A new scientific field trial off the coast of Alicante, Spain, is evaluating an enhanced trawl technology designed to reduce the environmental impact of bottom trawl fisheries while maintaining commercial fishing performance.
The project is assessing the effectiveness of semi-pelagic trawl doors, also known as flying doors, against conventional trawl doors. Operating slightly above the seabed, the technology aims to reduce direct contact with the seafloor and minimise sediment disturbance, while maintaining the horizontal opening and stability needed for efficient fishing.
The initiative is a collaboration between the General Secretariat for Fisheries of Spain’s Ministry of Agriculture, Fisheries and Food, the General Fisheries Commission for the Mediterranean (GFCM) of the Food and Agriculture Organization of the United Nations (FAO) and the Spanish Institute of Oceanography, which is leading the field activities.
Although focused on commercial fisheries, a new field trial in the Mediterranean reflects the wider seafood sector’s efforts to reduce environmental impacts through innovation. Researchers are evaluating enhanced trawl technology designed to minimise seabed disturbance while maintaining the fishing performance required for commercial operations.
To ensure accurate comparisons, researchers are using a single commercial bottom trawl vessel throughout the trial. The vessel will first operate with semi-pelagic doors before switching to conventional doors on the same fishing grounds. Conducting both phases consecutively is intended to minimise seasonal, environmental and spatial variation.
The trial focuses on Mediterranean fisheries targeting commercially important species, including deep-water rose shrimp, European hake, red mullet, broadtail shortfin squid, blue and red shrimp, Atlantic horse mackerel, mantis shrimp and common pandora.
During the trial, researchers will assess catch rates, catch composition, gear geometry, trawl door behaviour and operational efficiency. According to Sergi Tudela, Fishery Officer and Coordinator of the GFCM Western Mediterranean Technical Unit, the objective is to determine whether semi-pelagic doors can reduce environmental impacts without compromising fishing performance or the practicality of day-to-day commercial operations.
The fisheries and oceanographic research vessel Emma Bardán will also map the seabed before and after trawling with both door types, providing a direct comparison of their environmental effects. In addition, it will monitor water clarity during fishing operations to measure the level of sediment disturbance caused by each trawl configuration.
The project forms part of the GFCM MedSea4Fish programme and supports implementation of the GFCM 2030 Strategy by generating scientific evidence on lower-impact fishing technologies. The findings are expected to help inform future fisheries management decisions aimed at balancing productive fisheries with the protection of marine ecosystems.
