Red lionfish, the invasive Pacific Ocean species, hunts like a terminator. This predatory nature can cause the termination of an entire native population of a species, according to a new study by the Oregon State University.
The researchers said that most native predatory fish hunt in areas where prey is abundant because minimum energy is required to catch and eat other species. These native predators normally travel to other locations when the population of prey diminishes.
The red lionfish, however, remains in one area until it eats all the existing prey. The finding of the behavior was described as "alarming."
"Lionfish seem to be the ultimate invader," said Researcher Kurt Ingeman in a press release. "And it's now clear they will hunt successfully even when only a few fish are present. This behavior is unusual and alarming."
For the study, the researchers placed red lionfish along with fairy basslet - a common prey of lionfish - in simulated natural reefs of Bahamas.
They found that lionfish terminated the entire population of fairy basslet. The popular aquarium fish live in small local populations and are therefore most susceptible to local elimination.
The researchers said that when prey fish were present in lower numbers, the rate of mortality amid the presence of lionfish was four times higher than those caused by native predators like medium-sized groupers or trumpet fish.
"Reef fish usually hide in rocks and crevices for protection, and with high populations, there is a scramble for shelter," Ingeman said. "Native predators take advantage of this situation by mostly eating when and where prey are abundant. As prey population levels decline, it takes a lot more energy to catch fish, so the predators often move on to other areas."
