A young seven-metre long humpback whale was spotted several times near Saint-Malo in Brittany yesterday (February 9) after somehow navigating its way through the dam of a tidal power plant.
It was described by the local maritime authorities as an “exceptional event.”
"A cetacean, a one-year-old calf was spotted around 10:00 in the Rance, upstream from the tidal power plant," the maritime prefecture said.
It was later seen between Saint-Malo and Dinard in Ille-et-Vilaine and then again in Plouër-sur-Rance in the early afternoon, where walkers saw it "amongst the yacht moorings about 15 metres from the quayside".
The Gendarmerie Maritime has called for the public not to crowd the banks or go in search of the whale by boat.
Jean-Marie Loäec, director of the EDF tidal plant, which generates electricity, said the young whale had entered through the dam gates. "The turbines were stopped and the gates were open, so it must have got in through there," he told Ouest-France.
Professional divers were the first to spot the mammal on Thursday morning and sounded the alarm. The gates through which the calf whale entered are just wide enough to allow a mammal of this size to pass through. They open when the turbines stop.
"We were warned at the end of the morning by EDF and immediately put a boat in the water," said Valentin Danet, a marine biology engineer at the marine station (Cresco) in Dinard.
It went up the river to the Saint-Hubert bridge before returning to the tidal plant in the middle of the afternoon. Then it turned back towards Saint-Suliac, where it was observed in the early evening.
Sonar device being deployed to try to guide it back through sluice gates
The search was suspended during the night but was resumed first thing Friday morning. A sonar device was deployed on the water to try to redirect the animal towards the sea. Among the chartered boats enrolled in the search is the one belonging to the Al Lark association, marine environment and whale specialists.
"We will be monitoring the situation and we are hoping not to see it again. This will mean that it will have succeeded in escaping from the Rance," says Gaël Gautier, director of Al Lark.
To achieve this, the apparently healthy whale will have to pass through the sluice gates again. They are open at certain times of the day, including between 10:00 and 15:00, a wide enough opportunity to open a channel back to sea, they hope.
Humpback whales are occasionally spotted off the Breton coastline, and “even put on a show” in Ploumanac'h last winter but this is the first time that one has ventured into the Rance.
The humpback whale is the largest marine mammal after the blue whale and the fin whale. It can measure up to 14 metres and weigh more than 30 tonnes as an adult.
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