Just when you thought it was safe to go back in the Gulf of Mexico, a new menace, this one striped like a big cat, is preying on aquatic life: The black tiger shrimp.

The biggest saltwater shrimp in the world, black tigers “are cannibalistic as are other shrimp but it’s larger so it can consume the others,” Tony Reisinger, country extension agent for the Texas Sea Grant Extension Service, told CNN on Friday.

Because of the threat of disease, the predatory intruder poses a problem for the native shrimp and oyster population of the Gulf, Reisinger said.

"Our oystermen right now are hurting because the oyster season is shut down due to a red tide. But this (black tiger) shrimp poses other concerns,” he said.

Appearing more than 25 years ago, the black tiger’s sudden reappearance is a mystery.

“The first time they started appearing was in the late 1980s on the East Coast,” he said. “Then they disappeared in 1991.”

But following the record-breaking hurricane season of 2005, which brought successive monster storms Katrina, Rita and Wilma, they started showing up again, he said.

“They’re well over 1,000 of them in the Gulf of Mexico now,” he said. “We’ve had five of them caught off Texas.”

Reisinger said he spoke to the Brownsville-Port Isabel Shrimp Producers Association recently to warn them about the shrimp but he was too late.

“It turns our fishermen have been catching them for a while, but they didn’t think they were marketable so they were throwing them back,” he said.

Is there a harvestable population already established in the Gulf? What does that mean for the Louisiana and South Texas shrimp and oyster industry? Many questions remain, Reisinger said.