The “Dofins de Tramuntana” project, initiated in 2017, has the primary objective of promoting the conservation of the bottlenose dolphin (Tursiops truncatus) and protecting the marine ecosystems in the Cap de Creus area in northern Catalonia, one of the most productive marine areas in the western Mediterranean.
The initiative has focused on monitoring bottlenose dolphin populations and actively collaborating with fishermen to assess the interaction between dolphins and fishing, as well as to promote their involvement in the conservation of the species. In addition to direct conservation actions, the project seeks to raise public awareness about the natural, cultural, and landscape values of Cap de Creus, fostering greater protection of this valuable marine environment. It is noteworthy that the Creus Canyon is part of the Natura 2000 network under the designation LIC ESZZ16001, which protects the submarine canyon system of the Gulf of Lion.
The results obtained indicate that the presence of dolphins around trawling vessels and their feeding activities near them are common in the waters of northern Catalonia, where 85% of bottlenose dolphin sightings are associated with the presence of trawlers.
Determining the degree and type of interaction between dolphins and fishing in this region is essential to evaluate the risks these interactions pose to both dolphins and the fishing economy.
In order to obtain this knowledge, in 2022, SUBMON carried out the COSTtERA project with the collaboration of the Fundación Biodiversidad, of the Ministry for Ecological Transition and Demographic Challenge, through the Pleamar Programme, co-financed by the FEMP. This project aimed to study the behaviour of bottlenose dolphins during their interaction with the trawling nets of the vessels and to determine the degree and type of fishing interaction in the northern Catalonia area. In a pioneering advancement in the Mediterranean, underwater cameras were installed on bottom trawling nets to observe and evaluate the behaviour of dolphins underwater and determine the nature and risk of interactions between dolphins and trawlers. This innovative approach allowed for the development of the first protocol for studying dolphins’ underwater behaviour during their fishing interaction and for obtaining the first images of dolphins feeding and interacting with trawling nets in the Mediterranean.
Subsequently, this work was continued through COSTtERA-2, where these efforts were further enhanced through the integration of new technologies, including state-of-the-art underwater cameras, drones to study surface behaviour, hydrophones for the analysis of acoustic patterns, and the development of artificial intelligence algorithms for the automated analysis of video and acoustic data.
These innovations enabled a more efficient data collection process and improved the understanding of the species’ behaviour in the context of its interaction with fishing activities.
In 2026, the COSTtERA-3 project was launched to consolidate and expand the knowledge generated in previous phases. The project further investigates the species’ distribution, behaviour, and the evolution of its degree of dependence on fishing activity. It also introduces new lines of work, such as body condition analysis and the development of predictive models to assess population responses under different fishing effort scenarios and environmental conditions, anticipating potential impacts linked to changes in resource availability.
All of this is supported by the use of innovative tools, including drones, underwater cameras, acoustic sensors, and artificial intelligence. The project strengthens the active involvement of the fishing sector and lays the groundwork for adaptive management based on scientific evidence.
