The method by which Vampire Squid detect prey and evade predators is very complex and highly specialized. First, to detect prey Vampire Squid hang motionless in the water column, with its velar filaments hanging down below. When a prey (such as copepods, prawns and cnidarians) bumps into the velar filaments in the dark or when attracted to light produced by photophores, the stimuli is transmitted up the filament and the Vampire Squid responds by rapidly swinging itself around and envelops its prey using its webbed arms.
When approached by a predator, the Vampire Squid goes to great lengths to confuse it. It begins by taking the “pineapple pose” – it inverts its webbing and arms, surrounding most of its head and mantle. The black colouring of the webbing is more difficult to see and the cirri appear sharp and formidable. The Vampire Squid then opens the photophores near its fins, creating the impression of two great glowing eyes. It then shrinks the size of these photophores to give the impression of retreating. Additionally, the photophores on the arm tips light up and are waved in a fashion that makes it appear to be coming closer to the predator. Generally the predator is too confused on the position of its prey to attack. If this display fails, and the predator approaches further, it ejects the glowing particles from its arm tips and makes a rapid escape.
The "pineapple pose" - the webbing and arms have been inverted, exposing the cirri.
The bright points on this image are the arm tip and fin base photophores, lit up in response to the presence of a dangerous predator (the camera).
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