Fish Intel Network

An array of underwater receivers to track the movement of marine animals
Pollack
Keith Hiscock

Overview

The Fish Intel Network (FIN) is a series of underwater acoustic receivers used to track fishes, elasmobranchs and crustaceans. The network has revealed vital habitats for reproduction and feeding, and generated fascinating new insights into species behaviour, including site fidelity and impressive migrations. These novel insights are providing essential information to inform and evidence new ambitious sustainable ecosystem-based fisheries management and policy.
The network has grown substantially in recent years, and now over 180 active receivers are strategically positioned along the southern coast of England. These have been placed on shipwrecks and reefs, around rivers and estuaries, at offshore aquaculture sites and in Marine Protected Areas. Deliberately deployed in important areas for both commercial and recreational fishers, the network provides comprehensive coverage for tagged species of both conservation and commercial interest.
Regular servicing, in collaboration with local charter boats, is conducted to download data and maintain equipment functionality. We are continuing to deploy further receivers to broaden the network’s coverage.
 
 
Fish Intel Network
Fish Intel Network
Fish Intel Network
Fish Intel Network - lobster tagging
 
 

Connection with Europe (and the world)

Fish Intel Network receivers can detect animals that have been tagged by anyone using this technology. This allows us to build collaborations with global partners, creating a vital connection for tracking species that travel across international boundaries.
FIN is connected to receiver networks run by our partners in many European countries, and is part of the European Tracking Network (ETN). This allows receiver-network stewards to share their data with other scientists, and includes receivers that are deployed in a wide variety of habitats, including Offshore Wind sites.
Highlights of international collaborations include detections on the FIN network of endangered migratory species such as porbeagle sharks, twaite shad and European eels that have been tagged by collaborators in France, Belgium and the Netherlands.

There are many examples of our own tagged fish being detected outside the FIN Network, including black seabream crossing the English Channel into France and the Channel Islands, and European bass migrating into the Irish Sea and the North Sea.
Map showing the location of receivers in the Fish Intel Network and European Tracking Network:
Map showing Fish Intel Network receiver and collaborator receiver
 

History of the Fish Intel Network (FIN)

The University of Plymouth’s telemetry network started in 2018 through the I-BASS project funded by the European Maritime and Fisheries Fund (EMFF). The EMFF has also funded the project ROPE, which involved extending the network further including at the UK's first offshore mussel farm. The network was expanded in 2021 through the Interreg-funded FISH INTEL project, and in 2023 through three new Fisheries Industry Scientific Partnerships (FISP) projects, funded by Defra and led by the University of Plymouth. Through these projects, the Fish Intel Network is helping to support the sustainability of fishing in Europe.

Projects

Antique illustration of European seabass (Dicentrarchus labrax)
I-BASS (Immature Bass Acoustic Stock Surveillance)
Investigated how European bass use nursery areas in the southwest of England). The project was funded by the European Maritime and Fisheries Fund (EMFF).
ROPE
ROPE (Response Of predators to Protection and Enhancement)
Explored how commercially-important mobile species interact with an offshore longline mussel farm. Target species included brown crab and European seabass. The project was funded by the European Maritime and Fisheries Fund (EMFF).
FISH INTEL
FISH INTEL, funded by Interreg. This collaborative project with French and Belgium partners created the first multi-species, multi-country telemetry array in Europe.
It focused on seven pilot sites within the English Channel/la Manche and tracked economically-important fish species. Target species included crawfish, European bass, black seabream, pollack and bluefin tuna.
Pollack
Pollack FISP (Fisheries Industry Science Partnership)
Working with charter skippers from the recreational angling community to track the movements of the pollack around southwest England. The project is funded by Defra.
Angling for Sustainability
Angling for Sustainability
Works with local skippers and anglers to study recreationally-valuable black seabream and elasmobranchs (tope, starry smooth-hound, thornback ray and undulate ray). The project is funded by Defra’s Fisheries Industry Science Partnership scheme.
Fish Ropes
Ropes to Reefs
Working with the aquaculture industry to explore the environmental benefits of the UK’s first mussel farm. The project is funded by Defra’s Fisheries Industry Science Partnership scheme.

Findings and impact

Data from these projects are already providing some exciting results. For example, FISH INTEL generated insights into fish homing and roaming behaviour that have already been used to action important new management and policy decisions.
Our studies on the movement of crucial fisheries species such as European bass and black seabream are often used by regional conservation authorities to inform their decisions, including the management of Marine Protected Areas such as Marine Conservation Zones and bass nursery areas.
 

How does acoustic telemetry work?

The Fish Intel Network is using acoustic telemetry to track animals remotely, through acoustic tags and a network of receivers. A target species is caught and tagged with a small acoustic tag, either externally (usually for larger species such as rays or hard-bodied species such as lobsters) or internally. Tagging is all done under a Home Office license, with approval from the ethics committee at the University of Plymouth.
Each of these tags emits a unique series of sound pulses, known as the tag’s “acoustic ID”. When a tagged individual swims within range of an acoustic receiver, the unique acoustic ID is picked up. The receiver saves this with the date and time, so the animal’s location is recorded as a “detection”. Large receiver networks such as FIN allow us to gain an understanding of movement patterns of marine species by piecing together detections from receivers deployed over a wide area.
Fish Intel Network tagging

Studying fine-scale movements

Beyond simply telling us about where a species if found, receiver networks can also be designed to gather a more nuanced understanding of species’ behaviour and habitat use.
Receivers have a range of about 300m, depending on the conditions, and locating them close together can allow an animal to be detected by three or more receivers at once. The animal’s position within the array of receivers can then be triangulated to within a few metres. This provides a better understanding of how target species interact with marine habitat features such as rocky reefs or shipwrecks, and can give insights into their behaviour at nesting grounds. FIN has four such arrays deployed off the Dorset coast.
 

How FIN is operated in the English Channel

The Fish Intel Network is operated and maintained by University of Plymouth staff, in collaboration with local charter boats and fisheries authorities. The network is serviced regularly, with download trips for each receiver planned every six months.
To retrieve the individual receivers, an acoustic transponder is placed in the water and communicates with the receiver on the seabed to “release”. The top plate of the unit then detaches from the anchored bottom rope cannister and floats to the surface, unspooling the rope stored in the cannister.
The receiver, along with the attached floats, then comes to the surface and is retrieved, with the attached weights still on the seabed. These are then hauled to the surface by the boat’s hydraulics system. Once onboard, data is then downloaded from the receiver and cleaned of all biofouling. The system is then reset and redeployed.
Other receivers are deployed on permanent infrastructure such as navigation buoys in harbours.
Fish Intel Network
Fish Intel Network
Fish Intel Network
Fish Intel Network
Fish Intel Network
Fish Intel Network
Fish Intel Network
Fish Intel Network
Fish Intel Network

Get in touch

We encourage collaborations with new partners and want people to use our network. We hope to continue to maintain and expand this network and are actively seeking funding to allow us to do so. Please do get in contact with Dr Emma Sheehan if you can help.
For further information, please contact us at fishtracking@plymouth.ac.uk.