Valentin Lauret, Hélène Labach, Léa David, Matthieu Authier, Olivier Gimenez

In the Mediterranean Sea, interactions between marine species and human activities are prevalent. The coastal distribution of bottlenose dolphins (Tursiops truncatus) and the predation pressure they put on fishing stocks lead to regular interactions with fisheries. Multispecies occupancy models allow mapping co-occurrence between two (or more) species while accounting for false negatives and potential interspecific dependance. Here, we illustrated how to extend multispecies occupancy model to integrate multiple datasets to quantify spatial co-occurrence between trawlers and bottlenose dolphins in the Gulf of Lion, French Mediterranean Sea. We combined bottlenose dolphin and trawler detections and non-detections from both aerial surveys and boat surveys in the Gulf of Lion and map potential interactions. Possibility to integrate several datasources into multipsecies occupancy models opens promising avenues in the study of interactions between human activities and marine mammals that occur at large spatial scales