A mass animal stranding has puzzled authorities in the West African island nation of Cape Verde after more than 130 dolphins died on a local beach this week.
Patrol officers on Tuesday morning initially found 17 melon-headed whales, which are considered mid-sized dolphins, on the coast of Boa Vista, the island’s official tourism website said in a statement. Later that morning, a total of 164 dolphins of the same species were found stranded in the area.
Dozens of officials and volunteers tried then tried to return the mammals to the sea, but most of them washed backed up and ended up dying, according to the statement.
Atualização do encalhe em massa Nos dois dias posteriores ao encalhe massivo de 163 golfinhos na Boa Vista, técnicos de...
By Thursday, a local environmental conservation group called BIOS.CV said at least 136 dolphins had died, including calves, juveniles and adults. Many of them have already been buried with bulldozers while samples from 50 of them as well as four carcasses have been preserved for further analysis.
Veterinarian, experts and government officials are expected to travel to Boa Vista in the coming days to determine what caused the phenomenon, BIOS.CV said in a Facebook post on Thursday.
Melon-headed dolphins are social animals and are often found in groups of hundreds or thousands, according to the U.S. National Oceanic and Atmospheric Administration.
“They are known not to abandon their group members and this may be the reason that so many followed their companions onto the beach,” Boa Vista tourism officials said in a statement, which also suggests that pollution, interactions with fishing vessels and even oceanic noise may have led to the mass stranding.
“Loud noises cause them to flee areas that are important to their survival and has also been demonstrated to drive groups to stranding and ultimately death," the statement reads. "This is unfortunately not a unique event on Boa Vista, yet the cause of the strandings is still unknown.”