I've wondered about this myself. Without touching on Verboten subject matter, it does appear to me that the general trend may be heading towards warmer weather. If this occurs, what happens to the Tilapia laden ponds down south? It's often said that the winter die off is exactly what you want to happen, so what's the plan if it doesn't always work out that way?
Manual removal, or hope that the predator/prey ratio sustains itself accordingly?