In the framework of the development of an anti-collision system, I am currently looking for information and scientific papers on fin whale (Balaenoptera physalus) and sperm whale (Physeter catodon) behaviour. This would help us to anticipate the displacement of these animals and to graphically represent their potential area of presence over a short period of time (for how long an individual is likely to stay in the same area …). Any information on time budgets (time spent feeding, resting, breeding, diving, socializing, etc.) and on the associated displacements (direction, speed, geographical area of presence, etc.) of these animals (fin and sperm whales) would be most appreciated. For instance, the following questions would eventually help us to estimate how long animals would stay on a feeding zone: • What is usually the utilized geographical area of sperm whales while feeding (the entire canyon or only a portion of it?)? • What is usually the size of North-western Mediterranean schools of krill? It would also be interesting to know the influence of seasonal variations as well as time of the day on these animals behaviour. Although this study concerns Mediterranean cetaceans, behaviour studies (on both species) carried out worldwide would be appreciated. Thank you very much for your time and consideration Best regards Delphine Gambaiani