Thank you for the question.
In the paper I mentioned, from 2010, I speculated that they have to have some kind of chemical within their tissues, because we know of a broad variety of other fish species, including some salmonids, that have a so-called alarm cue that is typically released from their skin when a pike, for example, comes and bites them. It's like a chemical warning signal to the other conspecifics—individuals of the same species—that it has been attacked and to watch out and go away.
We figure that sea lamprey must have something similar. In fact, Dr. Michael Wagner, who works at Michigan State University and is a permanent scientist for the Great Lakes Fishery Commission, has shown that they have shown avoidance behaviour toward decaying sea lamprey extract.
I'll be working with freshly killed sea lamprey as well as juvenile sea lamprey tissue extract. Basically, I'll take a certain amount of tissue, grind it up, dissolve it in water, release it in water, and see what they do. There is very positive science that shows that they avoid it. Of course, it doesn't kill them. It's not a control method; it's a behavioural manipulation method.
I'll give you an example of how it works. Imagine that the width of this room is a stream, and on one corner you have a dam—