Seahorse Use Their Heads to Stalk Prey [Video]

Researchers have discovered the mystery behind the odd-shape of a seahorse's head.

According to the study conducted by researchers at University of Texas at Austin, the long snout is hydrodynamic, allowing the creature to stalk and kill prey.

At first glance, the seahorse might not look much of a predator. These tiny creatures moving at incredibly slow speeds look like they are making a terrible attempt of copying a horse. And what's worse is that their body shape makes it difficult for them to swim in stormy seas.

It turns out that the seahorses are masters of stealth. Their heads are hydrodynamic, meaning that they can move about in still waters without being noticed. Their sculpted heads allows them to sneak upon crustaceans, creatures that can respond to tiny movements within a fraction of a second.

The planktonic copepods, seahorses' favorite food, are very fast and can cover a distance 500 times the length of their body in a second, which is the rough equivalent of a human covering 10 football fields in a single leap, according to AFP.
The seahorse catches its food by a technique known as pivot feeding. It turns its head upwards and draws in prey through suction. Now, suction only works at very short distances. So, the seahorse must get really close to these super-fast critters to get a good shot. That's when the equine-shaped head comes in handy.

"Seahorses have the capability to overcome the sensory abilities of one of the most talented escape artists in the aquatic world - copepods. People often don't think of seahorses as amazing predators, but they really are," said Brad Gemmell, research associate at the University of Texas Marine Science Institute, according to a news release.

For the study, researchers used a 3D holographic video to see dwarf seahorses (Hippocampus zosterae) in action. The team found that the creatures were 84 percent successful in getting within striking range without being detected by its prey. Once the seahorses were in 1mm strike zone, they had 94 percent chances of catching its food.

The study is published in the journal Nature Communications.

The head of a seahorse was earlier investigated by Dr. Sam Van Wassenbergh of the University of Antwerp in Belgium and colleagues who found that the head helps the creature probe a larger area for food. This study included comparison between seahorses and their relatives- the pipefish's- hunting technique. The pipefish is long, thin and straight, quite like seahorses' ancestor. Check a video of this analysis, here.

Why study seahorses? Understanding seahorse heads could help design stealth devices that could probe waters without disturbing the environment.

Seahorse sizes range from 0.6 inches to 14 inches. They are one of the few creatures that are monogamous. And, they are the only creatures where the male bears the unborn young.