The greatest number of accidents occurs during the summer months, when maritime traffic, in particular of ferries and private boats, reaches its peak.
As whales are not detectable by radar, chances to detect their presence is rather low. For this reason, at least during the day, it is important to have at least one observer scanning for cetaceans on the track line, to inform and alert the Captain and prevent hurting the animal.
In addition to the risk of collisions, the intense maritime traffic is responsible for problems including pollution, noise and habitat degradation.
In the Mediterranean Sea the two species of cetaceans most threatened by collisions with speed boats, cargos and ferries are the largest ones: the fin whale (up to 24 m in length) and the sperm whale (up to 18 m).
These animals, like all cetaceans, come to the surface to breathe and may remain at the surface for long periods of time. This behavior, coupled with the large size which slows their reaction time and movements, is among the causes that make these two species more vulnerable to collisions.