Warm summer leads to more reports of ‘biting fish’ in French seas
Grey triggerfish are present across French waters
More reports of ‘biting fish’ in France’s Mediterranean waters have been made this summer.
Incidents have been reported around Cannes (Alpes-Maritimes), and also nearby Juan-les-Pins in June.
Victims include a 94-year-old, who left the water at Bijou beach bleeding from her legs after being attacked several times by a fish and a 92-year-old was also bitten hard enough to draw blood.
Grey triggerfish bites
The bites are caused by grey triggerfish (Balistes capriscus, nicknamed poisson mordeur or biting fish in French) that are native to the Mediterranean as well as waters ranging from Canada down to Argentina and the west coast of Africa.
Grey triggerfish have a set of eight teeth in each jaw, and can bite hard enough to break mollusk shells, crustaceans, and sea urchins.
Their teeth are extremely sharp for their size (adults reach around 45cm in length and up to a maximum size of some 66cm), and grow continuously throughout the fish’s life.
Grey triggerfish can be seen gnawing at stones or other hard surfaces to grind their teeth down.
While it is rare for grey triggerfish to swim so close to the shoreline – they typically live in waters with a depth of up to 100 metres – the increasingly common reports of biting this summer point towards a change in habit.
Juvenile grey triggerfish are also more commonly spotted closer to the water’s surface and may be responsible for some biting.
The fish are territorial, and typically bite people / also other fish if they are too close to their nests.
This is not the only time triggerfish bite.
“It often bites to defend its territory, if you intrude upon the area it considers its own, but also to test whether what it encounters is edible,” said curator of the Banyuls-sur-Mer Biodiversarium Pascal Romans to media outlet Midi-Libre.
Presence reported as far north as the UK
When temperatures reach around 24C - 25C, grey triggerfish breeding season begins, increasing the inclination to defend territory.
In addition, the metabolic processes of grey triggerfish increase during periods of hot weather, making them seek food more often.
They are being reported as far north as the UK as temperature increases lead to milder water temperatures.
A map of where grey triggerfish populations have been reported is available on the Marine Life Information Network (MarLIN) website.
The map shows that the fish has been more regularly seen across the western coast of France, although typically in deeper water, as well as parts of the Normandy and Brittany coasts.
In the Mediterranean, clusters along the French Riviera (approximately Cannes to Monaco), east of Toulon, and around Montpellier have been reported.
It is unclear whether the increased presence of grey triggerfish across the Mediterranean is to be expected in future years, or whether the fish are just “a bit more visible during certain hot years,” said Mr Romans.
“In any case, this expansion has not been proven along the French Mediterranean coast.”
What to do if bitten
Note grey triggerfish are not the only animal in the Mediterranean that bite.
Other fish that bite include the oblade, the pataclet, and juvenile pompano. Jellyfish, weever fish, and stingrays are also present and can injure swimmers.
The tenacious nature of grey triggerfish means they will continue to attack, and not respond to attempts to be batted away.
You should therefore exit the water as soon as possible.
Once out of the water, disinfect the wound.
Bites are not poisonous, so you should not need to call emergency services except in the event of a serious bite causing a heavy loss of blood, etc.
If this is the case or if you have any concerning symptoms, call emergency services on 112 or 15, or look for lifeguards on the beach.
