Let's think about this. Take the Pacific Ocean, for example. It has approximately 710,000,000 km3 of water in it. When converted into weight, the Pacific Ocean is about 1, 565, 255, 731.9 Pounds total. As a comparison, a large lion fish weighs 2 pounds. This means that 100 lion fish would only be 200 pounds. Because I do not have the density of a lion fish, I'm going to take the percentage of weight 100 lion fish make up in the Pacific Ocean. 200/1, 565, 255, 731.9 = 1.27774648e-7 x 100= [b].0000127%[/b]. This means that the weight of the ocean drastically outweighs the collective weights of the lionfish. Lion fish make up .0000127% of the ocean's weight. If translated into volume, the results would be similar if not less. Therefore, the chances of finding 100 lionfish in an ocean is astronomically low. [spoiler]this also means lion fish are critically endangered.[/spoiler] Thanks for your time, I hope you pick the proper answer. Even if the region is dense, it is not dense enough.