In a deadly game of heads or tails venomous sea snakes in the Pacific and Indian Oceans deceive their predators into believing they have two heads, claims research published today in Marine Ecology.
The discovery, made by Dr Arne Redsted Rasmussen and Dr Johan Elmberg, showed that Yellow-lipped Sea Kraits (Laticauda colubrina) use skin markings and behaviour patterns to fool predators into thinking their tail is a second head, complete with lethal venom.
There are over 65 species of sea snakes in the tropical waters of the Southern Hemisphere, ranging from Africa to the Gulf of Panama. Most spend their entire lives in the sea, inhabiting shallow water and are active predators, feeding on small fish found around coral reefs. All sea snakes have extremely potent venom which is among the most toxic known in all snake species.
When hunting for food sea snakes probe crevices and coral formations, temporarily forcing them to drop their guard to threats from the surrounding waters and making them highly vulnerable to attack. However, the Yellow-lipped Sea Krait has been found to twist its tail so that the tip corresponds with the dorsal view of the head, which combined with deceptive colouring, gives the illusion of having two heads and two loads of deadly venom.
Apart from the Yellow-lipped Sea Krait the ecology of sea snakes has largely gone understudied, due mainly to their off-shore and nocturnal behaviour. Yet, despite the number of behavioural studies devoted to this species, the discovery of this false-head-behaviour is a hitherto overlooked anti-predator adaptation.
The discovery was made while senior author Arne Redsted Rasmussen was diving off the coast of the Bunaken Island in Indonesia. A large Krait was followed for thirty minutes, swimming between corals and crevices hunting for food. Rasmussen was momentarily distracted by a second snake, but when looking back he was surprised to see the "
|Contact: Ben Norman|