RTSea: What do lionfish and moon jellies have in common? In Florida, it's the goliath grouper. And what links these three sea creatures together is our ability to meddle with the balance of nature.I have written about lionfish, moon jellies, and groupers in the past (Click here for lionfish, here for jellies, and here for groupers). The lionfish is a beautiful and graceful addition to any South Pacific reef where it exists as a predator that keeps reef fish communities in balance. As an invasive species to Florida and the
Caribbean (possibly inadvertently introduced in the early 90's), the lionfish is a voracious predator with an enormous appetite and their numbers have exploded in recent years, posing a significant threat from Florida throughout the Bahamas to reef ecosystems unprepared for such a hungry eating machine.Sea jellies, or jellyfish, are also beautiful and graceful, but the yin to their yang is the powerful sting in the tentacles of many species, an ability that is used for hunting and feeding rather than as some sort of offensive or defensive weapon. In recent years, scientists have been seeing a greater number of sea jelly "blooms" - huge congregations that some believe are the result of warming temperatures due to climate change or, possibly, a lack of common predators like turtles, tuna, and sharks. For scientists, the jury is still out as to a definitive cause but the anecdotal observation is that sea 
jelly blooms are being reported with greater frequency.The goliath grouper, capable of reaching up to a massive 800 pounds, is one of Florida's apex predators, right up there with sharks, billfish, and the other denizens of the deep that nature has entrusted to maintain equilibrium between predators and prey. Unfortunately, the goliath grouper was also a prized catch for sportfishermen and commercial operators and so their numbers declined rapidly over the past few decades. Listed as critically endangered in Florida waters by the International Union for the Conservation of Nature (IUCN), in 1990 Florida imposed restrictions on the taking of any goliath grouper. However, like sharks and other apex predators, the grouper's slow reproductive rate has meant a slow recovery and a typical large grouper is currently in the 200-pound range if you're lucky to see one. Read Full: A Tragedy of Errors: the fate of lionfish, moon jellies, and groupers are intertwined
