The ocean is integral to our existence. For generations it has sustained our entire way of life, providing food and health benefits, and it remains an essential element of our economic and environmental survival.

However, the ocean is under threat. Climate change, increased development and other human activities are all having an impact on our coastal and offshore environments. If allowed to continue, the way of life we hold so dear will change irreparably.

There is a global consensus that action is required, and international organisations and governments – led by the United Nations – are driving that agenda forward. However, for local and global agencies to act, they need the sound science that can inform their policies and actions—and that is where a project like FISH INTEL comes in.

The €4.1million project, supported by €2.8million from the European Regional Development Fund via the Interreg France (Channel) England program, focuses on a series of sites along the coastlines of southern England, northern France and Belgium.

Black bream tagging off the Sussex coast (Image credit: Thomas Stamp)

FISH INTEL sees researchers from the three countries using a combination of fish tracking and underwater video surveys to understand more about fish movements and the habitats individual species prefer.

Their findings will be added to a growing amount of data assessing the impact of fishing, climate change and other human activities—including the ever-growing development of offshore renewable energy sites and offshore mariculture – on the Channel/Manche region.

Ultimately, it is hoped the research will enable stakeholders, enforcement bodies and policy makers across the region to implement Ecosystem Based Fisheries Management (EBFM) programmes. Through a whole-system approach, such programmes are designed to enhance conditions and water quality in these habitats, enabling activities to function in a sustainable way.

Speaking at the FISH INTEL project launch Dr Emma Sheehan, Associate Professor of Marine Ecology at the University of Plymouth and the project’s Principal Investigator, said: “There are increasing demands and stresses being placed on the marine environment. Over the coming years, the impact of factors such as human activity and climate change has the potential to grow exponentially. This is an exciting and far-reaching project and all the partners have a shared aim to protect the way of life in our coastal habitats and communities. But if we are to develop solutions which preserve our coasts, and the species that rely on them, we first need to understand which habitats we are trying to protect.”

A Focus on Key Sites and Key Species

The FISH INTEL project is centred around seven sites in southern England, northern France and Belgium that are home to a mix of small and large fishing communities.

With calls for fish consumption to increase in recent years, its aim is to provide a framework through which those communities can operate in a sustainable manner that enhances marine conservation, while preserving their livelihoods.

Since March 2021, researchers have worked with fishers along these coastlines to tag a range of important species with acoustic trackers. More than 100 receivers have also been installed so that individual fish can be monitored throughout the year to establish any movement trends.

At the same time, the research team is conducting habitat mapping exercises. Taken together, these two elements will establish if there are particular habitat characteristics sought out by certain species, painting a comprehensive picture of the type of sites that need to be protected in order for fish to continue to flourish.

Five species were chosen as the focus for the project because they are integral to both the economic and environmental health of the Channel/Manche region. They are:

• Atlantic bluefin tuna (Thunnus thynnus)
• European bass (Dicentrarchus labrax)
• Pollack (Pollachius pollachius)
• Crawfish (Palinurus elephas)
• Black bream (Spondyliosoma cantharus)

Findings From the First Year of FISH INTEL

Researchers from the University of Plymouth were already working to understand why bass populations were falling around the UK coastline.

After the new project launched in March 2021, a range of data generated by acoustic receivers from previous projects showed bass living around the UK’s largest offshore rope cultured mussel farm, operated by Offshore Shellfish Ltd, off the coast of Brixham, Devon. They also found tagged brown crab and lobster living in significant numbers under the farm.

In the summer of 2021, they then worked with the Isles of Scilly Inshore Fisheries and Conservation Authority (IoS IFCA) to deploy 12 acoustic receivers off the island of St Martins.

The Isles of Scilly, and sites off the coast of Brittany and Côtes-d'Armor in northern France, are some of the last strongholds for the crawfish, where they are also important for small scale coastal fisheries.

Crews prepare to deploy acoustic receivers off the island of St Martins (Image credit: University of Plymouth)

On the Islands, the team engaged with local commercial fishers and dive teams, tagging 36 individual crawfish and releasing them back into the water. Within days, one of the crawfish has already been spotted 200 metres from where it was released, giving an early indication of how these animals travel around and make use of their habitat.

