interest raised in the issues of sampling on a seamounts

Colleagues from other Institutes expressed interest in visiting SAMS to work out future projects & collaborations
Year(s) Of Engagement Activity 2014
URL http://www.oceannetworks.ca/science/getting-involved/workshops/onc-indeep-partnership-development-wo...
 
Description Mountains of the deep - High Schools visit 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Schools
Results and Impact Presentation given to High School students

Some students showed greater interest in science and the deep sea
Year(s) Of Engagement Activity 2012
 
Description NERC - Planet Earth 
Form Of Engagement Activity A magazine, newsletter or online publication
Part Of Official Scheme? Yes
Geographic Reach International
Primary Audience Other academic audiences (collaborators, peers etc.)
Results and Impact The article was a mixture of deep-water biodiversity reasearch undertaken by B Narayanaswamy

Raised awareness in NERC/SISB about issues regarding marine biodiversity research within the UK
Year(s) Of Engagement Activity 2013
 
Description Open Day 
Form Of Engagement Activity Participation in an open day or visit at my research institution
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Public/other audiences
Results and Impact Lab open day

Greater interest and requests for more visits
Year(s) Of Engagement Activity 2012
 
Description Open Day 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Public/other audiences
Results and Impact Event took place at the Oban Highland Games

Raised lots of awareness of the deep-sea
Year(s) Of Engagement Activity 2012
 
Description SAMS Seminar Series 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Other academic audiences (collaborators, peers etc.)
Results and Impact Seminar on:
Discoveries made along the Southwest Indian Ocean Ridge: including new results investigating the microbial community structure and ecology
Bhavani E Narayanaswamy, Anni Djhuruus and Natalia Serpetiit

Potentially greater collaboration between SAMS & Oxford
Year(s) Of Engagement Activity 2013
 
Description Schools visit 
Form Of Engagement Activity Participation in an open day or visit at my research institution
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Schools
Results and Impact Raise interest and awareness of underwater mountains in the deep sea
Combined slide show, physical specimens and arts & craft

greater awareness adn interest and wanting to come back to OEC
Year(s) Of Engagement Activity 2014