The issue of collisions

The impact of collisions on cetaceans

Growing volumes of vessel traffic with evermore powerful and fast vessels will likely result in increased whale-vessel collision risk, a threat to cetacean’s persistence. More than 400.000 ship movements were registered and 1.200 vessel/cetaceans’ collisions have been recorded in the European Seas of which at least 50% in the Mediterranean Sea since 2009.

Vessel collisions with cetaceans currently account for up to 30% of known fatalities.

Globally, 14 areas of high-risk of collision between whales and vessels have been identified, including the Mediterranean Pelagos sanctuary having a collision rate which is 3.25 times higher than in the rest of the world.

Evidence demonstrate that collisions are an actual threat to cetacean populations, contributing to their decline.

Collisions with vessels and unidentified floating objects

There have been 13204 human casualties reported by the European Maritime Safety Agency between 2014 and 2019. Among these, 13% were due to collisions.

496 fatalities were reported within the same period and 55% of them were due to a collision (30%) and/or flooding/foundering (25%).

The SeaDetect project targets the problem of collisions at sea in the Pelagos sanctuary

Pelagos Sanctuary

The Pelagos Sanctuary for Mediterranean Marine Mammals is a marine protected area located in the north-western Mediterranean Sea between France, the Principality of Monaco and Italy, that provides critical habitats for several threatened species of dolphins and whales regularly inhabiting the Basin.

Recent studies show that collisions with vessels are one of the main causes of mortality of large whales in the Sanctuary area with 27 to 40 fin whales affected every year. With an estimated annual growth of vessel traffic between 3.5-4.0% the risk of collision will double in the next 18-20 years in the Pelagos Sanctuary waters.

Source: Sanctuaire Pelagos

SeaDetect Targeted species

Source : Tethys

The two main targeted endangered cetaceans’ species in SeaDetect project are:

  • The sperm whale (Physeter macrocephalus) ;
  • The fin whales (Balaenoptera physalus)

which are priority species listed in the European Union Habitats Directive.

Existing mitigation solutions

In Pelagos, REPCET is the only existing system used. The REPCET system is a cooperative mitigation measure based on sharing real-time sightings of cetaceans. Its efficiency in reducing ship strike and near miss events increases as the number of vessels equipped with it rises. Few vessels were equipped with this system in 2021 (39 vessels). The REPCET system is based on manual entries made by a visual watch during the day.

Source : Tethys


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