Dr Thomas Stamp, Post Doctoral Research Associate at the University, said: “This exciting survey work was the first of a collaborative project to get a better understanding on how specific species, such as crawfish, use coastal seas. This endangered species provides a critical income to small scale fishing communities, and therefore we really need to understand where they go and what they’re doing before appropriate fisheries management policies can be developed.”

Meanwhile, researchers from the University of Exeter tagged 30 bluefin tuna in UK waters, with six receivers deployed along the southern coast of Cornwall.

The 7 centimetre tags send individually coded acoustic messages to listening stations moored on the seabed, allowing the team to record how long bluefin tuna are in UK waters each year. The tags will also help the project team understand when the fish arrive, and will provide the most comprehensive understanding of the importance of UK waters to bluefin tuna to date.

Dr Lucy Hawkes, Senior lecturer in ecology at the University of Exeter, said: “We typically see bluefin tuna in waters around the south-west UK in the summer and autumn months, but do not know if we are seeing the same fish every year, nor the same fish all summer. For the first time we will be able to tell, with the acoustic tracking tags sending data for up to five years.”

Pollack is increasingly popular in both the UK and EU, but they are thought to be a solitary species or exist as small dispersed shoals, in close association with habitats such as rocky reefs or shipwrecks. However, there remains very little knowledge on Pollack populations in the North Atlantic.

Researchers on the FISH INTEL project hope to address these evidence gaps by working with commercial and recreational fisheries across the Channel/Manche to tag and track over 100 fish in three sites.

Already in France, scientists from IFREMER, fisheries committees and the Université de Bretagne Occidentale have found a significant decrease of Pollack catches in the Iroise Sea and Bay of Saint Brieuc, which follows a trend seen in European bass, a species they are used to harvesting throughout the year.

According to fishers, this drop in catch is due to overfishing during the reproduction period and the rising number of recreational fishers, combined with insufficient or inadequate management rules. In Saint Brieuc and Bay of Seine, fishers perceived the use of Danish seine nets as being responsible for such decline.

Building on a Legacy of Sustainable Ocean Management

The practice of working with fishing communities to both sustainably catch and conserve important habitats is something scientists involved in the FISH INTEL project have been advocating for many years.

Since its designation in 2008, researchers from the University of Plymouth have been monitoring the effects of the Lyme Bay Marine Protected Area (MPA), implemented to protect around 200 square kilometers of the seabed from bottom towed fishing gear.

Scientists measure the condition of a crawfish before attaching a monitoring device and releasing it off the Isles of Scilly (Image credit: University of Plymouth)

That work has shown the number of different fish species inside the controlled zone is now more than four times greater than found outside the MPA’s boundaries, with 370% more fish to be found within the MPA than in similar areas outside it where bottom-towed fishing are still permitted.

Dr Emma Sheehan, who also leads the Lyme Bay Project, added: “Globally, the implementation of MPAs has increased rapidly over the last 25 years and they are part of several sites we are now studying through FISH INTEL. Through greater appreciation of how such measures can protect and preserve the ocean – among scientists, fishing community and other sectors – we can not only examine the benefits of such designations, but also suggest new areas where they can be introduced. In the face of the global climate and biodiversity crises, the need to do so has never been more pressing.”

The Partner Organisations Involved in the FISH INTEL Project are:

UK: University of Plymouth; University of Exeter; Centre for Environment, Fisheries and Aquaculture Science (CEFAS); Isles of Scilly Inshore Fisheries and Conservation Authority (IFCA); Marine Conservation Society.

France: Institut français de recherche pour l’exploitation de la mer (Ifremer); France Energies Marines; Université de Bretagne Occidentale; Comité départemental des Pêches et des élevages marins du Finistère; Ligue pour la Protection des Oiseaux/Sept Iles; Comité régional des pêches maritimes et des élevages marins de Normandie.

Belgium: Vlaams Instituut voor de Zee (VLIZ).

This feature appeared in Environment, Coastal & Offshore (ECO) Magazine's 2022 Summer edition, to read more access the magazine here.