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The work of the Tursiops Association since its foundation has contributed to the conservation and protection of cetaceans, other habitats, species and protected areas, as well as to promote the dissemination of research carried out on them, focusing especially on the Balearic Islands and the western Mediterranean.

The characterisation of marine mammals, the main objective of this initiative, directly complements the action of the project coordinated by the Biodiversity Foundation, LIFE INTEMARES , for the study of the seamounts of the Mallorca Channel to facilitate their inclusion in the Natura 2000 Network, while providing a more ecosystem vision by including the study of protected species in the work on habitats. On the other hand, according to the entity, the project is an important continuation of the “Study of correlation of the presence of cetaceans and underwater noise in the southwest of the Balearic Islands”, promoted by the General Directorate of Marine Environment of the Government of the Balearic Islands.

According to Tursiops, in the same way, in the long term the project contributes to society’s knowledge and appreciation of the ecosystems linked to seamounts, enclaves of special ecological interest that are still little studied due, above all, to the difficulty of working at great depths.

The general objective pursued by the project has been the characterisation of marine mammals in the seamounts of the Mallorca Channel to facilitate progress in completing the Natura 2000 Network.

The specific objectives were as follows:

• Carry out the characterisation and temporal description of the cetacean species present in the Ausiàs March area.
• To establish a comparative analysis of the presence of cetaceans in the area of Mount Emile Baudot, Mount Ses Olives and Mount Ausiàs March.
• To assess the correlation between the presence of cetaceans and environmental noise in the seamounts of the Mallorca Channel.
• Transfer the knowledge generated.

• Analysis of acoustic files to identify the presence of cetaceans in the Ausiàs March seamount. Two different types of sounds were analyzed: whistles (modulated sounds) and echolocation clicks (pulsed sounds).
• Statistical analysis of the data obtained, which allows an assessment of the occurrence rates and the temporal evolution of the different species on the Ausiàs March mountain.
• Comparative analysis of cetacean presence indices in the Ses Olives, Emile Baudot and Ausiàs March mountains.
• Analysis of underwater noise that allows an assessment of the occurrence index by species and months according to environmental noise.
• Determination of the optimal safe anchoring point of the passive acoustic device, agreeing on this point with the fishermen in the area.
• Programming of the passive acoustic device optimizing data collection.
• Anchoring of the passive acoustic device.
• Maintenance of the passive acoustic device, including changing batteries and replacing anchoring material, and downloading data from the device.
• Drafting of a results report and submission of this to the competent authorities.

In general, the actions carried out have served to meet the initial objective of the project of carrying out the characterisation of marine mammals in the seamounts of the Mallorca Channel to facilitate progress in completing the Natura 2000 Network. The development of this initiative has contributed to improving the necessary baseline information regarding underwater noise and the presence of marine mammals in these enclaves. The knowledge obtained serves as a scientific basis for the possible designation of the Mallorca Channel as a Site of Community Importance (SCI) of the Natura 2000 Network.

The data have been obtained through noise analysis in 10,172 recordings, representing 40,688 minutes of data spread over 5,086 hours with sampling, 56.66% of the total possible hours. Through whistle analysis, they analyzed and classified a total of 6,293 whistles according to the Hawaii Islands protocol, 2,429 according to the Northwest Atlantic and 9,603 according to the Temperate Pacific; having detected five of the six identified species: striped dolphin (Stenella coeruleoalba), common dolphin (Delphinus delphis), pilot whale (Globicephala griseus), bottlenose dolphin (Tursiops truncatus) and pilot whale (Globicephala melas). Through click analysis, it has also been possible to identify and quantify the presence of sperm whale (Physeter macrocephalus).