Question:
In order for your mutant dragon population to become its own species, and needs to be separated from the original dragon population so they no longer will mate with each other. come up with an idea of how the mutant dragon population can separate itself from the original population. Link it to your environmental change.
Answer:
There are various tactics that can be used to separate the mutant dragon population, in order to create a new speices. One tactic is to lure the dragons to a location that provides them with a better food supply. Another tactic could be to temporarily relocate the whelps or fledglings, and leaving behind a trail for the Family to follow. The goal is separate the mutant dragon population from the other, and the propositions that I have provided above could possibly be the solution.
Note:
This is the best I could do with the limited information that was given. I advise that you only resort to this if truly needed. I don't have much experience or knowledge in this Topic. I just thought I might give it a try. I hope you get a better answer soon!