In this clip from BBC’s Life, narrated by David Attenborough, a sarcastic fringehead must go to great lengths to protect its home.
The sarcastic fringehead (Neoclinus blanchardi) is a small saltwater tube-blenny found in the north-east Pacific Ocean, known for its massive jaw and mouth, and particularly bad temper. This fish will fight anything it deems a threat – even its own reflection.
Sarcastic fringeheads are long, slim and mostly scaleless. They can grow up to 30cm in length, but most range between 8 to 20cm. They don’t look all that impressive until they open their enormous mouth – which can become a whopping four times their size when open compared to closed. Inside, they have sharp, needle-like teeth.
Apart from their truly bizarre looks, one might wonder where the strange name comes from. ‘Fringehead’ is said to refer to the floppy, fringe-like fronds of tissue that fall over the fish’s eyes. ‘Sarcastic’ is thought to either describe the animal’s cynical closed-mouth expression, or to derive from the Greek word sarkázein, which means ‘to tear flesh’.
“These fish are exceptionally quarrelsome – they have to be to defend their living space,” narrates Attenborough.
The fringehead moves in short, rapid movements, not afraid to lunge at any intruder – an octopus, for example. Although the octopus can hold its ground and defend itself from the fringehead with its impressive jab, the small fish still makes it scurry away.
The next intruder is another fringehead – and this is where the conflict gets ugly. Male sarcastic fringeheads use their enormous mouths to assert dominance. They will come at each other with mouths agape, neither prepared to back down. Finally, a winner emerges, and the fringehead retreats into its shell. But the fight isn’t over.
“A fringehead can never drop its guard. There’s too much competition,” concludes Attenborough.
Top image credit: Brent Durand/Getty Images
