CDTS305: “Ocean Sediments” Quantifying the interaction of anthropogenic impacts and hydrodynamics on Ocean Sediment habitats to inform ecosystem-based management of an understudied habitat

   The School of Biological and Marine Sciences

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  Dr Emma Sheehan, Dr Marija Sciberras  No more applications being accepted  Competition Funded PhD Project (Students Worldwide)

About the Project

Ocean sediments provide essential habitats for species of both conservation and commercial importance, however, due to their perceived mobile nature are often considered to be appropriate for all kinds of destructive human activities, such as dredging and trawling. Such activities may reduce the habitat quality and could compromise the retention of carbon. Due to shifting baselines associated with the historical extent of demersal trawling around the British Isles it is almost impossible to know what sediment habitats are like in the absence of human impact. In the Isles of Scilly, there is an opportunity to assess the impact of new trawling activity on relatively pristine ocean sediment habitat. This PhD will assess the impacts and recovery timescales of this habitat and associated ecosystem services in the Isles of Scilly and around the UK to inform and advise new ambitious ecosystem-based fisheries and conservation management. The interaction between ecosystem service provision, hydrodynamics and climatic variables such as extreme storms and marine heatwaves will also be explored.


Quantify the impact of bottom-towed fishing on ocean sediment habitats and the potential for recovering ocean sediments to form structurally complex habitats under different hydrodynamic settings, human levels of disturbance, and climate change related drivers. 


  1. Collate existing ecological data and Ocean Sediment habitat classification schemes. 
  2. Comprehensive assessment on the impact and subsequent recovery of bottom-towed fishing on pristine Ocean Sediments habitats, species and ecosystem services in the Isles of Scilly. 
  3. Analyse long-term ecological and oceanographic datasets to assess sediment habitat recovery potential. 
  4. Assess current and future threats (fishing, offshore renewables) and management solutions to optimise ecosystem services for the UK’s Ocean Sediment habitats. 


The candidate will be trained in semi-structured interviews, BRUV, ROV, and oceanographic surveys. The candidate will have access to state-of-the-art facilities and technical support at the University of Plymouth and will receive training in a variety of geostatistical models in the R statistical suite to model species multivariate data with oceanographic variables. Crucially, the candidate will learn on placements with Marine Conservation Society and Natural England’s senior marine advisors about translating socio-ecological and oceanographic data into impactful management and policy. 

Project structure 

The candidate will be based at the University of Plymouth within a lively marine research focused environment with direct access to research vessels, laboratories and field-survey equipment. The city is centrally placed in the south-west with easy access to a number of fishing ports across Dorset, Devon and Cornwall. The PhD data collection activities will be split between working at sea off fishing boats, and travelling to meet stakeholders around the south-west. 

The project will be supervised by Dr Emma Sheehan Associate Professor of Marine Ecology (UoP, lead supervisor), Dr Marija Sciberras Associate Professor of Marine Sciences (Heriot Watt University), Dr Tim Scott Associate Professor of Oceanography (UoP); Dr Sian Rees Associate Professor of Social Sciences (UoP), Dr Bryce Stewart Associate Professor of Fisheries Science (UoP/MBA) and an advisory group including fisheries experts, NGOs, government, and regulators. 


Applicants should have a first or upper second-class honours degree in an appropriate subject and either a relevant masters qualification or a wider range of experience in a relevant career path (which is equally as important).

Each applicant may apply for a studentship on up to three CDT SuMMeR projects. Where more than one project is applied for, the supervisors of all those projects will be made aware that other applications have been made.

The studentship is supported for 3 years and 8 months. All UKRI-funded PhD students (UK, EU, International) will be eligible for the full award – both the stipend to support living costs (£18,622 per academic year at full time equivalent at the 2023/24 rate), and fees at the research organisation’s UK rate. International students are eligible for UKRI-funded postgraduate studentships but UKRI will limit the proportion of international students appointed each year through individual doctoral training programmes to 30% of the intake per cohort. CDT SuMMeR’s funding will not cover international fees set by universities; applicants normally required to pay international fees may have to cover the difference between the home and the international tuition fee rates (approximately £12,697 per annum). Please enquire with the lead supervisor on the situation regarding international fees for the project you are interested in. CDT SuMMeR’s funding will not cover costs associated with visa application or health surcharges, or additional costs associated with entry to, and living in, the UK. For EU and international eligibility for UKRI studentships, see UKRI’s guidance.

In case of uncertainty, applicants should contact the planned university of registration for eligibility advice, or the CDT SuMMeR Programme Office: [Email Address Removed]

Anthropology (2) Biological Sciences (4) Environmental Sciences (13) Geography (17)

Funding Notes

CDT SuMMeR studentships are partially funded by the Natural Environment Research Council (NERC), which applies the eligibility criteria laid down by its parent body, UK Research and Innovation (UKRI), and co-funded by the respective Hosting Partner institutes. UKRI provides details on its training grants in its Terms and Conditions for Training Funding document, including its Training Grant Guide, which can be found on the UKRI website.