Three sperm whales have been spotted in Balearic waters, crossing the channel between Ibiza and Mallorca as they headed towards Italy. "The sperm whales - Physeter macrocephalus - are here in the Balearic Islands, yet we often overlook them, despite being the largest predator of individual prey on the planet with the largest brain that has ever existed," explained Txema Brotons, a doctor in biology and expert in cetaceans. Brotons, who is also the scientific director of the Associació Tursiops, shared these insights during a recent conference organised by the Club Ultima Hora-Valores 2023.
The last sighting of these sperm whales was near the Columbretes Islands, an archipelago close to the coast of Castellón. This region is known to have one of the highest concentrations of these marine creatures in the Mediterranean, according to the Ministry for Ecological Transition and Demographic Challenge. Other potential breeding and feeding areas for these whales include the coast of the Marinas, Tabarca Island, and the Channel between Ibiza and Mallorca.
Currently, the biological sex of the three whales is unknown. Brotons noted that males can reach lengths of 16 metres and weigh 41 tons, while females typically measure around 11 metres and weigh 14 tons. These whales, known for their deep-diving capabilities, play a crucial role in regulating squid populations in the Mediterranean. Sighting them is rare, as they only surface for about 10 minutes to breathe before diving back down to depths around 1,000 metres.
Given their deep-sea habitat, sounds are crucial for the movement of sperm whales. Consequently, several hydrophones have been placed at strategic points in the Ibiza and Mallorca Channel to acoustically monitor and protect these mammals. To reduce the risk of boat collisions, various population monitoring campaigns have been conducted.
The three sperm whales were observed moving towards Italian waters. This species is considered an endemic population, largely specific to the Mediterranean region. While males can travel to the Straits of Gibraltar and even the Atlantic Ocean, most of the population remains in the Mediterranean throughout their lives. According to Brotons, there are an estimated 2,500 in the Mediterranean, with the majority concentrated in its western area.