The difference between a seahorse and its coveted prey, the copepod, is infinity.
Copepod, a type of crustacean, have a 2 to 3 millisecond getaway time from the moment they detect prey -- one of the fastest responses in the animal kingdom. Yet, seahorses move so quietly the crustacean is ingested before it can even react (click for video), according to a new study. Copepods really have no chance: seahorses hunt them with a 90 percent success rate while the typical fish succeeds only 30 to 40 percent of the time, according to a previous study.
New research studied how the unusual shape of a seahorse's head and the actions of its mouth contribute to its predatory prowess, National Geographic reported.
Copepods cannot see and rely on a keen sense of water disturbance to detect predators. Most fish aren't steady enough to penetrate that defense, though most fish don't have the unusual snout formation or the feeding preferences of a seahorse.
Because its snout is long and thin, a seahorse can move within range of a copepod without causing much water disturbance and remain undetected. Once it's close, the seahorse doesn't need to initiate contact. Rather, it gets about a millimeter away and "pipes" or vacuums the crustacean through its mouth.
The seahorse "creates this zone with very little disturbance, which allows them to get really close to these very sensitive, highly evasive copepods," said study author Brad Gemmel, a marine biologist at the University of Texas.
"Once the seahorse gets within range the story is pretty much written, as far as the fate of the copepod goes," added Gemmell. His research was published Tuesday in the journal Nature Communications.
As an unfair backup option, seahorses can strike with their mouths in less than a millisecond, according to the study.
Seahorses lose some of their advantage in rougher waters, where copepods have a more difficult time distinguishing predator from current and other fish have a much easier time catching them, according to the study.
