Lionfish Hunting Techniques Count on Confusion

Red Lionfish (Pterois volitans)
Red Lionfish (Pterois volitans), photographed on the Great Barrier Reef off Australia.

INVASIVE LIONFISH HAVE BEEN A PROBLEM FOR NATIVE FISH SPECIES throughout  the Atlantic/Caribbean since their introduction into Florida waters in the 1980s. For one thing, they have the advantage of preying on fishes unaccustomed to their modus operandi. For another, lionfish hunting techniques are fast, crafty and sneaky.

In the Indo/Pacific basin, they’re formidable predators anyway, equipped with a wealth of venomous spines, superb camouflage in colorings and body shape and an ability to herd and corner prey, sometimes working in teams.

ANOTHER LIONFISH HUNTING TECHNIQUE: CONFUSION

Turns out they’re sneaky little devils as well, according to a study, which found that P. volitans often utilizes a technique of blowing jets of water toward their prey to confuse or distract them and cause them to turn to face the predator – and present an easier target.

In the Gulf of Mexico, the crew of the liveaboard MV Fling collect lionfishes to send to researchers at Texas A&M.

PREDATORY MOVES   

While bony fishes have long been known to have the ability to produce pulses of water, this behavior by lionfishes appears to be the first time it’s ever been observed in use to capture other fishes as prey, researchers at SUNY at Stony Brook found in a study published in the journal Marine Ecology Progress Series.

They observed the behavior in lionfishes in both aquaria and open ocean waters in the Bahamas, noting it in 100 percent of aquarium feeding trials and 23.2 percent of field observations of actively hunting lionfishes. Smaller lionfishes appear to use the technique more often than larger ones.

Pacific denizens used the lionfish hunting technique more often than invasive lionfish in the Atlantic/Caribbean, the authors found, suggesting that the metabolic energy costs involved are more valuable for dealing with prey who have otherwise learned to evade or defend against lionfish predation.

DOUBLE EFFECTS

The use of water jets directed against prey fish may produce two results, they found. They may overwhelm the prey fishes’ lateral lines, masking detection of vibration signals associated with the predator’s strikes. And they may cause the prey to turn to face the predator, enabling an easier, faster head-first capture.

Source: Invasive red lionfish Pterois volitans blow directed jets of water at prey fish, Marine Ecology Progress Series.

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