The coral reefs off Florida have become infested with another invasive species: lionfish. Originally from the Pacific Ocean and popular as aquarium fish, lionfish are colorful and sport venomous spiky tentacles. They're also voracious predators — posing a threat to the small fish that thrive around coral reefs. To control this marine pest, conservation groups are encouraging fishermen to catch lionfish and eat them. Groups are holding competitions — including a recent one in Key Largo — where hundreds of fish are being culled and eaten.