A groundbreaking underwater fish-sorting system has been tested on board research vessel Simon Stevin in collaboration with ILVOO Oostende, and innovation company Marelec is satisfied with the successful outcome of it AI Catch system.
This is the patented development project AI Catch, which includes an advanced underwater fish- sorting system for beam trawling. This system utilises advanced technologies to scan fish swimming in the net and then sort them underwater based on commercial value. It has the capability to release by-catch directly and alive, leading to a significant improvement in sustainability in the fishing sector.
The system includes a sonar scanner ring in the net and a gate that closes to redirect unwanted catch back to open water, ensuring the survival of non-target species. The AI Catch system is connected to the catching vessel via an electric cable and a specially controlled winch. The skipper can monitor the operation of the system in real time on a screen in the bridge.
The trials with ILVO were carried out at various depths up to 35 metres on the Westhinder and Middelkerke banks. A total of five tows were conducted over 36 hours.
According to Marelec, improvements have been made following these sea trials, and a second round of at-sea testing is anticipated.
‘The system could prove to be a milestone in efforts to reduce the by-catch of undersized fish and increase the sustainability of the fishing industry,’ a Marelec representative said.
‘With the growing need to minimise unwanted by-catch while ensuring sustainable fishing, Marelec sought an innovative solution to release by-catch directly and alive. One of the challenges in beam trawling is limited visibility underwater, making traditional camera systems ineffective. Marelec has overcome this challenge by using internally developed ultrasonic sonar sensors to detect fish in the net.’
Advanced imaging technology precisely determines the length of the fish, after which intelligent software decides whether the fish should be captured or directed to an escape route via a valve just before the cod end.
‘What makes this project even more remarkable is that Marelec developed all aspects internally, including sensors, mechanical valves, motors, electronics and software. This includes imaging, interpretation of sensor data, valve control, and real-time information provision for the skipper,’ the company’s representative said.
Marelec has previously demonstrated its ability to integrate electronics into fishing nets in a robust manner, thanks to previously developed marine and underwater systems.
