Do you know what a lamprey is?

They are primitive fish that look something like eels, and parasitic. The adults of some species, such as sea lampreys, suck the blood of other fish. They're a problem in the Great Lakes, where they've done a number on native whitefish populations.

Female lampreys are drawn to males by the bile acid they secrete. That bile acid works as a kind of love potion isn't the only interesting part though. The bile acid works long-range. When the males release their bile from their positions within their nests, it attracts females from quite a distance. Although scientists had suspected that there may be water-released pheromones that work over long distances, lamprey bile acid was the first instance of this to be discovered. This discovery could very well lead to a way to manage lamprey in the Great Lakes, where, as you mentioned, they've been a threat to other fish populations.