Researchers at work on the project off the Sussex coast

This project was led by Dr Valentina Scarponi, Lecturer in Ecology and Animal Biology in the School of Life Sciences, Professor of Conservation Ecology Mika Peck (Life Sciences) and PhD student Alice Clark (Life Sciences). Valentina and Alice told us about the research. 

Could you explain your project?

AC: We’ve been monitoring biodiversity along the Sussex coast since 2021. In that year, the Nearshore Trawling Byelaw was implemented by Sussex Inshore Fisheries and Conservation Authority (IFCA), covering 300 square kilometres of the Sussex coast.

The main aim of the Byelaw is to protect fish stocks so they recover from overfishing, and also to help promote the recovery of kelp beds, which, up until the late 1980s, dominated the Sussex coast.

As a destructive fishing practice, trawling is thought to be one of the drivers of ecosystem degradation, but there are a combination of factors affecting nature, including extreme weather events, pollution, sedimentation and rising sea water temperature as a result of climate change.

Where is the project based?

AC: Between Selsey Bill and Shoreham-by-Sea. This is the biggest part of the trawling exclusion zone. Some of our sites are inside and some outside the trawling zone, to allow us to compare the biodiversity in both areas.

What methods are you using?

AC: We’re using two main methods. The first is video surveys from technology called baited remote underwater video (BRUVs). We deploy the BRUVs – which are steel structures with Go-Pros attached to them – at each of our 28 sites for an hour and record biodiversity, then review the footage and identify the species.

We also use environmental DNA (eDNA), which is DNA that has been shed by different species in the water. We collect water samples in the same sites as where BRUVs are deployed. We then pass the water sample through a filter which catches any suspended DNA in our sample. The filters are sent off to a lab run by Naturemetrics, where the team extracts the DNA, sequence it, and then sends us a list of the species detected in each sample. We are able to compare the species in the eDNA with those we saw in the BRUVs and also compare the species detected year on year.

BRUVs allow us to collect data on the habitat, size and behaviours of fish, but eDNA is more sensitive and detects more species. Analysing the BRUVs data is also quicker, because we have groups of undergraduate and master students as well as international junior research assistants (iJRA) who are dedicated to identifying the species from the BRUV videos as part of their projects.

An SSRP grant funded the analysis of one of our eDNA samples in 2023. That has come back from the lab now so we can inspect it. Blue Marine Foundation, Sussex Wildlife trust and Naturemetrics are also involved with funding different aspects of the project.

What is the current status of the project?

VS: We went out to our sites in July to collect data for 2024. Every day we sampled three sites, leaving the BRUVs down for an hour at a time, and collecting eDNA samples at the same time.

We’ve just published our first paper, a baseline report from 2021 looking at vertebrate species detected by BRUVs and eDNA (Clark et al., 2024). We detected 81 species from our samples, including some endangered species like the Tope Shark and the European Eel. This paper received a lot of media attention, including ITV and BBC. It was a busy few days.

What is the potential of this research, in terms of public engagement or policy?

VS: Our data will document any changes in the ecosystem after a key conservation measure was put in place. Trawling is still allowed in the UK in most marine protected areas and so the Sussex trawling byelaw was one of a kind, and we hope others will follow. IFCA are already currently working on a new trawling byelaw in Beachy Head.

When the Byelaw was proposed, there was a lot of public support, generated partly by what was Help our Kelp and is now the Kelp Recovery Project, including a video narrated by Sir David Attenborough. Public consultations are key part of IFCA’s efforts to look after our coastlines.  

What is the overall ambition of your project?

VS: To keep monitoring and understanding what recovery looks like. We can observe what’s going on and share this information with the scientific community and the public. There are a lot of stressors on biodiversity including overfishing, climate change and pollution. We’re creating a new picture, but we don’t know what that picture will look like.

AC: We don’t necessarily expect the coast to go back to what it was in the 1980s, because so much has changed in the environment since then. However, removing a big stressor like trawling can only be beneficial for biodiversity and we are looking forward to seeing what these benefits look like.

How does this project make you feel?

VS: It’s really positive. It’s great to see changes being made and how passionate the public is about the ocean, especially when we often see a disconnect between humans and the amazing world that lives underneath the waves. Having the support of local communities is always key for conservation.

AC: People are excited to realise there are a lot of different species close to home that they weren’t aware of. It is still quite early days, we need to remind ourselves that it takes a long time for nature to recover. So far, the ecosystem appears fairly stable in terms of biodiversity, which is a positive in itself since Earth does find itself facing a biodiversity crisis. 

VS: We need to let nature do what it does, and give it a chance to recover - whatever that looks like - and keep working towards finding a balance between what humans need to survive and a long-term plan for nature recovery.

Read more about the project here. 

This project supports the fulfilment of the following two UN Sustainable Development Goals:

SDG 13 – Climate Action
SDG 14 – Life Below Water